Integrated circuit device, circuit and method of operating a circuit
阅读说明:本技术 集成电路器件、电路和操作电路的方法 (Integrated circuit device, circuit and method of operating a circuit ) 是由 吴旻信 张盟昇 周绍禹 杨耀仁 于 2019-08-29 设计创作,主要内容包括:IC器件包括:反熔丝器件,包括位于第一栅极结构和有源区之间的介电层;第一晶体管,包括位于有源区上面的第二栅极结构;以及第二晶体管,包括位于有源区上面的第三栅极结构。第一栅极结构位于第二栅极结构和第三栅极结构之间。本发明的实施例还涉及电路和操作电路的方法。(The IC device includes: an anti-fuse device including a dielectric layer between the first gate structure and the active region; a first transistor including a second gate structure located over an active region; and a second transistor including a third gate structure located over the active region. The first gate structure is located between the second gate structure and the third gate structure. Embodiments of the invention also relate to a circuit and a method of operating a circuit.)
1. An Integrated Circuit (IC) device, comprising:
an anti-fuse device including a dielectric layer between the first gate structure and the active region;
a first transistor including a second gate structure located over the active region; and
a second transistor comprising a third gate structure located over the active region,
wherein the first gate structure is located between the second gate structure and the third gate structure.
2. The integrated circuit device of claim 1, wherein
The active region includes first to fourth source-drain (S/D) structures,
the second gate structure is located over the first and second source-drain structures,
the first gate structure is located over the second and third source-drain structures, an
The third gate structure is located over the third source-drain structure and the fourth source-drain structure.
3. The integrated circuit device of claim 1, further comprising
A first contact structure configured to electrically connect the active region to a conductor; and
a second contact structure configured to electrically connect the active region to the conductor,
wherein the first gate structure, the second gate structure, and the third gate structure are located between the first contact structure and the second contact structure.
4. The integrated circuit device of claim 1, further comprising:
a first via structure configured to electrically connect the second gate structure to a conductor; and
a second via structure configured to electrically connect the third gate structure to the conductor.
5. The integrated circuit device of claim 1, wherein the integrated circuit device is configured to conduct current from the first gate structure to a bit line through the first transistor and the second transistor in parallel.
6. The integrated circuit device of claim 1, wherein
The antifuse device is a first antifuse device,
the dielectric layer is a first dielectric layer, and
the integrated circuit device further includes:
a second antifuse device comprising a second dielectric layer between the fourth gate structure and the active region;
a third transistor comprising a fifth gate structure located over the active region; and
a fourth transistor comprising a sixth gate structure located over the active region,
wherein the fourth gate structure is located between the fifth gate structure and the sixth gate structure.
7. The integrated circuit device of claim 6, wherein
The active region includes first to seventh source-drain (S/D) structures,
the second gate structure is located over the first and second source-drain structures,
the first gate structure is located over the second and third source-drain structures,
the third gate structure is located over the third source-drain structure and the fourth source-drain structure,
the fifth gate structure is located over the fourth and fifth source-drain structures,
the fourth gate structure is located over the fifth and sixth source-drain structures, an
The sixth gate structure is located over the sixth source-drain structure and the seventh source-drain structure.
8. The integrated circuit device of claim 6, further comprising:
a first contact structure configured to electrically connect the active region to a conductor;
a second contact structure configured to electrically connect the active region to the conductor; and
a third contact structure configured to electrically connect the active region to the conductor, wherein
The first gate structure, the second gate structure, and the third gate structure are located between the first contact structure and the second contact structure, and
the fourth, fifth, and sixth gate structures are located between the second and third contact structures.
9. A circuit, comprising:
a wire;
a bit line;
an anti-fuse device;
a first transistor; and
a second transistor for controlling the output voltage of the transistor,
wherein
The antifuse device and the first transistor are coupled in series between the conductive line and the bit line, an
The antifuse device and the second transistor are coupled in series between the conductive line and the bit line.
10. A method of operating a circuit, the method comprising:
receiving a voltage at a gate of an antifuse device; and
the antifuse device is coupled to a bit line using both a first transistor and a second transistor.
Technical Field
Embodiments of the invention relate to integrated circuit devices, circuits, and methods of operating circuits.
Background
Integrated Circuits (ICs) sometimes include one-time programmable ("OTP") memory elements to provide non-volatile memory ("NVM") in which data is not lost when the IC is powered down. One type of NVM includes antifuse bits integrated into an IC through the use of layers of dielectric material (oxide, etc.) connected to other circuit elements. To program the antifuse bit, a programming electric field is applied across the layer of dielectric material to sustainably alter (e.g., breakdown) the dielectric material, thereby reducing the resistance of the layer of dielectric material. Typically, to determine the state of the antifuse bit, a read voltage is applied across the layer of dielectric material and the resultant current is read.
Disclosure of Invention
Embodiments of the invention relate to an Integrated Circuit (IC) device, comprising: an anti-fuse device including a dielectric layer between the first gate structure and the active region; a first transistor including a second gate structure located over the active region; and a second transistor including a third gate structure located over the active region, wherein the first gate structure is located between the second gate structure and the third gate structure.
Another embodiment of the invention is directed to a circuit comprising: a wire; a bit line; an anti-fuse device; a first transistor; and a second transistor, wherein the antifuse device and the first transistor are coupled in series between the conductive line and the bit line, and the antifuse device and the second transistor are coupled in series between the conductive line and the bit line.
Another embodiment of the invention is directed to a method of operating a circuit, the method comprising: receiving a voltage at a gate of an antifuse device; and coupling the antifuse device to a bit line using both the first transistor and the second transistor.
Drawings
Various aspects of the invention are best understood from the following detailed description when read with the accompanying drawing figures. It should be noted that, in accordance with standard practice in the industry, various components are not drawn to scale. In fact, the dimensions of the various elements may be arbitrarily increased or decreased for clarity of discussion.
Fig. 1A-1F are diagrams of antifuse devices according to some embodiments.
Fig. 2A-2D are diagrams of antifuse devices according to some embodiments.
Fig. 3 is a flow diagram of a method of operating a circuit according to some embodiments.
FIG. 4 is a flow chart of a method of fabricating an antifuse device according to some embodiments.
Fig. 5 is a flow diagram of a method of generating an IC layout diagram according to some embodiments.
Fig. 6A and 6B illustrate anti-fuse cell layout diagrams in accordance with some embodiments.
Fig. 7 is a block diagram of an Electronic Design Automation (EDA) system in accordance with some embodiments.
FIG. 8 is a block diagram of an IC manufacturing system and its associated IC manufacturing flow, in accordance with some embodiments.
Detailed Description
The following disclosure provides many different embodiments, or examples, for implementing different features of the provided subject matter. Specific examples of components and arrangements are described below to simplify the present disclosure. These are, of course, merely examples and are not intended to limit the invention. For example, in the following description, forming a first feature over or on a second feature may include embodiments in which the first and second features are formed in direct contact, and may also include embodiments in which additional features may be formed between the first and second features, such that the first and second features may not be in direct contact. Further, the present invention may repeat reference numerals and/or characters in the various embodiments. This repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various embodiments and/or configurations discussed.
Also, spatially relative terms, such as "below …," "below …," "lower," "above …," "upper," and the like, may be used herein for ease of description to describe one element or component's relationship to another element (or other) component as illustrated. Spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.
In various embodiments, an antifuse cell includes an antifuse device and two select transistors configured to couple the antifuse device in common to a bit line. The combination of the two transistors enables a more uniform electric field application in the programming operation than a single transistor approach to coupling the antifuse device to the bit line. In a read operation, the resulting parallel current path enables lower path resistance, reduced effects of device resistance variations, and increased current flow, as compared to a single transistor approach of coupling an antifuse device to a bit line, thereby improving accuracy in detecting a programmed state.
Fig. 1A-1F are diagrams of an
Fig. 1A, 1D, and 1E show cross-sectional views of the
Each of fig. 1A-1F shows currents IBL1 and IBL2 generated in response to applied voltages during operation of the
The illustration of the
As shown in fig. 1A to 1F, the
The
In some embodiments, the active area AA is electrically isolated from other elements in the
The S/D structures SD1-SD4 are semiconductor structures configured to have a doping type opposite to that of other portions of the active area AA. In the embodiment shown in fig. 1A-1F, the active area AA has a p-type doping and the S/D structures SD1-SD4 have an n-type doping, represented as diodes D1 and D2 of fig. 1E and 1F.
In some embodiments, the S/D structure is configured to have a lower resistivity than other portions of the active area AA. In some embodiments, the S/D structures SD1-SD4 include one or more portions having a doping concentration greater than one or more doping concentrations present throughout the active region AA. In various embodiments, the S/D structures SD1-SD4 include epitaxial regions of semiconductor material, such as silicon, silicon germanium (SiGe), and/or silicon carbide (SiC).
The transistor MNR0 includes at least part of the S/D structure SD1, part of the S/D structure SD2, and part of the active area AA between the S/D structures SD1 and SD 2; the antifuse device MNP0 includes a portion of the S/D structure SD2, a portion of the S/D structure SD3, and a portion of the active area AA between the S/D structures SD2 and SD 3; and the transistor MNR1 includes a portion of the S/D structure SD3, at least a portion of the S/D structure SD4, and a portion of the active area AA between the S/D structures SD3 and SD 4. Thus, the antifuse device MNP0 shares the S/D structure SD2 with transistor MNR0 and the S/D structure SD3 with transistor MNR 1. In various embodiments, the transistor MNR0 shares the S/D structure SD1 with at least one other IC device (not shown) and/or the transistor MNR1 shares the S/D structure SD4 with at least one other IC device (not shown).
The transistor MNR0 includes a gate structure GR0 located over a dielectric layer (not labeled) and a portion of each of the S/D structures SD1 and SD2 along the Z-direction. Thus, the portion of the active area AA directly below the gate structure GR0 and between the S/D structures SD1 and SD2 is configured as the channel of the transistor MNR0 (not shown). In various embodiments, the gate structure GR0 extends in the positive and/or negative Y-direction and is included in one or more transistors (not shown) in addition to the transistor MNR 0.
The transistor MNR1 includes a gate structure GR1 overlying a dielectric layer (not labeled) and portions of each of the S/D structures SD3 and SD4 along the Z-direction. Thus, the portion of the active area AA directly below the gate structure GR1 and between the S/D structures SD3 and SD4 is configured as the channel of the transistor MNR1 (not shown). In various embodiments, the gate structure GR1 extends in the positive and/or negative Y-direction and is included in one or more transistors (not shown) in addition to the transistor MNR 1.
The antifuse device MNP0 includes a gate structure GP0 located over a dielectric layer OXP and portions of each of the S/D structures SD2 and SD3 along the Z-direction. Thus, the S/D structures SD2 and SD3 are configured to control the voltage levels of the portions of the active area AA directly below the gate structure GP0 and the dielectric layer OXP and between the S/D structures SD2 and SD 3. In various embodiments, in addition to the antifuse device MNP0, the gate structure GP0 extends in the positive and/or negative Y-direction and is included in one or more antifuse devices (not shown).
Each of the gate structures GR0, GR1, and GP0 is a roll comprising one or more conductive materials (e.g., polysilicon, one or more metals, and/or one or more other suitable materials) substantially surrounded by one or more insulating materials (e.g., silicon dioxide and/or one or more other suitable materials), and thereby configured to control a voltage provided to an underlying dielectric layer (e.g., dielectric layer OXP) of the
The dielectric layer OXP comprises one or more layers of dielectric material configured such that, in operation, a sufficiently large electric field across the dielectric layer can sustainably alter at least one of the dielectric materials, thereby significantly reducing the resistance of the dielectric layer from the level prior to application of the electric field. In some embodiments, the dielectric material may be continuously changed, also referred to as breaking through the dielectric material or programming the antifuse device MNP0 and/or the
In various embodiments, the dielectric layer OXP comprises one or more of silicon dioxide and/or a high-k dielectric material (e.g., a dielectric material having a k value greater than 3.8 or 7.0). In some embodiments, the high-k dielectric material comprises aluminum oxide, hafnium oxide, lanthanum oxide, or other suitable materials.
The
A conductive path, such as conductive path WLP0, is one or more conductive elements configured to provide a low resistance electrical connection between the first and second circuit elements. In various embodiments, the conductive elements (also referred to as conductors) are IC structures that include one or more conductive materials, such as copper, tungsten, aluminum, gold, titanium, polysilicon, or other materials suitable for forming low resistance paths. In some embodiments, the conductive elements are segments of a metal zero layer used in the fabrication process for forming the
The conductive path WLP0 (also referred to as a conductive or bias voltage line in some embodiments) is configured as at least a portion of a low resistance electrical connection between the via structure V2 and a first voltage source (not shown) external to the
The
In the embodiment shown in fig. 1B, the via structures V1 and V3 are configured to electrically connect the respective gate structures GR0 and GR1 to the conductive path WLR1 through a single conductive element WLRM0, and thereby couple the gate structures GR0 and GR1 to each other. In some embodiments, the via structures V1 and V3 are configured to electrically connect the respective gate structures GR0 and GR1 to the conductive path WLR1, and thereby couple the gate structures GR0 and GR1 to each other through one or more conductive elements in addition to or instead of the conductive element WLRM 0.
A conductive path WLR1 (also referred to as a select signal line in some embodiments) is configured to electrically connect the gate structures GR0 and GR1 to a second voltage source (not shown) external to the
The
A conductive path BL (also referred to as a bit line in some embodiments) is schematically represented in fig. 1A and 1C-1F, and is configured to electrically connect the contact structure C1 to a third voltage source (not shown) external to the
The
In some embodiments, the contact structures C1 and C2 are electrically connected to the same conductive element of the conductive path BL, and the S/D structures SD1 and SD4 are thereby configured to receive the voltage BLV from the conductive path BL through the respective contact structures C1 and C2. In some embodiments, the contact structures C1 and C2 are electrically connected to individual conductive elements of the conductive path BL, and the S/D structures SD1 and SD4 are additionally configured to receive the voltage BLV from the conductive path BL through the respective contact structures C1 and C2.
In operation, the transistors MNR0 and MNR1 are thus configured to be simultaneously turned on or off in response to the voltage WLR1V received at the respective gate structures GR0 and GR1 and the voltage BLV received at the respective S/D structures SD1 and SD 4. In the embodiment shown in fig. 1A-1F, each of transistors MNR0 and MNR1 is an n-type transistor and turns on in response to the value of voltage WLR1V being higher than the value of voltage BLV by an amount equal to or greater than the threshold voltage of the respective one of transistors MNR0 or MNR 1.
In some embodiments, each of transistors MNR0 and MNR1 is a p-type transistor and turns on in response to the value of voltage WLR1V being lower than the value of voltage BLV by an amount equal to or greater than the threshold voltage of the respective one of transistors MNR0 or MNR 1. In various embodiments, the threshold voltages of the transistors MNR0 and MNR1 are the same voltage value or have different values from each other.
With the configuration of the
In operation, transistor MNR0 turns on to make the corresponding channel conductive, allowing voltage BLV to be transferred from S/D structure SD1 to S/D structure SD2 and current IBL1 to flow from S/D structure SD2 to S/D structure SD1 through the low resistance path of the channel. Transistor MNR1 turns on to make the corresponding channel conductive, allowing voltage BLV to be transferred from S/D structure SD4 to S/D structure SD3 and current IBL2 to flow from S/D structure SD3 to S/D structure SD4 through the low resistance path of the channel.
In operation, when the transistors MNR0 and MNR1 are turned on, the voltage WLP0V at the gate structure GP0 causes a current Ic to flow through the dielectric layer OXP. The magnitude and polarity of current Ic is determined based on the magnitude and polarity of the difference between the values of voltage WLP0V and BLV. In the embodiment illustrated in fig. 1A-1F, a positive value of current Ic indicates that voltage WLP0V is greater in value than voltage BLV.
The current IBL1 is the first component of the current Ic and flows in the negative X direction from the antifuse device MNP0 to the S/D structure SD 1. The current IBL2 is the second component of the current Ic and flows in the positive X direction from the antifuse device MNP0 to the S/D structure SD 4. The sum of the currents IBL1 and IBL2 is equal to the current Ic and the current IBL in the conductive path BL.
The relative magnitudes of the currents IBL1 and IBL2 are based on the resistance values of the respective current paths between the gate structure GP0 and the conductive path BL. Based on the configuration discussed above, the
In comparison to a method in which a single transistor couples the antifuse device to the bitline through a single current path, the
FIG. 1D illustrates an operation in which voltages WLP0V and BLV are applied to
Thus, as shown in FIG. 1D, in operation, the voltage BLV received at S/D structure SD1 is deemed to be received at S/D structure SD2 via turn-on transistor MNR0, and the voltage BLV received at S/D structure SD4 is deemed to be received at S/D structure SD3 via turn-on transistor MNR 1. In response to the difference between the values of the voltage VLP0V at the gate structure GP0 and the voltage BLV at the S/D structures SD2 and SD3, a total electric field is generated in the antifuse device MNP0, a portion of which is in the active region AA and is represented in fig. 1D as electric field EF.
In the embodiment shown in fig. 1D, because transistors MNR0 and MNR1 are symmetrically configured in the X-direction relative to antifuse device MNP0, in operation, voltage BLV at S/D structures SD2 and SD3 causes electric field EF to have a symmetric profile between S/D structures SD2 and SD 3.
As shown in fig. 1D, the symmetric profile of the electric field EF includes a first field strength at each of the S/D structures SD2 and SD3, and a second field strength at the center of the portion of the active region AA between the S/D structures SD2 and SD3 and directly below the gate structure GP0, the second field strength being lower than the first field strength.
In some embodiments, the transistors MNR0 and MNR1 are asymmetrically configured in the X-direction relative to the antifuse device MNP0, and in operation, the voltage BLV at the S/D structures SD2 and SD3 causes the electric field EF to have an asymmetric profile between the S/D structures SD2 and SD3 (which varies between one or both field strengths at the S/D structures SD2 and SD 3) and a lower field strength at a point between the S/D structures SD2 and SD 3.
In a method of applying a voltage to an unprogrammed antifuse device using a single transistor, the generated electric field has an asymmetric profile, and the resulting electric field has an asymmetric profile, wherein the field strength adjacent to the transistor continuously decreases with increasing distance from the transistor. In contrast to this single transistor approach, the
During a programming operation, the location at which dielectric breakdown occurs is a function of the dielectric material and the strength of the electric field throughout the dielectric layer. By improving the uniformity of the electric field, the
FIG. 1E illustrates an operation in which voltages WLP0V and BLV are applied to
Thus, the resistor Rb0 and the diode D0 coupled in series between the resistor Rox and the transistor MNR0 are configured as a first current path through which the current IBL1 flows in operation. Thus, the resistor Rb1 and the diode D1 coupled in series between the resistor Rox and the transistor MNR1 are configured as a second current path through which the current IBL2 flows in operation. The first and second current paths are arranged in parallel such that, in operation, the total current IBL is a function of the parallel combination of resistors Rb0 and Rb1, except for the difference between the voltages WLP0V and BLV versus the voltage drop across diodes D0 and D1.
In the case where the resistor Rox corresponds to the breakdown of the center of the dielectric layer OXP in the X direction, the resistors Rb0 and Rb1 have an equal resistance value equal to about half the total resistance value of the active area AA between the S/D structures SD2 and SD 3. In this case, the parallel combination of resistors Rb0 and Rb1 has an equivalent resistance value equal to about one-quarter of the total resistance value. In some embodiments, the center of the dielectric layer OXP in the X-direction corresponds to the midpoint between the S/D structures SD2 and SD 3.
In the case where the resistor Rox corresponds to the breakdown of the dielectric layer OXP at a position other than the center in the X direction, one of the resistors Rb0 or Rb1 has a value equal to less than half of the total resistance value, and the equivalent resistance value of the parallel combination of the resistors Rb0 and Rb1 is less than one-fourth of the total resistance value.
Thus, in the programmed state, the maximum equivalent substrate resistance of the parallel current path configuration of the
In a method of applying a voltage to a programmed antifuse device using a single transistor, the resulting single current path may have a resistance value that varies from less than one-fourth of the total substrate resistance to a value close to the entire substrate resistance, depending on the location of dielectric breakdown. In comparison to this single transistor approach, the
Fig. 2A-2C are diagrams of an
Fig. 2A shows a cross-sectional view of the
The illustration of the
The
The antifuse device MNP1, transistors MNR2 and MNR3, S/D structures SD4-SD7, contact structure C3, via structures V4-V6, conductive element WLRM1, and conductive paths WLR2 and WLP1 have configurations corresponding to the antifuse device MNP0, transistors MNR0 and MNR1, S/D structures SD1-SD4, contact structures C1 and C2, via structures V1-V3, conductive element WLRM0, and conductive paths WLR1 and WLP0, respectively, as discussed above with reference to fig. 1A-1F; therefore, their detailed description is omitted.
Fig. 2A-2D illustrate currents IBL1 and IBL2, and fig. 2A-2D illustrate currents IBL, each discussed above with reference to fig. 1A-1F. Fig. 2A-2D also show currents IBL3 and IBL4 discussed below.
As shown in fig. 2A to 2D, each of the transistors MNR1 and MNR2 includes a partial S/D structure SD4, so that the transistors MNR1 and MNR2 share the S/D structure SD 4. Similarly, the antifuse device MNP1 shares the S/D structure SD5 with transistor MNR2 and the S/D structure SD6 with transistor MNR 3. In some embodiments, transistor MNR3 shares S/D structure SD7 with at least one other IC device (not shown).
A via structure V5 overlies the gate structure (not labeled) of the antifuse device MNP1 and electrically connects it to a conductive path WLP 1. Via structure V5 is shown in fig. 2B and 2C and is included in the schematic representation of conductive path WLP1 shown in fig. 2A and 2D.
The conductive path WLP1 (also referred to as a conductive or bias voltage line in some embodiments) is configured as at least a portion of a low resistance electrical connection between the via structure V5 and a fourth voltage source (not shown) external to the
Via structure V4 overlies the gate structure (not labeled) of transistor MNR2 and electrically connects it to conductive element WLRM1, and via structure V6 overlies the gate structure (not labeled) of transistor MNR3 and electrically connects it to conductive element WLRM 1. Conductive element WLRM1 is part of conductive path WLR 2. Via structures V4 and V6 and conductive element WLRM1 are shown in fig. 2B and 2C and are included in the schematic representation of conductive path WLP2 shown in fig. 2A and 2D.
In the embodiment shown in fig. 2B and 2C, the via structures V4 and V6 are configured to electrically connect the gate structures of the transistors MNR2 and MNR3 to the conductive path WLR2 through a single conductive element WLRM1, and thus couple the gate structures of the transistors MNR2 and MNR3 to each other. In some embodiments, the via structures V4 and V6 are configured to electrically connect respective gate structures of the transistors MNR2 and MNR3 to the conductive path WLR2, and thus couple the gate structures of the transistors MNR2 and MNR3 to each other through one or more conductive elements in addition to or instead of the conductive element WLRM 1.
A conductive path WLR2 (also referred to as a select signal line in some embodiments) is configured to electrically connect the gate structures of the transistors MNR2 and MNR3 to a fifth voltage source (not shown) external to the
The contact structure C3 is located over the S/D structure SD7 and is configured to electrically connect the S/D structure SD7 to the conductive path BL. The S/D structure SD7 of transistor MNR3 is thus configured to receive, in operation, a voltage BLV from the third voltage source.
In some embodiments, contact structures C1, C2, and C3 are electrically connected to the same conductive element of conductive path BL, and S/D structures SD1, SD4, and SD7 are thereby configured to receive voltage BLV from conductive path BL through respective contact structures C1, C2, and C7. In various embodiments, one or more of the contact structures C1, C2, and C3 are electrically connected to individual conductive elements of the conductive path BL, and the S/D structures SD1, SD4, and SD7 are additionally configured to receive the voltage BLV from the conductive path BL through the respective contact structures C1, C2, and C3.
Fig. 2B shows IC device 200-1, in an embodiment of
In the embodiment shown in fig. 2B, the via structures V1, V3, V4 and V6 and the conductive elements WLRM0 and WLRM1 are aligned with each other in the X-direction, and the via structures V2 and V5 are aligned with each other in the X-direction. In various embodiments, one or more of via structures V1, V3, V4, and/or V6 and/or conductive elements WLRM0 and/or WLRM1 are not aligned in the X-direction with another one or more of via structures V1, V3, V4, and/or V6 and/or conductive elements WLRM0 and/or WLRM1, and/or via structures V2 and V5 are not aligned in the X-direction with respect to each other.
Fig. 2C shows IC device 200-2, in an embodiment of
In the embodiment shown in fig. 2C, the via structures V1, V3 and V5 and the conductive element WLRM0 are aligned with each other in the X-direction, and the via structures V2, V4 and V6 and the conductive element WLRM1 are aligned with each other in the X-direction. In various embodiments, one or more of via structures V1, V3 and/or V5 and/or conductive element WLRM0 is not aligned in the X-direction with another one or more of via structures V1, V3 and/or V5 and/or conductive element WLRM0, and/or one or more of via structures V2, V4 and/or V6 and/or conductive element WLRM1 is not aligned in the X-direction with another one or more of via structures V2, V4 and/or V6 and/or conductive element WLRM 1.
In operation, as described above, the transistors MNR2 and MNR3 are configured to be simultaneously turned on or off in response to the voltage WLR2V received at their respective gate structures and the voltage BLV received at the respective S/D structures SD4 and SD7, in the manner discussed above with reference to the transistors MNR0 and MNR 1. When the transistors MNR2 and MNR3 are turned on, the voltage WLP1V at the gate structure of the antifuse device MNP1 biases the antifuse device MNP1 in the manner discussed above with reference to the antifuse device MNP0, and generates currents IBL3 and IBL4 that flow as shown in fig. 2A-2D and in the manner discussed above with reference to the respective currents IBL1 and IBL 2.
Thus, in operation, current IBL3 flows in the negative X direction from the antifuse device MNP1 to the S/D structure SD4, current IBL4 flows in the positive X direction from the antifuse device MNP1 to the S/D structure SD7, and the sum of the currents IBL3 and IBL4 is equal to the current IBL in the conductive path BL.
The
In the embodiment illustrated in fig. 2A-2D, the
With the configuration discussed above, the
Fig. 3 is a flow diagram of a
In some embodiments, operating the circuit using the
The sequence of operations of
In
In some embodiments, the antifuse device is one of a plurality of antifuse devices, and receiving the voltage includes selecting the antifuse device from the plurality of antifuse devices. In some embodiments, receiving a voltage includes receiving a voltage at a gate of a subset (e.g., a column) of the plurality of antifuse devices.
In various embodiments, receiving the voltage includes receiving the voltage WLP0V at the gate structure GP0 of the antifuse device MNP0, as discussed above with reference to fig. 1A-2D, or receiving the voltage WLP0V at the gate structure of the antifuse device MNP1, as discussed above with reference to fig. 2A-2D.
In some embodiments, receiving the voltage includes receiving the voltage through a via structure. In some embodiments, receiving a voltage through a via structure includes receiving a voltage through a via structure V2 or V5, as discussed above with reference to fig. 1A-2D.
In
In some embodiments, coupling the antifuse device to the bitline includes coupling the antifuse device MNP0 to the conductive path BL using transistors MNR0 and MNR1, as discussed above with reference to fig. 1A-2D, or coupling the antifuse device MNP1 to the conductive path BL using transistors MNR2 and MNR3, as discussed above with reference to fig. 2A-2D.
In some embodiments, using the first transistor and the second transistor simultaneously includes receiving a same signal at a gate of the first transistor and a gate of the second transistor. In some embodiments, receiving the same signal includes the first transistor receiving the signal through the first via and the second transistor receiving the signal through the second via. In some embodiments, receiving a signal through a first via includes receiving a signal from a conductive element (e.g., a metal segment), and receiving a signal through a second via includes receiving a signal from the same conductive element. In various embodiments, receiving a signal from a conductive element includes receiving a signal from conductive element WLRM0 or WLRM1, as discussed above with reference to fig. 1B, 2B, and 2C.
In some embodiments, the first and second transistors are one of a plurality of transistor pairs, and receiving the same signal includes selecting the first and second transistors from the plurality of transistor pairs. In some embodiments, receiving the same signal includes receiving one of a plurality of signals corresponding to a subset (e.g., a row or a word) of the plurality of antifuse devices corresponding to the plurality of transistor pairs. In some embodiments, receiving the same signal includes receiving one of the voltages WLR1V or WLR2V, as discussed above with reference to fig. 1A-2D.
In some embodiments, coupling the antifuse device to the bit line includes the antifuse device receiving a voltage from the bit line. In some embodiments, receiving the voltage from the bit line includes transmitting the voltage from the first S/D structure of the first transistor to an S/D structure shared by the first transistor and the antifuse device, and transmitting the voltage from the first S/D structure of the second transistor to an S/D structure shared by the second transistor and the antifuse device. In some embodiments, receiving the voltage from the bit line includes receiving the voltage BLV from the conductive path BL, as discussed above with reference to fig. 1A-2D.
In some embodiments, coupling the antifuse device to the bit line includes changing the antifuse device from an unprogrammed state to a programmed state. In some embodiments, coupling the antifuse device to the bit line includes applying an electric field to a dielectric layer of the antifuse device, the electric field having a symmetry based on the first transistor and the second transistor. In some embodiments, coupling the antifuse device to the bit line includes programming the antifuse device by breaking down a dielectric layer between the gate and a portion of the substrate located between the first transistor and the second transistor. In some embodiments, coupling the antifuse device to the bit line includes applying an electric field to the dielectric layer OXP, as discussed above with reference to fig. 1A-2D.
In some embodiments, coupling the antifuse device to the bit line includes generating a current in the bit line, the current including a first component flowing through the first transistor in a first direction and a second component flowing through the second transistor in a second direction opposite the first direction. In some embodiments, the first component flows through the first contact structure, the second component flows through the second contact structure, and the antifuse device and the first and second transistors are positioned between the first and second contact structures. In some embodiments, the first and second components flow through contact structures C1 and C2 or through contact structures C2 and C3, as discussed above with reference to fig. 1A-2D.
In some embodiments, generating the current in the bit line includes generating the current at a breakdown location in a dielectric layer of the antifuse device. In some embodiments, generating the current in the bit line includes generating the current through the parallel substrate current path based on a location of the dielectric breakdown. The parallel substrate current path has an equivalent substrate resistance value based on a dielectric breakdown location, and the generated current is based on a maximum equivalent substrate resistance value corresponding to the dielectric breakdown location at a midpoint between the first and second transistors. In some embodiments, generating the current in the bit line includes generating the current based on resistors Rb0 and Rb1, as discussed above with reference to fig. 1E and 1F.
In some embodiments, the antifuse device is one of a plurality of antifuse devices (e.g., an antifuse array), and generating the current in the bit line includes generating the current as part of a read operation on the plurality of antifuse devices.
In
In various embodiments, receiving the second voltage at the gate of the second antifuse device includes receiving the second voltage at the second antifuse device in the same active region as the antifuse device or in an active region different from the active region of the antifuse device.
In various embodiments, coupling the second antifuse device to the second bit line includes coupling the antifuse and the second antifuse device to the same bit line or to different bit lines.
In some embodiments, receiving the second voltage includes receiving the voltage WLP1 at the gate of the antifuse device MNP1, and using the third and fourth transistors includes using the transistors MNR2 and MNR3, as discussed above with reference to fig. 2A-2D.
In some embodiments, coupling the second antifuse device to the second bit line includes generating a second current in the second bit line, the second current including a first component flowing through the third transistor in the second direction and a second component flowing through the fourth transistor in the first direction. In some embodiments, the first component of the second current flows through a contact structure shared between a third transistor and a second transistor of the antifuse device.
In some embodiments, the first component of the second current flows through the contact structure C2 shared between the transistor MNR2 and the transistor MNR1 of the antifuse device MNP0, as discussed above with reference to fig. 2A-2D.
By performing some or all of the operations of the
Figure 4 is a flow diagram of a
The sequence of operations of
In some embodiments, one or more operations of
In
Forming the first and second S/D structures includes performing one or more fabrication operations in accordance with forming the S/D structures SD2 and SD3 and the active area AA, as discussed above with reference to fig. 1A-2D. Forming the first gate structure includes performing one or more fabrication operations in accordance with forming the gate structure GP0, and thereby forming the antifuse device includes performing one or more fabrication operations in accordance with forming the antifuse device MNP0, as discussed above with reference to fig. 1A-2D.
In some embodiments, forming the antifuse device includes establishing an electrical connection between the first gate structure and a conductive path configured to carry a first voltage. Building an electrical connection includes performing one or more fabrication operations according to the build via structure V2, and in some embodiments, according to some or all of the conductive paths WLP0, as discussed above with reference to fig. 1A-2D.
In some embodiments, forming the antifuse device includes forming one antifuse device as part of forming a plurality of antifuse devices (e.g., an array of antifuse devices).
In
Forming the first transistor includes forming a second gate structure and a third S/D structure in the active region, the second gate structure partially overlying each of the first and third S/D structures. Forming the second transistor includes forming a third gate structure and a fourth S/D structure in the active region, the third gate structure partially overlying each of the second and fourth S/D structures.
Forming the third and fourth S/D structures includes performing one or more fabrication operations in accordance with forming the S/D structures SD1 and SD4, as discussed above with reference to fig. 1A-2D. Forming the second and third gate structures includes performing one or more fabrication operations in accordance with forming respective gate structures GR0 and GR1, and thereby forming the first and second transistors includes performing one or more fabrication operations in accordance with forming respective transistors MNR0 and MNR1, as discussed above with reference to fig. 1A-2D.
In some embodiments, forming the first and second transistors includes forming one transistor pair as part of a plurality of transistor pairs forming a corresponding plurality of antifuse devices (e.g., an array of antifuse devices).
In
In some embodiments, constructing the electrical connection includes constructing the conductive segment in a metal zero layer of the manufacturing process. In some embodiments, establishing the electrical connection includes performing one or more fabrication operations in accordance with forming the conductive element WLRM0, as discussed above with reference to fig. 1A-2D.
In some embodiments, establishing electrical connections includes establishing electrical connections between gates of one transistor pair as part of establishing electrical connections between gates of a plurality of transistor pairs of a corresponding plurality of antifuse devices (e.g., an array of antifuse devices).
In
In some embodiments, constructing the electrical connection includes constructing the conductive segment in a metal zero layer of the manufacturing process. In some embodiments, establishing the electrical connection includes performing one or more fabrication operations in accordance with forming the conductive path BL, as discussed above with reference to fig. 1A-2D.
In some embodiments, establishing electrical connections includes establishing electrical connections between S/D structures of one transistor pair as part of establishing electrical connections between S/D structures of a plurality of transistor pairs of a corresponding plurality of antifuse devices (e.g., an array of antifuse devices).
The operations of
Fig. 5 is a flow diagram of a
In some embodiments, some or all of
Some or all of the operations of
In some embodiments, the operations of
In some embodiments, fig. 6A and 6B are illustrations of non-limiting examples of respective IC layout diagrams 600A and 600B generated by performing one or more operations of
For clarity, the IC layout diagrams 600A and 600B are simplified. In various embodiments, one or more of
Each of the IC layout diagrams 600A and 600B corresponds to an antifuse cell, and includes a first cell bit CB1 that includes layout components corresponding to an antifuse device MNP0 and transistors MNR0 and MNR1 (as discussed above with reference to fig. 1A-2D), and a bitline region BLR discussed below. In some embodiments, one or both of
In the embodiment illustrated in fig. 6A and 6B, IC layout 600A includes second cell bit CB2A, and
Cell bit CB1 includes gate regions G1-G3 intersecting active regions AR, regions VR1-VR3 overlying respective gate regions G1-G3, conductive regions WLRR0 overlying via regions VR1 and VR3 and intersecting gate regions G1-G3, and contact regions CR1 and CR2 overlying active regions AR and underlying bit line regions BLR. In the embodiment shown in fig. 6A and 6B, the via regions VR1 and VR3 and the conductive region WLRR0 are located at positions distant from the active region AR in the positive Y direction, and the via region VR2 is located at positions distant from the active region AR in the negative Y direction. In some embodiments, the via regions VR1 and VR3 and the conductive region WLRR0 are located at a position away from the active region AR in the negative Y direction, and the via region VR2 is located at a position away from the active region AR in the positive Y direction.
Each of the cell bits CB2A and CB2B includes a gate region G4-G6 intersecting the active region AR, a via region VR4-VR6 located above the gate region G4-G6, a conductive region WLRR1 located above the via regions VR4 and VR6 and intersecting the gate region G4-G6, and contact regions CR2 and CR3 located below the active region AR and the bit line region BLR. The cell site CB2A includes via regions VR4 and VR6 and a conductive region WLRR1 aligned in the X direction with the via regions VR1 and VR3 and the conductive region WLRR0 of the cell site CB1, and a via region VR5 aligned in the X direction with the via region VR2 of the cell site CB 1. The cell bit CB2B includes a via region VR5 aligned with the via regions VR1 and VR3 and the conductive region WLRR0 of the cell bit CB1 in the X direction, and via regions VR4 and VR6 and the conductive region WLRR1 aligned with the via region VR2 of the cell bit CB1 in the X direction.
With the configuration shown in fig. 6A and 6B and discussed above, the active area AR and the contact area CR2 are included in each cell bit CB1, CB2A, and CB 2B. In some embodiments, a bit line region BLR is included in each cell bit CB1, CB2A, and CB 2B.
An active region (e.g., active area AR) is an area in an IC layout included in a fabrication process as part of defining an active region (also referred to as an oxide diffusion Or Definition (OD)) in a semiconductor in which one or more IC device components, such as source/drain regions, are formed. In various embodiments, the active region is an n-type or p-type active region of a planar transistor or a fin field effect transistor (FinFET). In some embodiments, active area AR is included in the manufacturing process as part of defining active area AA discussed above with reference to fig. 1A-2D.
The gate regions (e.g., gate regions G1-G6) are regions in an IC layout included in the fabrication process as part of defining a gate structure in an IC device that includes at least one of a conductive material or a dielectric material. In various embodiments, one or more gate structures corresponding to the gate region include at least one conductive material overlying at least one dielectric material. In some embodiments, the gate regions G1-G3 are included in the fabrication process as part of defining the respective gate structures GR0, GP0, and GR1 discussed above with reference to fig. 1A-2D, and the gate regions G4-G6 are included in the fabrication process as part of defining the gate structures of the transistor MNR2, the antifuse device MNP1, and the transistor MNR3, respectively, as discussed above with reference to fig. 2A-2D.
Conductive regions (e.g., conductive region WLRR0 or WLRR1 or bit line region BLR) are regions in an IC layout included in the fabrication process as part of one or more segments that define one or more conductive layers in the IC device. In various embodiments, one or more conductive regions (e.g., one or more of conductive region WLRR0 or WLRR1 or bit line region BLR) correspond to one or more sections of the same or different conductive layers in an IC device. In various embodiments, the conductive regions correspond to one or more of metal zero, metal one, or higher metal layers in the IC device. In some embodiments, the conductive regions WLRR0 or WLRR1 or bit line region BLR are included in the fabrication process as part of defining the conductive elements WLRM0 and WLRM1 and the conductive paths BL, respectively, as discussed above with reference to fig. 1A-2D.
Via regions (e.g., via regions VR1-VR6) are regions in an IC layout included in a fabrication process as part of one or more segments that define one or more conductive layers in an IC device that are configured to form an electrical connection between one or more conductive elements corresponding to a conductive region (e.g., conductive region WLRR0 or WLRR1) and a gate structure corresponding to a gate region (e.g., respective gate region G1-G6). In various embodiments, the one or more conductive layer segments formed based on the via regions include vias between respective gate structures and respective conductive elements in a metal layer (e.g., a metal zero layer) overlying the IC device. In some embodiments, the via regions VR1-VR6 are included in the fabrication process as part of defining the respective via structures V1-V6 discussed above with reference to fig. 1A-2D.
Contact regions (e.g., contact regions CR1-CR3) are regions in the IC layout included in the fabrication process as part of one or more segments that define one or more conductive layers in the IC device that are configured to form an electrical connection between one or more conductive elements based on conductive regions (e.g., bit line regions BLR) and active regions based on active regions (e.g., active regions AR). In various embodiments, the one or more conductive layer segments formed based on the contact regions include contacts between active region-based active regions in an overlying metal layer (e.g., a metal zero layer) of the IC device and one or more conductive elements based on the conductive regions. In some embodiments, contact regions CR1-CR3 are included in the fabrication process as part of defining respective contact structures C1-C3 discussed above with reference to fig. 1A-2D.
In
The first, second and third gate regions have a spacing corresponding to a gate pitch of the fabrication process such that the second gate region is offset from each of the first and third gate regions by a distance corresponding to the gate pitch.
Intersecting the active region with the first, second, and third gate regions includes extending each of the first, second, and third gate regions to a region outside the active region in a direction perpendicular to a direction in which the active region extends. In various embodiments, intersecting the active region with the first, second, and third gate regions includes extending one or more of the first, second, or third gate regions to intersect one or more active regions outside the active region.
In some embodiments, intersecting the active region with the first, second, and third gate regions is part of intersecting the active region with a plurality of gate regions, including one or more gate regions other than the first, second, and third gate regions. In some embodiments, the one or more additional gate regions comprise one or more dummy gate regions.
Defining the location of the antifuse structure in the active region includes defining a rectangular or other region available in the fabrication process for locating one or more dielectric layers that can be sustainably altered by a sufficiently strong electric field.
Defining the locations of the first and second transistors in the active area includes defining a rectangular or other area available in the fabrication process for positioning one or more dielectric layers capable of controlling the channel in the active area corresponding to the active area. Defining the location of each of the first and second transistors includes having each of the first and second transistors adjacent to an antifuse structure.
In the non-limiting example shown in fig. 6A and 6B, the intersection of the active region with the first, second, and third gate regions includes intersecting the active region AR with respective gate regions G1-G3. In some embodiments, intersecting the active region with the first, second, and third gate regions includes intersecting the active region AR with respective gate regions G4-G6.
In
In some embodiments, positioning the first and second contact regions over the active region is a portion of positioning a plurality of contact regions over the active region, the plurality of contact regions including one or more contact regions in addition to the first and second contact regions, and positioning one or more additional contact regions at one or more additional locations over the active region that define one or more electrical connections between the portion of the active region included in the one or more additional transistors and the one or more additional contact regions.
In the non-limiting example shown in fig. 6A and 6B, positioning the first and second contact regions over the active region includes positioning respective contact regions CR1 and CR2 over the active region. In some embodiments, positioning the first and second contact regions over the active area includes positioning the contact region CR3 over the active area AR.
In
Locating the first conductive region above the first contact region defines an electrical connection between the first contact region and the first conductive region, and locating the second conductive region above the second contact region defines an electrical connection between the second contact region and the first conductive region.
In some embodiments, the first and second contact regions are included in a plurality of contact regions including one or more contact regions in addition to the first and second contact regions, and the covered active region and the first and second contact regions include covering the one or more contact regions in addition to the first and second contact regions. Covering the one or more further contact areas defines one or more locations of electrical connection between the one or more additional contact areas and the first conductive area.
In the non-limiting example shown in fig. 6A and 6B, locating the first conductive region over the active region and the first and second contact regions includes locating the bit line region BLR over the active region AR and the contact regions CR1 and CR 2. In some embodiments, positioning the first conductive region over the active and first and second contact regions includes positioning the bit line region BLR over contact region CR 3.
In
The first via region is located above the first gate region defining an electrical connection between the first gate region and the first via region, the second via region is located above the second gate region defining an electrical connection between the second gate region and the second via region, and the third via region is located above the third gate region defining an electrical connection between the third gate region and the third via region.
In some embodiments, the respective first, second and third via regions overlying the first, second and third gate regions includes respective fourth, fifth and sixth via regions overlying the fourth, fifth and sixth gate regions, thereby defining locations for electrical connections between the fourth, fifth and sixth gate regions and the respective fourth, fifth and sixth via regions.
The second conductive region is located above the first and third via regions at a position defining an electrical connection between the first and second via regions and the second conductive region. In some embodiments, the third conductive region is located above the second via region defining an electrical connection between the second via region and the third conductive region.
In some embodiments, the second conductive region overlying the first and third via regions includes a fourth conductive region overlying the fourth and sixth via regions, thereby defining a location of electrical connection between the fourth and sixth via regions and the fourth conductive region. In some embodiments, the third conductive region overlying the second via region includes a fifth conductive region overlying the fifth via region, thereby defining an electrical connection between the fifth via region and the fifth conductive region.
In the non-limiting example shown in fig. 6A and 6B, the first, second and third via regions overlying the first, second and third gate regions include respective via regions VR1-VR3 overlying gate regions G1-G3, and the second conductive region overlying the first and third via regions includes conductive region WLRR0 overlying via regions VR1 and VR 3. In some embodiments, the third conductive region being located over the second via region includes the third conductive region (not shown) being located over the via region VR 2.
In the non-limiting example shown in fig. 6A and 6B, in some embodiments, the fourth, fifth, and sixth via regions overlying the fourth, fifth, and sixth gate regions include respective via regions VR4-VR6 overlying gate regions G4-G6, and the fourth conductive region overlying the fourth and sixth via regions includes conductive region WLRR1 overlying via regions VR4 and VR 6. In some embodiments, the fifth conductive region overlying the fifth via region includes a fifth conductive region (not shown) overlying the via region VR 5.
In
In
In
In
By performing some or all of the operations of
Fig. 7 is a block diagram of an Electronic Design Automation (EDA)
In some embodiments, the
In some embodiments, the
The
In one or more embodiments, the computer-
In one or more embodiments, the
The
The
In some embodiments, some or all of the mentioned processes and/or methods are implemented as stand-alone software applications for execution by a processor. In some embodiments, some or all of the referenced processes and/or methods are implemented as software applications as part of an add-on software application. In some embodiments, some or all of the referenced processes and/or methods are implemented as plug-ins to software applications. In some embodiments, at least one of the mentioned processes and/or methods is implemented as a software application that is part of an EDA tool. In some embodiments, some or all of the referenced processes and/or methods are implemented as software applications used by the
In some embodiments, the process is implemented as a function of a program stored in a non-transitory computer-readable recording medium. Examples of the non-transitory computer-readable recording medium include, but are not limited to, external/removable and/or internal/built-in memories or memory units, for example, one or more of an optical disk (such as a DVD), a magnetic disk (such as a hard disk), a semiconductor memory (such as a ROM, a RAM, a memory card), and the like.
Fig. 8 is a block diagram of an Integrated Circuit (IC) manufacturing system 800 and its associated IC manufacturing flow, according to some embodiments. In some embodiments, at least one of (a) one or more semiconductor masks or (B) at least one component in a layer of a semiconductor integrated circuit is fabricated using the fabrication system 800 based on a layout map.
In fig. 8, IC manufacturing system 800 includes entities that interact with each other during design, development, and manufacturing cycles, such as design room 820, mask room 830, and IC manufacturer/manufacturer ("fab") 850 and/or services related to manufacturing IC devices 860. The entities in system 800 are connected by a communication network. In some embodiments, the communication network is a single network. In some embodiments, the communication network is a variety of different networks, such as an intranet and the internet. The communication network includes wired and/or wireless communication channels. Each entity interacts with and provides services to and/or receives services from one or more other entities. In some embodiments, two or more of the design chamber 820, the mask chamber 830, and the IC fab 850 are owned by a single larger company. In some embodiments, two or more of the design chamber 820, the mask chamber 830, and the IC fab 850 coexist in a common facility and use common resources.
A design room (or design team) 820 generates an IC design layout 822. IC design layout 822 includes various geometric patterns (e.g., IC layout diagrams 600A and 600B discussed above with reference to fig. 6A and 6B) designed for IC device 860 (e.g., discussed above with reference to fig. 1A-2D). The geometric pattern corresponds to the pattern of the metal, oxide or semiconductor layers that make up the various components of the IC device 860 to be fabricated. The various layers combine to form various IC components. For example, portions of IC design layout 822 include various IC components formed in a semiconductor substrate (such as a silicon wafer), such as active regions, gate electrodes, sources and drains, metal lines or vias for inter-level interconnects, and openings for bond pads; and various material layers disposed on the semiconductor substrate. The design room 820 implements the appropriate design procedures to form the IC design layout 822. The design program includes one or more of a logical design, a physical design, or a place and route. The IC design layout 822 is presented in one or more data files with information of geometric patterns. For example, the IC design layout 822 may be represented in a GDSII file format or a DFII file format.
Mask chamber 830 includes data preparation 832 and mask fabrication 844. The mask chamber 830 uses the IC design layout 822 to fabricate one or more masks for fabricating the various layers of the IC device 860 according to the IC design layout 822. The mask chamber 830 performs mask data preparation 832 in which the IC design layout 822 is converted to a representative data file ("RDF"). The mask data preparation 832 provides the RDF to the mask manufacturer 844. Mask making 844 includes a mask writer. The mask writer converts the RDF into an image on a substrate, such as a mask (reticle) or a semiconductor wafer. Mask data preparation 832 manipulates design layout 822 to conform to the specific characteristics of a mask writer and/or the requirements of IC fabrication 850. In fig. 8, mask data preparation 832 and mask fabrication 844 are shown as separate elements. In some embodiments, mask data preparation 832 and mask fabrication 844 may be collectively referred to as mask data preparation.
In some embodiments, mask data preparation 832 includes Optical Proximity Correction (OPC), which uses lithographic enhancement techniques to compensate for image errors such as may be caused by diffraction, interference, other process effects, and the like. The OPC adjusts the IC design layout 822. In some embodiments, the mask data preparation 832 includes further Resolution Enhancement Techniques (RET), such as off-axis illumination, sub-resolution assist features, phase shifting masks, other suitable techniques, or the like or combinations thereof. In some embodiments, Inverse Lithography (ILT) is also used, which treats OPC as an inverse imaging problem.
In some embodiments, the mask data preparation 832 includes a Mask Rule Checker (MRC) that checks the IC design layout 822 that has undergone the process in OPC with a set of mask creation rules that include specific geometric and/or connection constraints to ensure sufficient margin to account for variability in the semiconductor manufacturing process, etc. In some embodiments, the MRC modifies the IC design layout 822 to compensate for constraints during mask manufacturing 844, which may undo part of the modification of the OPC implementation to meet mask creation rules.
In some embodiments, mask data preparation 832 includes a Lithography Process Check (LPC) that simulates the processing to be performed by IC fab 850 to fabricate IC device 860. The LPC models the process based on the IC design layout 822 to create a simulated fabricated device such as IC device 860. The process parameters in the LPC simulation may include parameters associated with individual processes of the IC fabrication cycle, parameters associated with the tool used to fabricate the IC, and/or other aspects of the fabrication process. LPC takes into account various factors such as spatial image contrast, depth of focus ("DOF"), mask error enhancement factor ("MEEF"), other suitable factors, and the like, or combinations thereof. In some embodiments, after creating a simulated fabricated device by LPC, if the shapes of the simulated devices are not close enough to meet the design rules, OPC and/or MRC will be repeated to further refine the IC design layout 822.
It should be appreciated that the above description of mask data preparation 832 has been simplified for the sake of brevity. In some embodiments, data preparation 832 includes additional features such as Logic Operations (LOPs) to modify IC design layout 822 according to manufacturing rules. Further, the processes applied to the IC design layout 822 during the data preparation 832 may be performed in a variety of different orders.
After mask data preparation 832 and during mask fabrication 844, mask 845 or mask set 845 is fabricated based on modified IC design layout 822. In some embodiments, mask fabrication 844 implements one or more lithographic exposures based on the IC design layout 822. In some embodiments, an e-beam or multiple e-beam mechanism is used to pattern on mask (photomask or reticle) 845 based on modified IC design layout 822. Various techniques may be employed to form mask 845. In some embodiments, mask 845 is formed using a binary technique. In some embodiments, the mask pattern includes opaque regions and transparent regions. A radiation beam, such as an Ultraviolet (UV) beam, used to expose a layer of image sensitive material (e.g., photoresist) that has been coated on the wafer is blocked by the opaque regions and passes through the transparent regions. In one example, the binary mask 845 includes a transparent substrate (e.g., quartz glass) and an opaque material (e.g., chrome) coated in opaque regions of the binary mask. In another example, mask 845 is formed using a phase-shift technique. In a Phase Shift Mask (PSM) version of mask 845, various features in the pattern formed on the phase shift mask are configured to have appropriate phase differences to improve resolution and imaging quality. In various examples, the phase shift mask may be an attenuated PSM or an alternating PSM. The resulting mask is used in various processes by mask making 844. Such masks may be used, for example, in ion implantation processes to form various doped regions in semiconductor wafer 853, in etching processes to form various etched regions in semiconductor wafer 853, and/or in other suitable processes.
IC fab 850 includes wafer fabrication 852. IC fab 850 is an IC fabrication facility that includes one or more fabrication facilities for fabricating a variety of different IC products. In some embodiments, IC fab 850 is a semiconductor foundry. For example, there may be a manufacturing facility for front end of line (FEOL) manufacturing of a plurality of IC products, while a second manufacturing facility may provide back end of line (BEOL) manufacturing for interconnection and packaging of IC products, and a third manufacturing facility may provide other services for a foundry.
IC fab 850 uses mask (or masks) 845, produced by mask chamber 830, to fabricate IC device 860. Thus, IC foundry 850 uses, at least indirectly, IC design layout 822 to fabricate IC device 860. In some embodiments, semiconductor wafer 853 is fabricated by IC fab 850 using mask (or masks) 845 to form IC device 860. In some embodiments, IC fabrication includes performing one or more lithographic exposures based at least indirectly on the IC design layout 822. Semiconductor wafer 853 comprises a silicon substrate or other suitable substrate having a layer of material formed thereon. The semiconductor wafer 852 also includes one or more of various doped regions, dielectric features, multilayer interconnects, etc. (formed in subsequent fabrication steps).
For example, details regarding Integrated Circuit (IC) manufacturing systems (e.g., system 800 of fig. 8) and their associated IC manufacturing flows are found in the following patents: united states patent number 9,256,709 issued on 9/2/2016, united states patent number 20150278429 issued on 1/10/2015, united states patent number 20140040838 issued on 6/2/2014, and united states patent number 7,260,442 issued on 21/8/2007, each of which is incorporated herein by reference in its entirety.
In some embodiments, an IC device includes: an anti-fuse device including a dielectric layer between the first gate structure and the active region; a first transistor including a second gate structure located over an active region; and a second transistor including a third gate structure located over the active region, wherein the first gate structure is located between the second gate structure and the third gate structure. In some embodiments, the active region includes first to fourth S/D structures, the second gate structure is positioned over the first S/D structure and the second S/D structure, the first gate structure is positioned over the second S/D structure and the third S/D structure, and the third gate structure is positioned over the third S/D structure and the fourth S/D structure. In some embodiments, an IC device includes: a first contact structure configured to electrically connect the active region to a conductor; and a second contact structure configured to electrically connect the active region to the conductor, wherein the first, second, and third gate structures are located between the first and second contact structures. In some embodiments, an IC device includes: a first via structure configured to electrically connect the second gate structure to the conductor; and a second via structure configured to electrically connect the third gate structure to the conductor. In some embodiments, the IC device is configured to conduct current from the first gate structure to the bit line through the first transistor and the second transistor in parallel. In some embodiments, the antifuse device is a first antifuse device, the dielectric layer is a first dielectric layer, and the IC device further comprises a second antifuse device comprising a second dielectric layer located between the fourth gate structure and the active region; a third transistor including a fifth gate structure located over the active region; and a fourth transistor including a sixth gate structure located over the active region, wherein the fourth gate structure is located between the fifth gate structure and the sixth gate structure. In some embodiments, the active region includes first to seventh S/D structures, the second gate structure is located over the first and second S/D structures, the first gate structure is located over the second and third S/D structures, and the third gate structure is located over the third and fourth S/D structures, the fifth gate structure is located over the fourth and fifth S/D structures, the fourth gate structure is located over the fifth and sixth S/D structures, and the sixth gate structure is located over the sixth and seventh S/D structures. In some embodiments, the IC device further comprises: a first contact structure configured to electrically connect the active region to a conductor; a second contact structure configured to electrically connect the active region to a conductor; and a third contact structure configured to electrically connect the active region to the conductor, wherein the first, second, and third gate structures are located between the first and second contact structures, and the fourth, fifth, and sixth gate structures are located between the second and third contact structures.
In some embodiments, a circuit includes a conductive line, a bit line, an antifuse device, a first transistor, and a second transistor, wherein the antifuse device and the first transistor are coupled in series between the conductive line and the bit line, and the antifuse device and the second transistor are coupled in series between the conductive line and the bit line. In some embodiments, the first transistor is coupled to a first terminal of the antifuse device, and the second transistor is coupled to a second terminal of the antifuse device. In some embodiments, each of the first transistor and the second transistor is coupled between the antifuse device and the bit line. In some embodiments, the gate of the first transistor is coupled to the gate of the second transistor. In some embodiments, each of the antifuse device, the first transistor, and the second transistor comprises an NMOS transistor. In some embodiments, the conductive line, the bit line, the antifuse device, the first transistor, and the second transistor are included in an antifuse cell of the antifuse cell array. In some embodiments, the conductive line is a first conductive line, the antifuse device is a first antifuse device, and the circuit further includes a second conductive line, a second antifuse device, a third transistor, and a fourth transistor, wherein the second antifuse device and the third transistor are coupled in series between the second conductive line and the bit line, and the second antifuse device and the fourth transistor are coupled in series between the second conductive line and the bit line.
In some embodiments, a method of operating a circuit includes receiving a voltage at a gate of an antifuse device, and coupling the antifuse device to a bit line using a first transistor and a second transistor simultaneously. In some embodiments, coupling the antifuse device to the bit line includes applying an electric field to a dielectric layer of the antifuse device, the electric field having a symmetry based on the first transistor and the second transistor. In some embodiments, coupling the antifuse device to the bit line includes programming the antifuse device by breaking down a dielectric layer between the gate and a portion of the substrate located between the first transistor and the second transistor. In some embodiments, coupling the antifuse device to the bit line includes generating a current in the bit line, the current including a first component flowing through the first transistor in a first direction and a second component flowing through the second transistor in a second direction opposite the first direction. In some embodiments, using the first transistor and the second transistor simultaneously includes receiving a same signal at a gate of the first transistor and a gate of the second transistor.
The foregoing outlines features of several embodiments so that those skilled in the art may better understand the aspects of the present disclosure. Those skilled in the art should appreciate that they may readily use the present disclosure as a basis for designing or modifying other processes and structures for carrying out the same purposes and/or achieving the same advantages of the embodiments introduced herein. Those skilled in the art should also realize that such equivalent constructions do not depart from the spirit and scope of the present disclosure, and that they may make various changes, substitutions, and alterations herein without departing from the spirit and scope of the present disclosure.