阅读说明：本技术 光刻设备以及光刻方法 (Lithographic apparatus and lithographic method ) 是由 张俊霖 张汉龙 傅中其 刘柏村 陈立锐 郑博中 于 2018-08-24 设计创作，主要内容包括：本公开提供一种光刻设备,包括一激发腔、一标的发射器、一主激光发射器、以及一激光真空装置。标的发射器用以朝向激发腔内的一激发区域发射一标的。主激光发射器用以发射一主脉冲激光至激发区域内的标的。激光真空装置用以发射一真空激光至至激发腔内,且以于激发腔内形成一真空通道。激光真空装置发射真空激光之后,标的发射器发射标的通过真空通道进入激发区域。本公开提供的光刻设备可增加主激光发射器击中标的精准度。(The present disclosure provides a lithographic apparatus including an excitation chamber, a target emitter, a main laser emitter, and a laser vacuum. The target emitter is used for emitting a target towards an excitation area in the excitation cavity. The main laser emitter is used for emitting a main pulse laser to a target in the excitation area. The laser vacuum device is used for emitting a vacuum laser to the excitation cavity and forming a vacuum channel in the excitation cavity. After the laser vacuum device emits the vacuum laser, the target emitter emits the target through the vacuum channel into the excitation area. The lithography equipment provided by the disclosure can increase the accuracy of the main laser transmitter in hitting the bid.)

1. A lithographic apparatus, comprising:

an excitation chamber;

a target emitter for emitting a target toward an excitation region within the excitation chamber;

a main laser emitter for emitting a main pulse laser to the target in the excitation area; and

the laser vacuum device is used for emitting a vacuum laser into the excitation cavity and forming a vacuum channel in the excitation cavity;

wherein after the laser vacuum device emits the vacuum laser, the target emitter emits the target through the vacuum channel into the excitation region.

2. The lithographic apparatus of claim 1, wherein the frequency at which the main laser emitter emits the main pulsed laser, the frequency at which the target emitter emits the target, and the frequency at which the laser vacuum emits the vacuum laser are the same.

3. The apparatus of claim 1, further comprising a pre-laser emitter configured to emit a pre-pulse laser to the target within the excitation region, wherein the pre-pulse laser and the main laser emitter sequentially emit the pre-pulse laser and the main pulse laser after the target is emitted by the target emitter.

4. The lithographic apparatus of claim 3, wherein the pre-laser emitter emits the pre-pulsed laser light at the same frequency as the laser vacuum device emits the vacuum laser light.

5. The lithographic apparatus of claim 3, wherein the power of the vacuum laser is less than the power of the pre-pulse laser and the power of the main pulse laser.

6. The lithographic apparatus of claim 1, wherein the target emitter emits the target in a first direction, the laser vacuum emits the vacuum laser substantially in the first direction, and the main laser emitter emits the main pulse laser in a second direction, wherein the first direction is different from the second direction.

7. A lithographic apparatus, comprising:

the laser vacuum device is used for emitting vacuum laser into an excitation cavity approximately along a first direction so as to form a vacuum channel in the excitation cavity; and

a target emitter for emitting a target in the first direction, wherein the target passes through the vacuum channel to an excitation region.

8. A lithographic method, comprising:

emitting a vacuum laser into an excitation cavity through a laser vacuum device so as to form a vacuum channel in the excitation cavity;

after the vacuum laser is emitted, emitting a target through a target emitter, wherein the target is sent to an excitation area through the vacuum channel; and

emitting a main pulse laser to the target in the excitation area through a main laser emitter.

9. The method of claim 8, further comprising emitting a pre-pulse laser to the target within the excitation region via a pre-laser emitter before the main pulse laser irradiates the target within the excitation region, wherein a power of the vacuum laser is less than a power of the pre-pulse laser and a power of the main pulse laser.

10. A lithographic method according to claim 8, wherein the vacuum laser ionizes a gas within the excitation chamber to form the vacuum channel.

Technical Field

The present disclosure relates generally to semiconductor devices and methods, and more particularly to lithographic devices and methods.

Background

Semiconductor devices have been used in a variety of electronic applications, such as personal computers, cellular phones, digital cameras, and other electronic devices. Semiconductor devices are generally manufactured by sequentially depositing materials for insulating or dielectric layers, conductive layers, and semiconductor layers onto a wafer, and patterning various material layers using photolithographic techniques to form circuit elements and devices thereon. Many integrated circuits are typically fabricated on a single wafer, and individual dies on the wafer are singulated between the integrated circuits along a dicing line. For example, the individual dies are typically packaged separately in a multi-chip module or other type of package.

Due to the requirement of miniaturization of the size of semiconductor processes, extreme ultraviolet rays are used in the photolithography equipment as a light source in the exposure process to form a pattern suitable for a semiconductor process of less than 20nm on a photoresist on a wafer.

However, while current lithographic apparatus using extreme ultraviolet light as the light source in the exposure process meet their objectives, many other requirements have not been met. Accordingly, there is a need to provide improved solutions for lithographic apparatus.

Disclosure of Invention

The present disclosure provides a lithographic apparatus including an excitation chamber, a target emitter, a main laser emitter, and a laser vacuum. The target emitter is used for emitting a target towards an excitation area in the excitation cavity. The main laser emitter is used for emitting a main pulse laser to a target in the excitation area. The laser vacuum device is used for emitting a vacuum laser into the excitation cavity and forming a vacuum channel in the excitation cavity. After the laser vacuum device emits the vacuum laser, the target emitter emits the target through the vacuum channel into the excitation area.

The present disclosure provides a lithographic apparatus including a laser vacuum and a target emitter. The laser vacuum device is used for emitting a vacuum laser to an excitation cavity along a first direction approximately so as to form a vacuum channel in the excitation cavity. The target emitter is configured to emit a target in a first direction, wherein the target passes through the vacuum channel to an excitation region.

The disclosure provides a photolithography method, which includes emitting a vacuum laser into an excitation chamber via a laser vacuum device to form a vacuum channel in the excitation chamber; after the vacuum laser is emitted, emitting a target by a target emitter, wherein the target is transmitted to an excitation area through a vacuum channel; and emitting a primary pulse laser to a target within the excitation region via a primary laser emitter.

Drawings

FIG. 1 is a schematic view of a lithographic apparatus according to some embodiments of the present disclosure.

FIG. 2 is a flow chart of steps of a lithographic method according to some embodiments of the present disclosure.

FIG. 3 is a timing diagram of a photolithography method according to some embodiments of the present disclosure.

Fig. 4A and 4B are schematic diagrams of a lithographic apparatus according to some embodiments of the disclosure at an intermediate stage in a lithographic method.

Description of reference numerals:

lithographic apparatus 1

Light source device 10

Exposure chamber 20

Lighting device 30

Mask device 40

Mask base 41

Optical projection device 50

Reflecting mirror 51

Wafer seat 60

Excitation chamber A10

Light path A11

Target emitter A20

Target retriever A30

Ray collector A50

Through hole A51

Pre-laser emitter A60

Main laser emitter A70

Laser supply device A80

Seed laser generator A81

Power amplifier A82

Laser vacuum apparatus A90

Mirror B1

First focus C1

Second focal point C2

First direction D1

Second direction D2

Target E1

Gas G1

Electron G2

Ion G3

Prepulse laser L1

Main pulse laser L2

Vacuum laser L3

Mask M1

Substrate M11

Pattern layer M12

First interval time P1

Second interval time P2

Third interval P3

Seismic wave S1

First time T1

Second time T2

Third time T3

Fourth time T4

Wafer W1

Photoresist layer W11

Excitation zone Z1

Concentration zone Z2

Conveying zone Z3

Vacuum channel Z4

Detailed Description

The following description provides many different embodiments, or examples, for implementing different features of the invention. The particular examples set forth below are intended merely to illustrate the disclosure and are not intended to limit the invention. For example, the description of a structure having a first feature over or on a second feature may include direct contact between the first and second features, or another feature disposed between the first and second features, such that the first and second features are not in direct contact.

The terms first and second, etc. in the description are used for clarity of explanation only and do not correspond to and limit the claims. The terms first feature, second feature, and the like are not intended to be limited to the same or different features.

Spatially relative terms, such as above or below, are used herein for ease of description of one element or feature relative to another element or feature in the figures. Devices that are used or operated in different orientations than those depicted in the figures are included. The shapes, sizes, thicknesses, and angles of inclination in the drawings may not be drawn to scale or simplified for clarity of illustration, but are provided for illustration only.

FIG. 1 is a schematic view of a lithographic apparatus 1 according to some embodiments of the present disclosure. The lithography apparatus 1 is used to perform a lithography process on a wafer W1. The photolithography process may include a photoresist coating process, a soft bake process, an exposure process, a development process, a hard bake process, and other suitable processes.

In the present embodiment, the lithography apparatus 1 may be an exposure apparatus for performing an exposure process on a wafer W1. The lithographic apparatus 1 may comprise a light source device 10, an exposure chamber 20, an illumination device 30, a mask device 40, an optical projection device 50, and a wafer stage 60. The lithographic apparatus 1 may comprise all of the above-described devices, but it is not necessary to include all of them, as long as the purpose of the use of the lithographic apparatus 1 is achieved.

The lithographic apparatus 1 should not be limited to the devices described in this disclosure. The lithographic apparatus 1 may comprise other suitable devices, such as a coating device, a soft bake device, a developing device, and/or a hard bake device, etc., to enable the lithographic apparatus 1 to perform a complete lithographic process on the wafer W1.

The light source device 10 is used for generating light to the illumination device 30. The light may be extreme ultraviolet (EUV light). In the present embodiment, the wavelength range of the extreme ultraviolet light may be defined as a range between 10nm and 120 nm. In some embodiments, the wavelength of the extreme ultraviolet light can be extended to a soft x-ray (soft x-ray) band ranging from 3nm to 20 nm. Therefore, the light source device 10 can be an extreme ultraviolet light source device. However, the light source device 10 should not be limited to generating extreme ultraviolet rays. The light source apparatus 10 may be configured to emit any photon of any wavelength and intensity from excitation at target E1.

The exposure chamber 20 is disposed at one side of the light source device 10. In some embodiments, the illumination device 30, the mask device 40, the optical projection device 50, and the wafer mount 60 may be disposed within the exposure chamber 20. However, because the gas molecules absorb the extreme ultraviolet light, a vacuum may be maintained inside the exposure chamber 20 to prevent loss of the extreme ultraviolet light.

The illumination device 30 is used for guiding the light (extreme ultraviolet) provided by the light source device 10 to a mask M1 disposed on the light source device 10. The illumination device 30 may include one or more optical elements, such as at least one lens, at least one mirror, and/or at least one refractor. The light emitted from the light source device 10 is refracted, reflected, and/or condensed by the illumination device 30 and then directed to the mask M1 or the mask device 40.

The mask device 40 is used to hold a mask (photo mask, or reticle) M1. In some embodiments, the mask device 40 may be used to move the mask M1 so that light emitted by the illumination device 30 is directed to different areas of the mask M1. In some embodiments, the mask device 40 may include a mask holder 41 for holding the mask M1. The mask base 41 may be an electrostatic (e-chuck) base.

In some embodiments, mask M1 may be a reflective mask M1. In one example, mask M1 may include a substrate M11. The material of the substrate M11 may be Low Thermal Expansion Material (LTEM) or fused quartz (fused quartz). In some embodiments, the low thermal expansion material comprises doped SiO₂Of TiO 2₂Or other suitable materials having low thermal expansion properties.

In some embodiments, the mask M1 may include a multi-layer reflective layer disposed on the substrate M11 and configured to reflect light or extreme ultraviolet light. The multilayer complex reflective layer includes a plurality of film pairs (film pairs), such as molybdenum-silicon (Mo/Si) film pairs, wherein in each film pair, one layer of molybdenum is disposed on top of or below another layer of silicon. In some embodiments, the film pairs may Be molybdenum-beryllium (Mo/Be) film pairs, or other suitable materials that are highly reflective of ultraviolet light.

The mask M1 may further include a pattern layer M12 disposed on the substrate M11. The patterned patterning layer M12 may be used to define an Integrated Circuit (IC). When the light (extreme ultraviolet) emitted from the illumination device 30 irradiates the patterned layer M12, a patterned light is formed.

In some embodiments, the patterned layer M12 may be an absorbent layer. The absorption layer may include TaBN (tanalum boronnide) for absorbing light or extreme ultraviolet rays. In some embodiments, mask M1 may be an extreme ultraviolet phase shift mask M1(EUV phase shift mask), and pattern layer M12 may be a reflective layer.

An optical projection device (POB) 50 is disposed between the mask M1 and the wafer pedestal 60 for forming a pattern of the mask M1 on the wafer W1. In some embodiments, the optical projection device 50 may include a plurality of optical elements, such as at least one lens, at least one mirror, and/or at least one refractor. The light emitted from the mask M1 carries an image of the pattern defined on the mask M1 and is refracted, reflected, and/or condensed by the optical projection device 50 and directed toward the wafer W1 or the wafer pedestal 60.

In the present embodiment, the optical projection apparatus 50 includes a plurality of reflectors 51 for reflecting light (or extreme ultraviolet rays). The light emitted from the mask M1 is reflected and condensed by the optical projection device 50 and then directed to the wafer W1 or the wafer stage 60.

The wafer holder 60 is disposed below the mask M1. In the present embodiment, the wafer stage 60 is disposed below the optical projection apparatus 50. The wafer holder 60 is used to hold the wafer W1. The wafer pedestal 60 may be an electrostatic chuck (e-chuck).

The wafer W1 may be made of silicon or other semiconductor material. In some embodiments, the wafer W1 may be made of a compound semiconductor (compound semiconductor) material, such as silicon carbide (SiC), gallium arsenide (GaAs), indium arsenide (InAs), or indium phosphide (InP). In some embodiments, the wafer W1 may be made of an alloy semiconductor (alloy semiconductor), such as silicon germanium (SiGe), silicon carbide (SiGeC), gallium arsenide phosphide (GaAsP), or gallium indium phosphide (GaInP). In some embodiments, the wafer W1 may be a silicon-on-insulator (SOI) or germanium-on-silicon (GOI) substrate.

In addition, the wafer W1 may have various device elements (device elements). For example, the device elements formed on the wafer W1 may include transistors (transistors), diodes (diodes), and/or other suitable elements. A variety of different processes may be used to form the device elements described above. Such as a deposition process, an etching process, an implantation process, a photolithography process, and/or other suitable processes.

In some embodiments, the wafer W1 is coated with a photoresist layer W11 that is chemically reactive to light (or ultraviolet light). When the patterning light emitted from the optical projection apparatus 50 is irradiated to the photoresist layer W11, the photoresist layer W11 may be patterned.

The light source device 10 may use a dual-pulse laser plasma (dual-pulse LPP) mechanism to generate plasma from the target E1 and emit extreme ultraviolet light from the plasma. The light source device 10 may include an excitation chamber A10, a target emitter A20, a target recycler A30, a light collector A50, a pre-laser emitter A60, a main laser emitter A70, a laser supply device A80, and a laser vacuum device A90.

The light source device 10 may include all of the above devices, but need not include all of the above devices as long as the purpose of using the light source device 10 is achieved. The light source apparatus 10 should not be limited to the apparatus described in the present disclosure and may include other suitable elements.

The excitation chamber a10 may be located on one side of the exposure chamber 20. The excitation chamber A10 may be connected to the exposure chamber 20 via a light path A11. Since the gas molecules will absorb the extreme ultraviolet light, a vacuum may be maintained inside excitation chamber a10 to prevent loss of the extreme ultraviolet light.

It is noted that in some embodiments, after the excitation chamber a10 is filled with a gas such as hydrogen, the excitation chamber a10 is pumped into a vacuum state by a vacuum pump. At this point, a small amount of gas remains in the excitation chamber a 10. In some embodiments, the pressure within the excitation chamber a10 may be less than or equal to about 0.001 atmosphere.

Target emitter a20 is disposed on firing chamber a10 and is operable to generate a plurality of target E1. In this embodiment, target emitter A20 may be located within excitation chamber A10. Target emitter A20 may emit target E1 in a first direction D1 toward an excitation zone Z1 within excitation chamber A10, and the target E1 passes through a transmission zone Z3 between target emitter A20 and excitation zone Z1.

Target E1 may be liquid or solid. In the present embodiment, the target E1 may be in a liquid state and may be a tin droplet (tindrop). In some embodiments, the target E1 may be a liquid material including tin, such as eutectic alloy (eutectic alloy) including tin, lithium (Li), and xenon (Xe). In some embodiments, the target E1 has a diameter in the range of about 20 μm to about 40 μm. In this embodiment, the target E1 may be about 30 μm in diameter. In some embodiments, target launcher A20 may emit target E1 at speeds above 50 meters per second. In this embodiment, target launcher A20 may emit target E1 at a speed of about 70 meters per second to about 90 meters per second

Target transmitter A20 may transmit a target E1 frequency in a range between about 40kHz and 300 kHz. In other words, target transmitter A20 may transmit a target E1 in a range of approximately every 3.3 microseconds to 25 microseconds. In some embodiments, target emitter A20 emits target E1 frequency in the range of 50kHz to 80 kHz.

In some embodiments, target emitter A20 generates a target E1 frequency that may be in a range of about 60kHz to 300 kHz. In other words, target transmitter A20 may transmit a target E1 in a range of approximately every 3.3 microseconds to 16.7 microseconds. In the present embodiment, target transmitter A20 may generate a target E1 frequency of about 100 kHz. In other words, target emitter A20 may emit a target E1 approximately every 10 microseconds.

Target retriever a30 is disposed in excitation chamber a10 to retrieve target E1 emitted from target emitter a 20. In this embodiment, target retriever a30 is located within excitation chamber a 10. Target retriever a30 and target emitter a20 may be on opposite sides of firing chamber a 10. In the present embodiment, excitation zone Z1 is located between target retriever a30 and target emitter a 20.

A light collector A50 is disposed in the excitation chamber A10 for collecting EUV light in a light collecting region Z2. In some embodiments, the condensation zone Z2 is located in the illumination device 30. The light collector A50 is used to reflect the extreme ultraviolet light and transmit the extreme ultraviolet light to the illuminator 30 in the exposure chamber 20 via the light channel A11.

In the present embodiment, the light collector a50 may be an elliptic paraboloid. The light concentrator a50 may be coated with a reflective layer to reflect extreme ultraviolet light. The light collector A50 may have a through hole A51 for passing the pre-pulse laser light L1 and the main pulse laser light L2 emitted from the pre-laser emitter A60 and the main laser emitter A70. In some embodiments, the diameter of the through-hole a51 is in a range of about 10cm to about 20 cm.

In the present embodiment, the light collector A50 can be, for example, an elliptical lens having a first focal point C1 located in the excitation region Z1 and a second focal point C2 located in the light-collecting region Z2. When the target E1 excites euv light at the first focus C1 after being irradiated by the main pulse laser L2 emitted from the main laser emitter a70, the euv light may be reflected to the second focus C2 by the light collector a 50. Since the second focal point C2 can be located in the illumination device 30 in the light converging region Z2, the euv light can be focused on the illumination device 30 by the light concentrator a50 in the present embodiment.

In some embodiments, the second focal point C2 may be located in the excitation cavity a10 or the light channel a11, and the uv light at the second focal point C2 may be transmitted to the illumination device 30 through suitable optical elements, such as refractors or reflectors.

It should be noted that the shape or structure of the light collector A50 is not limited as long as the ultraviolet light emitted from the target E1 can be collected in a region. For example, the light collector a50 may be parabolic.

Pre-laser emitter A60 is disposed on one side of firing chamber A10. In this embodiment, pre-laser emitter A60 may be located within firing chamber A10. Pre-laser emitter A60 may be used to generate a pre-pulse laser (pre-pulse laser) L1 to target E1 within excitation region Z1. The pre-pulse laser light L1 passes through the light collector a50 via the through hole a51 and is irradiated to the excitation region Z1.

In the present embodiment, the pre-laser emitter A60 emits the pre-pulse laser L1 along a second direction D2. The second direction D2 may be perpendicular to the first direction D1. In certain embodiments, pre-laser launcher a60 may emit pre-pulsed laser light L1 at the same frequency that target launcher a20 emits target E1.

In some embodiments, the power of the pre-pulse laser L1 is in a range of about 1kW to about 4 kW. In the present embodiment, the power of the pre-pulse laser L1 may be about 2 kW.

In some embodiments, pre-laser emitter A60 may be a carbon dioxide (CO)₂) A laser emitter. In another embodiment, the pre-laser emitter A60 may be a neodymium-doped yttrium aluminum garnet (Nd: YAG) laser emitter.

Primary laser emitter a70 is disposed on one side of firing chamber a 10. In this embodiment, primary laser emitter A70 may be located within firing chamber A10. The main laser emitter A70 may be used to generate a main-pulse laser (main-pulse laser) L2 to target E1 within the excitation region Z1. The main pulse laser light L2 can pass through the light collector a50 via the same through hole a51 and irradiate to the excitation region Z1.

In some embodiments, the main laser emitter a70 may emit the main pulse laser light L2 in the second direction D2. In other words, the main pulse laser L2 may be parallel to the pre-pulse laser L1. The distance between the pre-pulse laser L1 and the main pulse laser L2 may be about 1 μm.

In some embodiments, the power of the main pulse laser L2 is in a range of about 18kW to 40 kW. In the present embodiment, the power of the main pulse laser L2 may be about 30 kW. The power of the main pulse laser light L2 is greater than that of the pre-pulse laser light L1. In some embodiments, the power of the main pulse laser L2 is 8 times to 30 times greater than the power of the pre-pulse laser L1.

In some embodiments, the frequency at which the master laser launcher a70 emits the master pulse laser light L2 may be the same as the frequency at which the target launcher a20 emits the target E1. In some embodiments, primary laser emitter a70 may be a carbon dioxide laser emitter.

In some embodiments, the pre-pulse laser L1 has a smaller spot size (spotsize) than the main pulse laser L2. In some embodiments, the spot size of the pre-pulse laser L1 is in the range of about 250 μm to about 350 μm. The spot size of the main pulse laser light L2 is approximately in the range of 300 μm to 600 μm.

The pre-pulse laser L1 may have a power of 2kW, and the main pulse laser L2 may have a power of about 30 kW. In some embodiments, the sum of the power of the pre-pulse laser L1 and the main pulse laser L2 is higher than 20kW, for example, 32 kW. It should be understood, however, that there are many variations and modifications of the embodiments of the present disclosure, which should not be taken to be limiting.

As shown in fig. 1, a pre-pulsed laser L1 may be used to change the state of target E1. After the pre-pulse laser L1 is irradiated to target E1 in the excitation region Z1, the pre-pulse laser L1 can heat the target E1 to make the droplet-shaped target E1 form mist target E1. When the main pulse laser light L2 is irradiated to the atomized target E1 in the excitation region Z1, the atomized target E1 is excited into plasma, and extreme ultraviolet rays are generated in the plasma.

The laser supply device a80 is disposed at one side of the light source device 10 for supplying laser light to the main laser emitter a 70. The laser supply device a80 may include a seed laser generator a81, and a plurality of power amplifiers a 82. The seed laser generator A81 may provide laser light to the power amplifier A82. The laser power is increased when the laser power supplied from the seed laser generator a81 passes through the power amplifier a 82.

For example, the power of the laser generated by the seed laser generator a81 is 1W. After passing through the plurality of power amplifiers a82, the power of the laser was 30 kW.

In some embodiments, the laser supply a80 may supply laser light to the pre-laser launcher a60 and/or the laser vacuum a 90. In some embodiments, the laser light for pre-laser launcher a60 and laser vacuum a90 may be provided via other suitable laser light supply devices.

The laser vacuum apparatus A90 is disposed on the excitation chamber A10 and is used to generate a vacuum laser L3 into the excitation chamber A10 and through the transport region Z3. The vacuum laser L3 within the firing chamber A10 may be delivered generally in the first direction D1. In the present embodiment, the vacuum laser L3 is reflected by a mirror B1 into the excitation cavity a 10. In some embodiments, the laser vacuum a90 is located on one side of the target emitter a20, and the vacuum laser L3 may directly illuminate the excitation cavity a10 without passing through the mirror B1.

The vacuum laser L3 passes through the excitation zone Z1 and the transport zone Z3 to ionize the gas in the excitation zone Z1 and the transport zone Z3 to form a vacuum channel Z4 (as shown in FIG. 4B). The vacuum channel Z4 encompasses the travel route of target E1. In other words, within vacuum channel Z4, the pressure (or gas density) of the travel path of target E1 is less than the pressure (or gas density) of vacuum laser L3 prior to formation through vacuum channel Z4.

In some embodiments, laser vacuum A90 is a carbon dioxide laser emitter. In another embodiment, the pre-laser emitter a60 may be a neodymium-doped yttrium aluminum garnet laser emitter.

In some embodiments, the frequency at which laser vacuum A90 emits vacuum laser light L3 may be the same as the frequency at which target emitter A20 emits target E1. In some embodiments, the spot size of vacuum laser L3 is about 100 μm or less than 100 μm. The power of the vacuum laser L3 is in the range of 100W to 500W, and in the present embodiment, the power of the vacuum laser L3 is about 200W.

In this embodiment, the power of the vacuum laser L3 is less than the power of the pre-pulse laser L1 and the power of the main pulse laser L2, and the light intensity of the vacuum laser L3 is greater than 10^8(W/cm 2). Therefore, when the vacuum laser L3 is irradiated to the target E1, the target E1 is not atomized or plasma-formed, and the vacuum channel Z4 can be formed.

FIG. 2 is a flow chart of steps of a lithographic method according to some embodiments of the present disclosure. FIG. 3 is a timing diagram of a photolithography method according to some embodiments of the present disclosure. It is understood that in the steps of the methods of the following embodiments, additional steps may be added before, after, and between the steps, and some of the steps may be replaced, deleted, or moved.

In step S101, a mask M1 is mounted on the mask holder 41. In some embodiments, mask M1 may be used to perform an euv lithography exposure process. Mask M1 may include integrated circuit patterns for forming on wafer W1. In step S103, a wafer W1 is disposed on a wafer pedestal 60. Wafer W1 may be coated with a photoresist layer W11.

In step S105, the laser vacuum apparatus a90 emits a vacuum laser L3 into the excitation chamber a10 and through the excitation region Z1 and the transport region Z3 every time a first interval P1 elapses. In this embodiment, the first interval P1 may be 10 μ s. In some embodiments, the first interval P1 may be in a range from about 3.3 microseconds to about 25 microseconds. In some embodiments, the first interval P1 may be between about 3.3 microseconds and about 16.7 microseconds.

Fig. 4A and 4B are schematic diagrams of the lithographic apparatus 1 at an intermediate stage of a lithographic method according to some embodiments of the present disclosure. As shown in fig. 1 and 4A, the gas G1 is distributed within the excitation chamber a10 before the vacuum laser L3 is emitted. At this time, the gas pressure (or gas density) in the excitation zone Z1 and the transport zone Z2 is equal to the gas pressure (or gas density) in the excitation chamber a 10. For example, the pressure within the excitation chamber a10 may be less than or equal to about 0.001 atmosphere.

In addition, when target E1 becomes a plasma, the gas G1 in the excitation chamber A10 generates a seismic wave S1. The seismic wave S1 spreads out to the wall of the excitation chamber a10 and the optical projection apparatus 50 through the first focus C1, and enters the excitation region Z1 and the transmission region Z2. At this time, if target E1 travels in the excitation region Z1 and the propagation region Z2, the seismic wave S1 will affect the traveling path of target E1, and some target E1 cannot or accurately be hit by the pre-pulse laser L1 and/or the main pulse laser L2 in the excitation region Z1.

When target E1 cannot be hit by the main pulse laser L2 or is precisely hit by the main pulse laser, the amount of extreme ultraviolet light is reduced, and the wafer W1 is improperly exposed. When the wafer W1 is improperly exposed, the exposure process may need to be performed again, thereby reducing the throughput of the wafer W1. In severe cases, the wafer W1 may need to be scrapped.

As shown in fig. 1, 4A, and 4B, after the vacuum laser L3 is emitted, the vacuum laser L3 dissociates the gas G1 into a plasma state with positive and negative charges. In some embodiments, gas G1 forms electrons G2 and ions G3. At this time, the electron G2 and the ion G3 move in a direction away from the vacuum laser L3. In addition, since the electron G2 moves away from the vacuum laser L3 faster than the ion G3, the attraction of the electron G2 to the ion G3 can further increase the movement of the ion G3 away from the vacuum laser L3, thereby temporarily forming the vacuum channel Z4. Thereafter, the electron G2 will revert to a neutral gas of gas G1 when combined with the ion G3, and a portion of the gas G1 will fill the vacuum channel Z4.

The vacuum channel Z4 in this embodiment is defined as the pressure (or gas density) in the vacuum channel Z4 being less than the average pressure (or gas density) in the firing chamber a 10. For example, the pressure within the vacuum channel Z4 may be less than 0.0001 atmosphere and the average pressure within the excitation chamber A10 may be less than 0.001 atmosphere. In other words, the pressure in the vacuum channel Z4 can be less than ten times the average pressure (or gas density) in the excitation chamber a10 before the vacuum laser L3 fires.

In step S107, the target emitter a20 emits a target E1 every time the first interval time P1 elapses, and the target E1 reaches the excitation region Z1 via the vacuum channel Z4. In some embodiments, the laser vacuum apparatus a90 emits the vacuum laser L3 at a first time T1 and the target emitter a20 emits the target E1 at a second time T2. The second time T2 is later than the first time T1. For example, the time difference between the second time T2 and the first time T1 may be less than 1 microsecond.

As shown in fig. 1 and 4B, when target launcher a20 launches target E1, target E1 may reach excitation region Z1 via vacuum channel Z4 due to the formation of vacuum channel Z4 within transport region Z3.

In the present embodiment, since the gas pressure (or gas density) in the vacuum channel Z4 generated after the irradiation of the vacuum laser L3 is small, the seismic wave S1 in the vacuum channel Z4 is greatly attenuated, thereby reducing the degree of the impact of the seismic wave S1 on the traveling route of the target E1. The pre-pulse laser L1 and the main pulse laser L2 can strike the winning E1 more accurately. In addition, in the present embodiment, since the target transmitter a20 may not need to transmit the target E1 after the seismic wave S1 dissipates, the frequency of the target transmitter a20 transmitting the target E1, the frequency of the pre-laser transmitter a60 transmitting the pre-pulse laser L1, and the frequency of the main laser transmitter a70 transmitting the main pulse laser L2 may be increased, so as to increase the amount of the extreme ultraviolet rays, thereby reducing the exposure time required for the wafer W1.

In some embodiments, when lithographic apparatus 1 does not include laser vacuum A90, target emitter A20 may emit target E1 at a frequency of 50 kHz. In some embodiments, the frequency at which target emitter a20 emits target E1 may be increased to 80kHz, 90kHz, or 100kHz by vacuum laser L3 emitted by laser vacuum apparatus a 90.

In step S109, the pre-laser emitter a60 emits a pre-pulse laser L1 to the excitation region Z1 every time the first interval P1 elapses, and irradiates a target E1. Target E1 may form atomized target E1 via pre-pulsed laser L1.

In some embodiments, the pre-laser emitter a60 emits at a third time T3. The third time T3 is later than the second time T2.

In step S111, the main laser emitter a70 emits a main pulse laser L2 to the excitation region Z1 every time the first interval P1 elapses, and irradiates a target E1. Target E1 can form plasma via main pulse laser L2 and emit ultraviolet light.

In some embodiments, the pre-laser emitter a60 emits at a fourth time T4. The fourth time T4 is later than the third time T3. For example, the time difference between the fourth time T4 and the third time T3 may be less than 1 microsecond.

In some embodiments, the master laser transmitter a70 transmits the master pulsed laser light L2 at the second interval P2 of the target E1 of the target transmitter a 20. The second interval time P2 may be in a range of 3 microseconds to 22 microseconds. In this embodiment, the third interval P3 may be about 7 μ s.

In some embodiments, the laser vacuum apparatus a90 emits the vacuum laser light L3 at a third interval P3 after the main laser emitter a70 emits the main pulse laser light L2. The third interval P3 may be in a range of 2 microseconds to 20 microseconds. In the present embodiment, the third interval P3 may be about 3 microseconds

For example, when the lithographic apparatus 1 does not include the laser vacuum a90, the third interval P3 is greater than 8 microseconds. The third interval time P3 may be less than 7 microseconds by the vacuum laser L3 emitted by the laser vacuum apparatus a 90. In some embodiments, the third interval P3 may be in a range of about 3 microseconds to about 5 microseconds.

In step S113, the EUV light is sequentially directed to the mask M1 via the light collector A50 and the illumination device 30, and a patterned light is formed. The patterned light is sequentially irradiated to a plurality of regions of the photoresist of a wafer W1, thereby completing an exposure process of a photolithography process.

In summary, the photolithography apparatus according to the embodiment of the disclosure uses the laser vacuum device to form a vacuum channel on the target traveling path first, so as to greatly reduce the influence of the shock wave generated when the target traveling path is irradiated by the main pulse laser, and further increase the accuracy of the main laser emitter in targeting.

The present disclosure provides a lithographic apparatus including an excitation chamber, a target emitter, a main laser emitter, and a laser vacuum. The target emitter is used for emitting a target towards an excitation area in the excitation cavity. The main laser emitter is used for emitting a main pulse laser to a target in the excitation area. The laser vacuum device is used for emitting a vacuum laser into the excitation cavity and forming a vacuum channel in the excitation cavity. After the laser vacuum device emits the vacuum laser, the target emitter emits the target through the vacuum channel into the excitation area.

In some embodiments, the frequency at which the primary laser emitter emits the primary pulsed laser light, the frequency at which the target emitter emits the target, and the frequency at which the laser vacuum apparatus emits the vacuum laser light are the same.

In some embodiments, the lithographic apparatus further comprises a pre-laser emitter configured to emit a pre-pulse laser to a target within the excitation region, wherein after the target emitter emits the target, the pre-pulse laser and the main laser emitter sequentially emit the pre-pulse laser and the main laser.

In some embodiments, the pre-laser emitter emits the pre-pulse laser at the same frequency as the laser vacuum apparatus emits the vacuum laser.

In some embodiments, the power of the vacuum laser is less than the power of the pre-pulse laser and the power of the main pulse laser.

In some embodiments, the target emitter emits the target in a first direction, the laser vacuum apparatus emits the vacuum laser substantially in the first direction, and the main laser emitter emits the main pulse laser in a second direction, wherein the first direction is different from the second direction.

The present disclosure provides a lithographic apparatus including a laser vacuum and a target emitter. The laser vacuum device is used for emitting vacuum laser into an excitation cavity along a first direction approximately so as to form a vacuum channel in the excitation cavity. The target emitter is configured to emit a target in a first direction, wherein the target passes through the vacuum channel to an excitation region.

The disclosure provides a photolithography method, which includes emitting a vacuum laser into an excitation chamber via a laser vacuum device to form a vacuum channel in the excitation chamber; after the vacuum laser is emitted, emitting a target by a target emitter, wherein the target is transmitted to an excitation area through a vacuum channel; and emitting a primary pulse laser to a target within the excitation region via a primary laser emitter.

In some embodiments, a pre-pulse laser is emitted to a target within the excitation area via a pre-laser emitter before the main pulse laser irradiates the target within the excitation area. The power of the vacuum laser is less than the power of the pre-pulse laser and the power of the main pulse laser.

In some embodiments, the vacuum laser ionizes the gas within the excitation chamber to form a vacuum channel.

The above-disclosed features may be combined, modified, replaced, or transposed with respect to one or more disclosed embodiments in any suitable manner, and are not limited to a particular embodiment.

While the foregoing is directed to embodiments of the present invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow. Therefore, the above embodiments should not be taken as limiting the scope of the invention, which is defined by the following claims.