阅读说明：本技术 Euv产生装置
(EUV generating device
) 是由 田炳焕 于 2019-02-13 设计创作，主要内容包括：极紫外(EUV)产生装置，包括：壳体模块，其包括：壳体，其内部维持真空状态；以及出射窗，其形成在壳体一侧；激光源，其通过出射窗向壳体的内部发射激光，等离子体产生模块，其位于壳体内部并通过允许朝向流入激光焦点区域的等离子气体发射激光来产生等离子体，以及射频(RF)电源模块，其在等离子气体流入激光焦点区域之前，对等离子气体预电离。(An Extreme Ultraviolet (EUV) generating device, comprising: a housing module, comprising: a housing, the interior of which is maintained in a vacuum state; and an exit window formed at one side of the housing; the plasma generation apparatus includes a laser source emitting laser light to an inside of a housing through an exit window, a plasma generation module located inside the housing and generating plasma by allowing the laser light to be emitted toward plasma gas flowing into a laser focal region, and a Radio Frequency (RF) power supply module pre-ionizing the plasma gas before the plasma gas flows into the laser focal region.)
1. An extreme ultraviolet generating device comprising:
a housing including a case configured to be connected to a vacuum pump such that an inside of the case can be maintained in a vacuum state, and a window formed at one side of the case;
a laser source configured to emit laser light through the window toward an interior of the housing;
a plasma generating device located inside the housing, the plasma generating device configured to generate plasma in response to emitting laser light toward a plasma gas flowing into a laser focal region; and
a radio frequency power supply device configured to pre-ionize the plasma gas prior to flowing into the laser focal region.
2. The extreme ultraviolet generating apparatus according to claim 1,
the plasma generation device includes:
a laser path tube having a first end, a second end, and a central axis that coincides with an emission path of laser light emitted into the laser path tube from the first end of the laser path tube such that the laser focal region is closer to the second end of the laser path tube than the first end of the laser path tube; and
a gas supply pipe connected to the laser path pipe, the gas supply pipe being configured to supply the plasma gas to an inside of the laser path pipe, and
the radio frequency power supply device includes:
a radio frequency coil wound on one or more of an outer circumferential surface of the gas supply tube and an outer circumferential surface of the laser path tube downstream of a junction of the gas supply tube and the laser path tube, and
a radio frequency power source configured to supply power to the radio frequency coil.
3. The euv generating apparatus according to claim 2, wherein the plasma generating apparatus further comprises:
a gas focusing tube having a first end connected to a second end of the laser pathtube, the gas focusing tube being shaped such that an inner diameter of the gas focusing tube decreases from the first end thereof toward the second end thereof, and wherein
The laser focal region is closer to the second end of the gas focusing tube than the first end of the gas focusing tube.
4. The euv generating device of claim 3, wherein the laser path tube has an inner diameter smaller than an inner diameter of the gas supply tube and larger than an inner diameter of the second end of the gas focusing tube.
5. The euv generating apparatus according to claim 2, further comprising:
an electromagnet comprising an annularly wound coil, the central axis of the electromagnet coinciding with the central axis of the laser path tube, wherein
The laser focus area is located on a central axis of the electromagnet.
6. The euv generating apparatus according to claim 5, wherein the plasma generating apparatus further comprises:
a gas focusing tube having a first end connected to a second end of the laser path tube, the gas focusing tube being shaped such that an inner diameter of the gas focusing tube decreases from the first end to the second end thereof; and
a gas introduction tube connected to a second end of the gas focusing tube and extending toward an interior of the electromagnet.
7. The euv generating apparatus according to claim 2, further comprising:
a concentrator downstream of the laser path tube, the concentrator having a semi-ellipsoidal shape including a laser entrance aperture such that the extreme ultraviolet generating device is configured to deliver the plasma gas from the laser path tube to the concentrator via the laser entrance aperture, wherein
The laser focal region is the region of the concentrator that includes the first focal point of the semi-ellipsoid.
8. The euv generating apparatus according to claim 7, further comprising:
an electromagnet including an annularly wound coil, a central axis of the electromagnet coinciding with a central axis of the laser path tube, the electromagnet being located outside the condenser such that the electromagnet surrounds the first focus, and the laser focus area is located on the central axis of the electromagnet.
9. The euv generating device according to claim 8, wherein the electromagnet has a ring shape such that both ends of the electromagnet have the same inner diameter.
10. The euv generating device according to claim 8, wherein the electromagnet has an inner circumferential surface having a shape corresponding to the shape of the outer circumferential surface of the condenser.
11. The euv generating apparatus according to claim 2, further comprising:
a condenser located downstream of the laser path tube, the condenser having a shape of a semi-ellipsoid including a laser incident hole such that the extreme ultraviolet generating device is configured to transmit the plasma gas from the laser path tube to the condenser via the laser incident hole, the laser incident hole being located at a point on the semi-ellipsoid where a line parallel to a cross section of the semi-ellipsoid and passing through a first focal point of the semi-ellipsoid intersects an inner circumferential surface of the semi-ellipsoid, wherein
The laser focal region is located in a region of the concentrator that includes the first focal point.
12. The euv generating device according to claim 1, wherein the plasma generating device is configured to generate euv radiation by a laser-generated plasma method such that the euv radiation generated thereby has a wavelength between 10nm and 20 nm.
13. An extreme ultraviolet generating apparatus configured to generate extreme ultraviolet rays by using a laser-generated plasma method, the extreme ultraviolet generating apparatus comprising:
a plasma generating device configured to pre-ionize a plasma gas to generate a pre-ionized plasma gas, and generate a plasma by emitting laser light toward the pre-ionized plasma gas.
14. The euv generating apparatus according to claim 13, wherein the plasma generating apparatus comprises:
a laser path tube having a first end and a second end, the laser path tube configured to direct a plasma gas to a laser focus region, the laser focus region being closer to the second end than the first end of the laser path tube; and
a gas supply pipe connected to the laser path pipe, the gas supply pipe configured to supply the plasma gas to an inside of the laser path pipe.
15. The euv generating device according to claim 14, further comprising:
a radio frequency power supply device configured to pre-ionize the plasma gas, the radio frequency power supply device comprising:
a radio frequency coil wound on one or more of an outer circumferential surface of the gas supply tube and an outer circumferential surface of the laser path tube downstream of a junction of the gas supply tube and the laser path tube; and
a radio frequency power source configured to supply power to the radio frequency coil.
16. The euv generating device according to claim 14, further comprising:
an electromagnet comprising an annularly wound coil, the central axis of the electromagnet coinciding with the central axis of the laser path tube, wherein
The laser focus area is located on a central axis of the electromagnet.
17. The euv generating device according to claim 14, further comprising:
a condenser located downstream of the laser path tube, the condenser having a shape of a semi-ellipsoid including a laser incident hole such that the extreme ultraviolet generating device is configured to transmit the plasma gas from the laser path tube to the condenser via the laser incident hole, the laser incident hole being located at a point on the semi-ellipsoid where a line parallel to a cross section of the semi-ellipsoid and passing through a first focal point of the semi-ellipsoid intersects an inner circumferential surface of the semi-ellipsoid, wherein
The laser focal region is located in a region of the concentrator that includes the first focal point.
18. An extreme ultraviolet generating device comprising:
a laser source configured to emit laser light to a laser focal region;
a plasma generating device configured to generate plasma by introducing a plasma gas into the laser focal region;
a radio frequency power supply device configured to pre-ionize the plasma gas to produce a pre-ionized plasma gas prior to the plasma gas flowing into the laser focus region; and
an electromagnet configured to focus the pre-ionized plasma gas to the laser focal region.
19. The euv generating apparatus according to claim 18, wherein the plasma generating apparatus comprises:
a laser path pipe whose central axis coincides with an emission path of the laser light, and into which the plasma gas flows;
a gas supply pipe connected to the laser path pipe, the gas supply pipe configured to supply the plasma gas to an inside of the laser path pipe; and
a gas focusing tube having a first end connected to the laser path tube, the gas focusing tube being shaped such that its inner diameter decreases from its first end toward its second end, wherein
The laser focal region is closer to the second end of the gas focusing tube than the first end of the gas focusing tube, and
the electromagnet is located outside of the gas focusing tube such that the electromagnet surrounds the gas focusing tube.
20. The euv generating device according to claim 19, wherein the rf power supply device comprises:
a radio frequency coil wound on one or more of an outer circumferential surface of the gas supply tube and an outer circumferential surface of the laser path tube downstream of a junction of the gas supply tube and the laser path tube; and
a radio frequency power source configured to supply power to the radio frequency coil.
Technical Field
Example embodiments of the inventive concepts relate to Extreme Ultraviolet (EUV) generating devices having improved luminous efficiency.
Background
An Extreme Ultraviolet (EUV) generating device is a device that generates plasma using a laser and then generates and supplies EUV rays using the generated plasma. The EUV generating device generates plasma by focusing a laser on a flow path through which plasma gas flows and emitting laser light toward the plasma gas.
Meanwhile, as the size of a pattern on a semiconductor substrate is reduced, semiconductor processes such as a photolithography process require light having a shorter wavelength than general Ultraviolet (UV) rays. Since EUV rays have a shorter wavelength than UV rays, they are applied to an exposure process or an inspection process of a photolithography process. However, when the EUV generating apparatus generates plasma using laser light, since the energy intensity of the generated plasma gas may be low, the intensity of EUV rays generated thereby may be insufficient for an exposure process or an inspection process.
Disclosure of Invention
Example embodiments of the inventive concepts relate to providing an Extreme Ultraviolet (EUV) generating device that improves output intensity and emission efficiency of EUV rays.
According to an example embodiment, there is provided an extreme ultraviolet generating apparatus including: a housing including a case configured to be connected to a vacuum pump such that an inside of the case can be maintained in a vacuum state, and a window formed at one side of the case; a laser source configured to emit laser light through the window toward an interior of the housing; a plasma generating device located inside the housing, the plasma generating device configured to generate plasma in response to emitting laser light toward a plasma gas flowing into a laser focal region; and a Radio Frequency (RF) power supply device configured to pre-ionize the plasma gas before flowing into the laser focal region.
According to an example embodiment, there is provided an extreme ultraviolet generating apparatus configured to generate extreme ultraviolet rays by using a laser generated plasma method, the extreme ultraviolet generating apparatus including: a plasma generating device configured to pre-ionize a plasma gas to generate a pre-ionized plasma gas, and generate a plasma by emitting laser light toward the pre-ionized plasma gas.
According to an example embodiment, there is provided an extreme ultraviolet generating apparatus including: a laser source configured to emit laser light to a laser focal region; a plasma generating device configured to generate plasma by introducing a plasma gas into the laser focal region; a Radio Frequency (RF) power supply device configured to pre-ionize the plasma gas to produce a pre-ionized plasma gas prior to the plasma gas flowing into the laser focus region; and an electromagnet configured to focus the pre-ionized plasma gas to the laser focal region.
Drawings
The above and other objects, features and advantages of the present inventive concept will become more apparent to those skilled in the art by describing in detail some exemplary embodiments thereof with reference to the attached drawings, in which:
fig. 1A and 1B are schematic configuration diagrams illustrating an EUV generating apparatus according to an exemplary embodiment of the inventive concept.
Fig. 2 is a configuration diagram of an EUV generating apparatus according to another exemplary embodiment of the inventive concept.
Fig. 3 is a configuration diagram of an EUV generating apparatus according to another exemplary embodiment of the inventive concept.
Fig. 4 is a configuration diagram of an EUV generating apparatus according to another example embodiment of the inventive concept.
Fig. 5 is a configuration diagram of an EUV generating apparatus according to another example embodiment of the inventive concept.
Fig. 6 is a configuration diagram of an EUV generating apparatus according to another example embodiment of the inventive concept.
Fig. 7 is a configuration diagram of an EUV generating apparatus according to another example embodiment of the inventive concept.
Detailed Description
Hereinafter, an Extreme Ultraviolet (EUV) generating device according to an example embodiment of the inventive concept will be described.
Fig. 1A and 1B are schematic configuration diagrams illustrating an EUV generating apparatus according to an exemplary embodiment of the inventive concept.
Referring to fig. 1A and 1B, an EUV generating apparatus 100 according to an example embodiment of the inventive concept may include a case module 110, a laser source 120, a plasma generating module 130, and a Radio Frequency (RF) power supply module 140. In addition, the EUV generating apparatus 100 may further include a vacuum pump 180 and a gas source 190. Meanwhile, although not shown in detail, the EUV generating apparatus 100 may further include a condensing module (not shown) for condensing the generated EUV rays and a filter module (not shown) for selecting only a desired wavelength of the generated EUV rays.
The EUV generating apparatus 100 is an apparatus that emits laser light to a plasma gas to generate plasma, and then generates and supplies EUV rays using the generated plasma. The EUV generating apparatus 100 may generate EUV rays by using a Laser Produced Plasma (LPP) method. EUV radiation may have a wavelength of 10nm to 0 nm. EUV radiation may have a wavelength of 10nm to 20 nm. The EUV radiation may have a wavelength of 13.5 nm.
As described below, in one or more example embodiments, the EUV generating device 100 may generate plasma by pre-ionizing a plasma gas by applying energy to the plasma gas prior to lasing. That is, the EUV generating apparatus 100 may change the plasma gas into a pre-ionized state by applying an electric field using an inductively coupled induction current, and then generate plasma by emitting laser light to the pre-ionized plasma gas. Here, the pre-ionization state may refer to a state in which the plasma gas is partially or completely ionized, i.e., a state in which energy is lower than energy required to generate plasma. Also, the pre-ionization state may include a state in which the plasma gas is preheated.
Accordingly, since the EUV generating apparatus 100 generates plasma by emitting laser light to the plasma gas in a pre-ionization state formed using an electric field caused by an induced current in one or more exemplary embodiments, EUV rays may be more efficiently generated. That is, the EUV generating apparatus 100 may increase the output intensity and emission efficiency of EUV rays.
The EUV generating apparatus 100 may be applied to various apparatuses that perform semiconductor processes, such as a photolithography process. For example, the EUV generating apparatus 100 may be used for an exposure apparatus that performs an exposure process. In this case, the EUV generating apparatus 100 may supply EUV rays as an exposure beam for performing an exposure process. Also, the EUV generating apparatus 100 may be used as an inspection apparatus for inspecting a reticle.
The housing module 110 may comprise a housing 111, an entrance window 112 and an exit window 113. Although not shown in the drawings, the housing module 110 may further include a vacuum gauge measuring the degree of vacuum inside the housing 111.
The housing 111 is formed in a box shape with a hollow inside. The case 111 provides a space to accommodate the plasma generation module 130. The case 111 provides an internal space where EUV rays are generated. The case 111 may be formed of a material having heat resistance and corrosion resistance, such as stainless steel. Since the case 111 is exposed to plasma at a high temperature, the case 111 may be formed of a material that is not damaged by plasma at a high temperature.
The housing 111 may maintain a vacuum therein. The case 111 may maintain a suitable vacuum degree to prevent the laser or EUV radiation from being absorbed into the atmosphere during the formation of the EUV radiation. For example, the housing 111 may hold 10-3Torr or lower vacuum. Also, the housing 111 has an exterior that is in contact with the atmosphere, and may be combined with an optical vacuum chamber (not shown) at the exit window 113. Here, the optical vacuum chamber may be a reticle inspection chamber using the generated EUV radiation. Also, the housing 111 may be located in another vacuum chamber.
The entrance window 112 may be formed on one side of the case 111. The entrance window 112 may be provided with a path through which the laser light passes. Also, the entrance window 112 may perform a function of separating the housing 111 from the external environment. For example, when the housing 111 is located in the atmosphere, the entrance window 112 separates the inner space of the housing 111 from the outside so as to maintain a vacuum state within the housing 111. The entrance window 112 may be formed of a material that reduces (or, alternatively, minimizes) the loss of incident laser light. The entrance window 112 may be formed of quartz, and may separate the inside from the outside of the case 111 to pass laser light therethrough. Meanwhile, when the outside of the case 111 is in a vacuum state, the entrance window 112 may be omitted. In this case, the entrance window 112 may be formed as a hollow hole.
The exit window 113 may be formed at the other side of the housing 111. The exit window 113 may be provided with a path through which EUV radiation passes. When the housing 111 is connected to an additional optical treatment chamber (not shown) through the exit window 113, the exit window 113 may be formed as a hollow hole. Also, the exit window 113 may be formed as a filter that passes only EUV rays and blocks laser light. The exit window 113 may be formed as a filter comprising zirconium. Moreover, the exit window 113 may perform the function of separating the housing 111 from the external environment. For example, when the housing 111 is located in the atmosphere, the exit window 113 separates the inner space of the housing 111 from the outside so as to maintain a vacuum state within the housing 111. The exit window 113 may be formed of a material that reduces (or alternatively minimizes) the loss of EUV radiation emitted therefrom. The entrance window 112 and the exit window 113 may be installed at various positions in the housing 111 according to the positions of the plasma generation module 130, the RF power supply module 140, or other components in the housing 111.
A vacuum pump may be connected to the housing 111 and may maintain a vacuum within the housing 111. The vacuum pump may include various vacuum pumps sufficient to maintain, for example, 10 within the housing 111-3The vacuum of the tray.
The laser source 120 is a light source that outputs laser light. The laser source 120 may be located outside the housing 111, and may emit laser light toward the entrance window 112. The laser source 120 may output laser light having energy sufficient to bring the plasma gas into a plasma state. The laser emitted by the laser source 120 may form a focus in a laser focus region (labeled as "a") in the plasma generation module 130 and may effectively heat the plasma gas. As discussed in more detail below, since the plasma gas is pre-ionized by the RF power module 140, the plasma may be generated more efficiently than when a laser is emitted to the plasma gas. The laser source 120 may have high intensity pulses. The laser source 120 may be CO2A laser, an NdYAG laser, or a titanium sapphire laser. Further, the laser source 120 may be an ArF excimer laser or a KrF excimer laser.
The laser source 120 may further include a focusing lens 121. The focusing lens 121 may be located between the laser source 120 and the housing 111. The focusing lens 121 may adjust a focal length of the laser light emitted by the laser light source 120. As the focusing lens 121, a conventional focusing lens may be used.
The plasma generation module 130 may include a laser path tube 131 and a gas supply tube 132. The plasma generation module 130 may further include a gas focusing tube 133. The plasma generation module 130 forms plasma by using laser and plasma gas and generates EUV rays. In more detail, the plasma generation module 130 may be located in the housing 111, and may generate plasma by emitting laser light toward the plasma gas flowing into the laser focus region "a".
The laser path tube 131 may be formed to have a tube shape including a hollow and open side and other sides. The laser path tube 131 may be formed as a tube having an inner diameter of a first diameter D1. The laser path tube 131 may be located in the housing 111 such that the central axis coincides with the center of the entrance window 112. The laser path tube 131 may be located in the housing 111 such that the central axis coincides with the emission path. The laser may be incident on one side of the laser path tube 131 and may be emitted from the other side. In the laser path tube 131, since the laser light is emitted along the central axis, a laser focal region "a" may be formed at a position on the central axis. That is, in the laser path tube 131, since the emission direction of the laser light is equal to the flow direction of the plasma gas supplied by the gas supply tube 132, the laser focal region "a" can be easily formed in a desired region. For example, a laser focal region "a" where the laser light is condensed may be formed in the laser path tube 131. The laser focal region "a" may be formed inside or outside the other side of the laser path tube 131. Further, a laser focal region "a" may be formed at a position where the gas supply pipe 132 is combined with the laser path pipe 131.
The laser path tube 131 may be formed as a dielectric. The laser path tube 131 may be formed of a transparent material such as quartz. Also, the laser path tube 131 may be formed of alumina or a ceramic material such as zirconia.
The laser path tube 131 may be maintained in a vacuum state to reduce (or alternatively, prevent) loss caused by laser light scattering and efficiently form plasma. The laser path tube 131 may be located inside the housing 111 so as to maintain a vacuum state inside thereof. Also, although not shown in detail in the drawings, the air in the laser path tube 131 may be discharged through an additional discharge tube so that a vacuum state of the inside thereof may be maintained.
A mirror (not shown) reflecting or condensing the generated EUV ray may be further included between the other side of the laser path tube 131 and the exit window 113. In this case, the central axis of the laser path tube 131 may not coincide with the center of the exit window 113.
The gas supply pipe 132 may be formed to have a pipe shape including a hollow and open top side and a bottom side. The gas supply pipe 132 may be formed such that the inner diameter is the second diameter D2. The gas supply tube 132 may be formed of the same material as that of the laser path tube 131. The gas supply pipe 132 may be combined with the laser path pipe 131 to be perpendicular or inclined thereto. That is, the gas supply pipe 132 may be combined such that its central axis is perpendicular to the central axis of the laser path pipe 131 or intersects at an inclination angle. The top of the gas supply pipe 132 may be combined with the laser path pipe 131 while passing from the outer circumferential surface to the inner circumferential surface of the laser path pipe 131. The interior of the gas supply tube 132 may be combined with the interior of the laser path tube 132. The gas supply pipe 132 may be coupled with the laser path pipe 131 at an intermediate position in the longitudinal direction based on the laser path pipe 131. When the laser focal region "a" is formed at the other end of the laser path tube 131, the gas supply tube 132 may be combined with the laser path tube 131 while being inclined toward the other end. That is, the gas supply pipe 132 may be coupled with the laser path pipe 131 while the bottom side is rotated around the top side, and coupled with the laser path pipe 131 toward one side of the laser path pipe 131. In this case, the plasma gas supplied from the gas supply tube 132 can more efficiently flow to the other side of the laser path tube 131.
The gas supply pipe 132 may supply plasma gas to the inside of the laser path pipe 131. The second diameter of the gas supply pipe 132 may be larger than the first diameter of the laser path pipe 131. The second diameter may be 1.1 to 2.0 times the first diameter. Therefore, the amount of plasma gas supplied by the gas supply pipe 132 is larger than the amount of gas flowing in the laser path pipe 131. In addition, the plasma gas may flow through the laser path tube 131 at a uniform density.
The gas focusing tube 133 may have a tube shape that is open from the first side to the second side, and has an inner diameter that decreases from the first side to the second side. The gas focusing tube 133 may be integrally formed with the laser path tube 131. The second end of the gas focusing tube 133 may have an inner diameter smaller than the inner diameter of the gas supply tube 132. A first end of the gas focusing tube 133 may be combined with the other end of the laser path tube 131. The gas focusing tube 133 focuses the plasma gas flowing in from the laser path tube 131 while allowing the plasma gas to flow from side to side. That is, the gas focusing tube 133 may increase the density of the plasma gas flowing therein. Since the inner diameter of the second end of the gas focusing tube 133 is formed smaller than that of the laser path tube 131, the plasma gas can be more effectively focused. When the gas focusing tube 133 is formed, the laser focal area "a" may be formed inside or outside the gas focusing tube 133, not inside the laser path tube 131. The laser focus area "a" may be formed inside or outside the second end of the gas focusing tube 133. The gas focusing tube 133 may improve the efficiency of forming plasma by increasing the density of plasma gas in the laser focal region "a". Meanwhile, when the plasma gas can be focused since the inner diameter of the laser path tube 131 is sufficiently small, the gas focusing tube 133 may be omitted.
The RF power supply module 140 may include an RF coil 141 and an RF power supply 142. The RF power module 140 may pre-ionize the plasma gas before the plasma gas flows into the laser focal region "a".
The RF coil 141 may be wound at least once on the outer circumferential surface of the gas supply pipe 132. The RF coil 141 may be wound a sufficient number of times in order to pre-ionize the plasma gas flowing in the gas supply tube 132 or to provide energy for the generation of plasma. The RF coil 141 may generate an inductive coupling type induction current, and may apply an electric field to the plasma gas.
The RF power supply 142 may be electrically connected to the RF coil 141. The RF power supply 142 may provide power for pre-ionizing the plasma gas to the RF coil 141. The RF power source 142 may provide power at a frequency of, for example, 13.5MHz to 80 MHz.
The vacuum pump 180 may be connected to the housing 111 and may maintain a vacuum within the housing 111. The vacuum pump 180 may be connected to the laser path tube 131 and may maintain a vacuum within the laser path tube 131. Depending on the required degree of vacuum, a suitable vacuum pump may be used.
The gas source 190 may be connected to the gas supply tube 132, and may supply plasma gas to the gas supply tube 132. Ne, He, Ar, or Xe gas may be used as the plasma gas.
As shown in fig. 1A, in some exemplary embodiments, the RF coil 141 may be wound on the outer circumferential surface of the gas supply tube 132. However, as discussed below with reference to fig. 1B through 7, example embodiments are not limited thereto.
Referring to fig. 1B, in an EUV generating apparatus 200 according to another exemplary embodiment of the inventive concept, an RF coil 241 of an RF power supply module 240 may be wound at the other side of a laser path tube 131. That is, the RF coil 241 may be wound on the outer circumferential surface of the laser path tube 131 between the other end of the laser path tube 131 and the gas focusing tube 133. RF coil 241 may pre-ionize plasma gas at a location near laser focal region "a". Accordingly, the EUV generating apparatus 200 may form plasma more efficiently, thereby improving light emitting efficiency.
Further, in the EUV generating device 200, although not shown in detail in the drawing, the RF coil 141 may be wound even at the same position as that in fig. 1A.
Hereinafter, EUV generating devices according to other example embodiments of the inventive concept will be described.
Fig. 2 is a configuration diagram of an EUV generating apparatus according to another exemplary embodiment of the inventive concept.
Referring to fig. 2, an EUV generating apparatus 300 according to another example embodiment of the inventive concept may include a case module 110, a laser source 120, a plasma generating module 130, an RF power module 240, and an electromagnet 350.
In contrast to the EUV generating devices 100 and 200 shown in fig. 1A and 1B, the EUV generating device 300 may be formed identically or similarly, except that an electromagnet 350 is also included therein. Therefore, hereinafter, the electromagnet 350 of the EUV generating device 300 will be mainly described. Further, in describing the EUV generating apparatus 300, the same reference numerals are used to designate the same or similar components as those of the EUV generating apparatuses 100 and 200 illustrated in fig. 1A and 1B, and detailed descriptions thereof will be omitted. Meanwhile, the same is true in other exemplary embodiments below.
The electromagnet 350 may have a ring shape formed by winding a coil. Although not shown in detail, the electromagnet 350 may include an annular housing, an annular magnetic core positioned in the housing, and a coil wound around the magnetic core. The coil may be annularly wound on the core. The inner diameter of the electromagnet 350 may correspond to or be larger than the outer diameter of the laser path tube 131. The electromagnet 350 may have a length sufficient to focus the plasma gas. The length of the electromagnet 350 may be determined empirically. The electromagnet 350 may be positioned such that one side thereof contacts or partially overlaps the other side of the laser path tube 131.
The electromagnet 350 may be positioned such that its central axis coincides with the central axis of the laser path tube 131. The laser focal region "a" may be located at the central axis of the electromagnet 350. The electromagnet 350 may receive power from another external power source (not shown) and may generate a magnetic field. However, example embodiments are not limited thereto, and the electromagnet 350 may share a power supply with other components of the EUV generating device 300. The electromagnet 350 may apply a magnetic force to a region including the laser focal region "a". That is, the electromagnet 350 may apply a magnetic force to the plasma gas flowing into the laser focal region "a". The electromagnet 350 may focus the pre-ionized plasma gas flowing from the other side of the laser path tube 131 in a region including the laser focal region "a" by using a magnetic force. That is, the electromagnet 350 may increase the density of the plasma gas in the region including the laser focal region "a". Since the plasma gas becomes an ionized state in the laser path tube 131 or the gas supply tube 132, the plasma gas can be focused by the magnetic force of the magnetic field.
When the gas focusing tube 133 is combined with the other side of the laser path tube 131, the electromagnet 350 may be positioned to surround at least the outer circumferential surface of the gas focusing tube 133. The electromagnet 350 may have a length longer than that of the gas focusing tube 133 and may be combined to surround an area including the outer circumferential surface of the gas focusing tube 133. Further, the inner diameter of the electromagnet 350 may correspond to the inner diameter of the gas focusing tube 133. Accordingly, one side of the electromagnet 350 may be in contact with and coupled to the second end of the gas focusing tube 133. The laser focus area "a" may be formed inside the gas focusing tube 133 or the electromagnet 350.
Hereinafter, an EUV generating apparatus according to another exemplary embodiment of the inventive concept will be described.
Fig. 3 is a configuration diagram of an EUV generating apparatus according to another exemplary embodiment of the inventive concept.
Referring to fig. 3, an EUV generating apparatus 400 according to another example embodiment of the inventive concept may include a case module 110, a laser source 120, a plasma generating module 430, an RF power module 240, and an electromagnet 350.
The plasma generation module 430 may include a laser path tube 131, a gas supply tube 132, a gas focusing tube 133, and a gas introduction tube 434.
The gas introduction pipe 434 may have an inner diameter corresponding to that of the second end of the gas focusing pipe 133. The gas introduction pipe 434 may be integrally formed with the laser path pipe 131 and the gas focusing pipe 133. The outer diameter of the gas introduction pipe 434 may correspond to the inner diameter of the electromagnet 350. The gas introduction pipe 434 may have a length corresponding to at least the length of the electromagnet 350. One side of the gas introduction pipe 434 may be combined with the second end of the gas focusing pipe 133 and may extend toward the inside of the electromagnet 350. The gas introduction pipe 434 may guide the plasma gas flowing in from the gas focusing pipe 133 to flow into the inside of the electromagnet 350.
Since the inner circumferential surface of the electromagnet 350 is in contact with or adjacent to the outer circumferential surface of the gas introduction pipe 434, the distance between the electromagnet 350 and the plasma gas can be reduced. Accordingly, the electromagnet 350 may more effectively focus the plasma gas by increasing the magnetic force toward the plasma gas.
Hereinafter, an EUV generating apparatus according to another exemplary embodiment of the inventive concept will be described.
Fig. 4 is a configuration diagram of an EUV generating apparatus according to another example embodiment of the inventive concept.
Referring to fig. 4, an EUV generating apparatus 500 according to another example embodiment of the inventive concept may include a case module 110, a laser source 120, a plasma generating module 130, an RF power module 240, and a condensing module 560.
The converging module 560 may include a laser entrance aperture 561 and an EUV exit aperture 562. In addition, the convergence module 560 may further include a mirror 563. Meanwhile, the convergence module 560 may further include a filter (not shown) filtering the focused EUV rays and an optical device (not shown) for changing a path of the EUV rays. Since the convergence module 560 focuses and emits EUV rays generated from the plasma, efficiency of supplying EUV rays may be improved.
The convergence module 560 may be formed to have a semi-ellipsoidal shape formed by cutting an ellipsoid along a cross section 560a perpendicular to the central axis. Here, the central axis may be an axis connecting the first focus f1 of the ellipsoid to the second focus f 2. Also, the first focus f1 may be a focus located on one side of an ellipse that is formed when the ellipsoid forming the convergence module 560 is cut in the major axis direction. The second focus f2 may be a focus located on the other side of the ellipse. The semi-ellipsoid may include a first focus point f1 on one side and a virtual second focus point f2 on the other side. Also, the cross section 560a may be a surface located at an intermediate position of the central axis or a surface at a position spaced apart from the intermediate position. Also, the convergence module 560 may be formed as an elliptical mirror or an elliptical mirror. The convergence module 560 may be formed of a transparent material. For example, the convergence module 560 may be formed of a quartz material. Also, the condensing module 560 may include a Mo — Si multi-layered film formed on an inner reflective surface to effectively reflect EUV rays. Here, the Mo — Si multilayer film may be a film formed by alternately laminating Mo layers and SiC layers.
The laser incident hole 561 may be formed at the center of the inner circumferential surface of the semi-ellipsoid. That is, the laser incident hole 561 may be formed at a point where a line connecting the center of the cross-section to the first focus f1 of the ellipse intersects the inner circumferential surface of the semi-ellipsoid. The laser incident hole 561 may be formed to have a sufficient diameter required to allow the laser light to pass therethrough. The laser incident hole 561 may be formed as a hole formed in a conventional mirror. The EUV exit hole 562 may be formed on the opposite side to the laser entrance hole 561. The EUV exit hole 562 may be formed at a position of the semi-ellipsoid that is open due to the cross section. The EUV exit hole 562 may output the generated EUV ray to the outside.
The convergence module 560 may be combined such that the laser incident hole 561 communicates with the laser path tube 131 or the gas focusing tube 133. The laser incident hole 561 may be directly connected to the laser path tube 131 or the gas focusing tube 133. The laser incident hole 561 allows laser light to be emitted toward the inside of the condensing module 560 through the laser path tube 131. The convergence module 560 may include a laser focal region "a" therein. In the convergence module 560, a region including the first focus f1 may be formed as a laser focus region "a". The laser incident hole 561 allows laser light to be emitted toward the laser focal region "a" located inside the condensing module 560. In addition, the laser entrance aperture 561 may allow ionized plasma gas to flow into the convergence module 560.
The plasma gas and the laser may form plasma in the laser focus region "a" of the convergence module 560 and generate EUV rays. EUV radiation generated using a plasma can be emitted in all directions. The convergence module 560 may converge the EUV radiation emitted in various directions and emit the converged EUV radiation in a direction opposite to the laser focus region "a". Here, the EUV radiation emitted by the converging module 560 may pass through a reflection focus located on the opposite side of the central axis of the ellipse from the laser focal region "a". Here, the reflection focal point may be the second focal point f2 of the ellipse. EUV rays condensed by the condensing module 560 may pass through a reflective focus and may be emitted in the opposite direction.
The mirror 563 may be installed at a position near the reflection focal point, and may emit EUV rays in a specific direction. The mirror 563 may allow EUV radiation to exit downwards. Here, the exit window 113 may be located on a bottom surface of the housing 111. As the mirror 563, a conventional mirror for reflecting and condensing EUV rays may be used. Also, the mirror 563 may be formed in a shape capable of effectively reflecting and converging EUV rays. The mirror 563 may be formed as an elliptical mirror or an elliptical mirror. Also, the mirror 563 may include a Mo — Si multilayer film formed on an inner reflective surface to effectively reflect EUV rays.
Hereinafter, an EUV generating apparatus according to another exemplary embodiment of the inventive concept will be described.
Fig. 5 is a configuration diagram of an EUV generating apparatus according to another example embodiment of the inventive concept.
Referring to fig. 5, an EUV generating apparatus 600 according to another example embodiment of the inventive concept may include a case module 110, a laser source 120, a plasma generating module 130, an RF power supply module 240, and a condensing module 660.
The converging module 660 may include a laser incident hole 661 and an EUV exit hole 562. In addition, the convergence module 660 may further include a mirror 563. In addition, the convergence module 660 may further include a laser exit hole 664.
The convergence module 660 may be formed to have a semi-ellipsoidal shape formed by cutting an ellipsoid along a cross section 660a perpendicular to its central axis. The semi-ellipsoid may include a first focus point f1 on one side and a virtual second focus point f2 on the other side. Similar to the convergence module 560 according to the exemplary embodiment shown in fig. 4, the convergence module 660 may be formed of sapphire and may include a Mo — Si multilayer film on a reflective surface.
The laser incident hole 661 may be formed at a point where a line parallel to the cross section and passing through the first focal point f1 intersects the inner circumferential surface of the ellipsoid. That is, the laser incident hole 661 may be formed at a position perpendicular to the central axis of the semi-ellipsoid. The laser incident hole 661 may be formed to have a sufficient diameter required to allow the laser light to pass therethrough. The EUV exit hole 562 may be formed at a position that intersects the laser entrance hole 661 at right angles. That is, the EUV exit hole 562 may be formed at a position of the semi-ellipsoid opened by the cross section. The EUV exit hole 562 may output the generated EUV ray to the outside.
The convergence module 660 may be combined such that the laser incident hole 661 communicates with the laser path tube 131 or the gas focusing tube 133. The laser incident hole 661 may be directly connected to the laser path tube 131 or the gas focusing tube 133. The laser incident hole 661 allows laser light to be emitted toward the inside of the condensing module 660 through the laser path tube 131. The laser incident hole 661 may allow the ionized plasma gas to flow into the convergence module 660.
The convergence module 660 may receive laser light incident in a horizontal direction and emit EUV rays in a downward direction. Therefore, in the converging module 660, the incident direction of the laser light and the exit direction of the EUV ray may intersect at a right angle.
The mirror 563 may reflect the EUV radiation and emit the EUV radiation towards the exit window 113. The mirror 563 may allow the EUV radiation to exit in a horizontal direction. Here, the exit window 113 may be located on a side surface of the housing 111.
The laser exit hole 664 may allow the laser light passing through the laser focal region "a" to be emitted from the convergence module 660. A laser dump (not shown) is installed outside the laser exit hole 664 to convert energy of the laser light emitted therefrom into heat and dissipate the heat.
Fig. 6 is a configuration diagram of an EUV generating apparatus according to another example embodiment of the inventive concept.
Referring to fig. 6, an EUV generating apparatus 700 according to another example embodiment of the inventive concept may include a case module 110, a laser source 120, a plasma generating module 130, an RF power module 240, an electromagnet 750, and a condensing module 560.
The electromagnet 750 may be formed in a ring shape in which one side and the other side have the same inner diameter. The electromagnet 750 may be formed to have an inner diameter larger than an outer diameter of the cross-section of the convergence module 560. The electromagnet 750 may be located outside the convergence module 560 to surround an area including the laser focus area "a". The electromagnet 750 may have a sufficient length for focusing the plasma gas in the laser focal region "a". For example, the electromagnet 750 may be positioned such that one side thereof contacts or partially overlaps the other side of the laser path tube 131 or the gas focusing tube 133. In addition, the other side of the electromagnet 750 may be positioned at the other side of the condensing module 560 instead of the laser focal region "a". Accordingly, the electromagnet 750 may focus the plasma gas flowing into the convergence module 560 through the laser path tube 131 or the gas focusing tube 133 in the laser focus region "a".
Fig. 7 is a configuration diagram of an EUV generating apparatus according to another example embodiment of the inventive concept.
Referring to fig. 7, an EUV generating apparatus 800 according to another example embodiment of the inventive concept may include a case module 110, a laser source 120, a plasma generating module 130, an RF power module 240, an electromagnet 850, and a condensing module 560.
The electromagnet 850 may be formed to have a ring shape, and may have an inner circumferential surface having a shape corresponding to that of the outer circumferential surface of the convergence module 560. That is, the electromagnet 850 may be formed to have a shape in which the inner diameter increases from one side to the other side. The electromagnet 850 may have a sufficient length for focusing the plasma gas in the laser focal region "a". For example, the electromagnet 850 may be positioned such that one side thereof contacts or partially overlaps the other side of the laser path tube 131 or the gas focusing tube 133. In addition, the other side of the electromagnet 850 may be positioned at the other side of the condensing module 560, not the laser focal region "a". Accordingly, since the electromagnet 850 is installed adjacent to the convergence module 560, the plasma gas flowing into the convergence module 560 can be effectively focused.
According to example embodiments of the inventive concept, an EUV generating device that improves output intensity and emission efficiency of EUV rays may be implemented.
According to one or more example embodiments, although not shown, the EUV generating apparatus 100 to 800 may further include a controller (not shown) configured to control the laser source, the vacuum pump, the gas source, the RF power source, and/or the electromagnet such that the EUV generating apparatus 100 to 800 pre-ionizes the plasma gas supplied thereto and generates plasma by emitting laser light to the plasma gas in a pre-ionized state such that the EUV generating apparatus 100 to 800 may increase output intensity and emission efficiency of EUV rays.
In some example embodiments, the controller is implemented using hardware, a combination of hardware and software, or a non-transitory storage medium storing software executable to perform its functions.
Hardware may be implemented using processing circuitry, such as, but not limited to, one or more processors, one or more Central Processing Units (CPUs), one or more controllers, one or more Arithmetic Logic Units (ALUs), one or more Digital Signal Processors (DSPs), one or more microcomputers, one or more Field Programmable Gate Arrays (FPGAs), one or more systems on a chip (SoC), one or more Programmable Logic Units (PLUs), one or more microprocessors, one or more Application Specific Integrated Circuits (ASICs), or any other device or devices capable of responding to and executing instructions in a defined manner.
The software may include a computer program, program code, instructions, or some combination thereof, for instructing or constructing a hardware device to operate as desired, individually or collectively. The computer program and/or program code can include a program or computer-readable instructions, software components, software modules, data files, data structures, etc., that can be implemented by one or more hardware devices, such as the one or more hardware devices mentioned above. Examples of program code include machine code, such as produced by a compiler, and higher level program code, such as executed using an interpreter.
For example, when the hardware device is a computer processing device (e.g., one or more processors, CPUs, controllers, ALUs, DSPs, microcomputers, microprocessors, etc.), the computer processing device may be configured to execute program code by performing arithmetic, logical, and input/output operations according to the program code. Once the program code is loaded into the computer processing apparatus, the computer processing apparatus may be programmed to execute the program code, thereby converting the computer processing apparatus into a special purpose computer processing apparatus. In a more specific example, when the program code is loaded into a processor, the processor becomes programmed to perform the program code and operations corresponding thereto, thereby converting the processor into a specialized processor. In another example, the hardware device may be an integrated circuit that is customized to a specific processing circuit (e.g., ASIC).
A hardware device, such as a computer processing device, may run an Operating System (OS) and one or more software applications running on the OS. The computer processing means may also access, store, manipulate, process and create data in response to execution of the software. For simplicity, one or more example embodiments may be shown as one computer processing device; however, those skilled in the art will appreciate that a hardware device may include multiple processing elements and multiple types of processing elements. For example, a hardware device may include multiple processors or a processor and a controller. In addition, other processing configurations are possible, such as parallel processors.
According to one or more example embodiments, the storage medium may further include one or more storage devices at the units and/or the devices. The one or more storage devices may be a tangible computer-readable storage medium or a non-transitory computer-readable storage medium, such as a Random Access Memory (RAM), a Read Only Memory (ROM), a permanent mass storage device (such as a disk drive), and/or any other similar data storage mechanism capable of storing and recording data. The one or more storage devices may be configured to store computer programs, program code, instructions, or some combination thereof for one or more operating systems and/or for implementing the example embodiments described herein. The computer program, program code, instructions, or some combination thereof, may also be loaded from a separate computer-readable storage medium into one or more storage devices and/or one or more computer processing devices using a drive mechanism. Such separate computer-readable storage media may include a Universal Serial Bus (USB) flash drive, a memory stick, a blu-ray/DVD/CD-ROM drive, a memory card, and/or other similar computer-readable storage media. The computer program, program code, instructions, or some combination thereof, may be loaded from a remote data storage device into one or more storage devices and/or one or more computer processing devices via a network interface rather than via a computer-readable storage medium. In addition, the computer program, program code, instructions, or some combination thereof, may be loaded onto one or more storage devices and/or one or more processors from a remote computing system that is configured to transmit and/or distribute the computer program, program code, instructions, or some combination thereof, over a network. The remote computing system may transmit and/or distribute the computer program, program code, instructions, or some combination thereof, via a wired interface, an air interface, and/or any other similar medium.
One or more hardware devices, storage media, computer programs, program code, instructions, or some combination thereof, may be specially designed and constructed for the purposes of example embodiments, or they may be known devices that are changed and/or modified for the purposes of example embodiments.
Although the exemplary embodiments of the present inventive concept have been described with reference to the accompanying drawings, it will be understood by those skilled in the art that various modifications may be made without departing from the scope of the inventive concept. Accordingly, the above-described exemplary embodiments should be considered in descriptive sense only and not for purposes of limitation.
