Immersed laser direct writing photoetching device and method

Abstract

The invention provides an immersed laser direct-writing photoetching method and device. The immersed laser direct-writing photoetching device comprises a laser light source, a laser beam splitter, an acousto-optic modulator, a dichroscope-spectroscope module, an acousto-optic deflector, an objective lens, an immersion head and a motion platform, the motion platform is used for placing a wafer to be photoetched; the laser light source, the laser beam splitter, the acousto-optic modulator and the dichroscope-spectroscope module are sequentially arranged along a first straight line, the dichroscope-spectroscope module is arranged in a deflection mode relative to the first straight line, and the acousto-optic deflector, the objective lens, the immersion head and the motion platform are sequentially arranged along a second straight line; laser generated by the laser light source sequentially passes through the laser beam splitter and the acousto-optic modulator and is emitted to the dichroscope-spectroscope module, the dichroscope-spectroscope module selectively reflects laser with specific wavelength, and the reflected laser sequentially passes through the acousto-optic deflector, the objective lens and the immersion head and is emitted to a wafer to be photoetched. And high-speed and high-flux parallel laser scanning direct writing photoetching can be realized.

Description

Technical Field

[0001] The present invention relates to the technical field of laser direct writing lithography, and in particular to an immersion laser direct writing lithography device and method. Background Art

[0002] Laser direct writing lithography processing technology has the advantages of direct scanning exposure without mask, fast iteration speed of different production schemes, and higher flexibility; it also has the advantages of high precision, high efficiency and low cost; immersion laser direct writing lithography can reduce the number of optical elements in the projection system, control aberrations and thermal effects, and achieve the needs of larger numerical aperture. Its processing resolution can reach sub-micron level or even higher, and the corresponding processing technology is also greatly simplified. All of the above are crucial for the research, application, and trial production of new microelectronic devices in the fields of microelectronics and semiconductors. When used in the field of micro-nano processing, more sophisticated and complex micro devices can be produced. Direct writing lithography technology does not require a mask, and has obvious advantages in shortening the process, automatic expansion and contraction, multi-layer alignment, small-volume and multi-variety production, curved surface exposure, and the construction of a one-piece-one-code smart factory.

[0003] Laser direct writing lithography processing technology can be roughly divided into two main types according to the different radiation sources: one is direct writing lithography (CPML) based on charged particles, including electron beam direct writing, ion beam direct writing, etc.; the other is direct writing lithography (OML) based on optical projection, including interference lithography, laser direct writing lithography, and lithography technology based on spatial light modulators, etc.

[0004] The three major performance indicators of lithography machines are: overlay accuracy, resolution and production efficiency. Analyzing them one by one, among them, the direct writing lithography (electron beam direct writing, etc.) processing technology based on charged particles, although the electron beam scanning speed is fast, because the electron beam can only perform single-point scanning and the single scanning range is limited, the actual lithography processing efficiency is very low, resulting in the lithography capacity not meeting the actual needs; and in large-scale production, it will produce a more serious proximity effect, which seriously affects the resolution and accuracy of the graphics. Although the direct writing lithography processing technology based on optical projection can increase the single scanning processing area through the design of the optical system and correspondingly improve the production efficiency, it is limited by the high production cost of lithography projection devices (such as digital micromirror devices), insufficient projection resolution and response frequency, and the uniformity, distortion, and graphic splicing problems of the illumination and imaging modules in the overall optical system. As a result, the resolution of direct writing lithography based on optical projection is low and not suitable for high-precision processing. As for other conventional mechanical scanning lithography processing technologies, they all have similar problems of insufficient production capacity and accuracy as mentioned above.

[0005] In summary, the current laser direct writing lithography processing technology is mainly based on the serial processing method, which has low efficiency in line-by-line writing, and the processing time is proportional to the cube of the object size. It takes a long time to process a single micro-nano structure. In addition, there are problems such as the limitation of optical devices that make it difficult to improve the processing accuracy. In order to overcome the problems of low efficiency and insufficient processing accuracy of the serial processing method, an improved immersion laser direct writing lithography device and method are urgently needed. Summary of the invention

[0006] 1. Technical issues to be resolved

[0007] In view of the problems existing in the above technologies, the present invention solves them at least to a certain extent. To this end, the purpose of the present invention is to provide an immersion laser direct writing lithography device and method, which can realize high-speed and high-throughput parallel laser scanning direct writing lithography and improve the efficiency, accuracy and quality of direct writing lithography.

[0008] (II) Technical solution

[0009] In order to achieve the above object, the main technical solutions adopted by the present invention include:

[0010] In a first aspect, the present invention provides an immersion laser direct writing lithography method, comprising: splitting the laser generated by a laser light source to obtain multi-point parallel lasers; modulating and deflecting the multi-point parallel lasers to obtain multi-point parallel laser beams with specific separation angles; emitting the multi-point parallel laser beams through an immersion liquid layer to a wafer to be photolithographically formed a target pattern on the surface of the wafer to be photolithographically formed.

[0011] In a second aspect, the present invention provides an immersion laser direct writing lithography device, comprising a laser light source, a laser beam splitter, an acousto-optic modulator, a dichroic mirror-beam splitter module, an acousto-optic deflector, an objective lens, an immersion head and a motion platform; the motion platform is used to place a wafer to be photolithographically processed;

[0012] A laser light source, a laser beam splitter, an acousto-optic modulator and a dichroic mirror-beamsplitter module are arranged in sequence along a first straight line, the dichroic mirror-beamsplitter module is deflected relative to the first straight line, and an acousto-optic deflector, an objective lens, an immersion head and a motion platform are arranged in sequence along a second straight line; laser light generated by the laser light source is emitted to the dichroic mirror-beamsplitter module through the laser beam splitter and the acousto-optic modulator in sequence, the dichroic mirror-beamsplitter module selectively reflects laser light of a specific wavelength, and the reflected laser light is emitted to a wafer to be photolithographically processed through the acousto-optic deflector, the objective lens and the immersion head in sequence.

[0013] Optionally, the laser light source, laser beam splitter, acousto-optic modulator and dichroic mirror-beamsplitter module are arranged in sequence along a first straight line in the horizontal direction, and the acousto-optic deflector, objective lens, immersion head and motion platform are arranged in sequence along a second straight line in the gravity direction.

[0014] Optionally, the immersion laser direct writing lithography apparatus further includes an active focusing module, which is connected to the objective lens, and the active focusing module is used to adjust the distance between the objective lens and the wafer to be photolithographic according to the surface flatness of the wafer to be photolithographic.

[0015] Optionally, the immersion laser direct writing lithography apparatus further comprises a camera, a first lens, an illumination light source, a second lens and a prism assembly, the camera, the first lens and the prism assembly are sequentially arranged along a second straight line, the camera, the first lens and the prism assembly are all located on the upper side of the dichroic mirror-beam splitter module, the acousto-optic deflector, the objective lens, the immersion head and the motion platform are all located on the lower side of the dichroic mirror-beam splitter module, and the illumination light source, the second lens and the prism assembly are sequentially arranged along a third straight line in the horizontal direction;

[0016] The illumination light generated by the illumination light source is emitted to the prism assembly through the second lens. The prism assembly totally reflects the illumination light. The illumination light reflected by the prism assembly is sequentially emitted to the wafer to be photolithography through the dichroic mirror-beamsplitter module, the acousto-optic deflector, the objective lens and the immersion head. The illumination light reflected by the wafer to be photolithography is sequentially emitted to the camera through the immersion head, the objective lens, the acousto-optic deflector, the dichroic mirror-beamsplitter module, the prism assembly and the first lens.

[0017] Optionally, the motion platform is used to carry the wafer to be photolithographically processed, and to drive the wafer to be photolithographically processed to move in three directions: front-to-back, left-to-right, and up-down.

[0018] Optionally, the immersion laser direct writing lithography apparatus further includes a host computer, and the laser light source, laser beam splitter, acousto-optic modulator, acousto-optic deflector, immersion head, motion platform, active focusing module and camera are all communicatively connected to the host computer.

[0019] In a third aspect, the present invention provides a method for performing laser direct writing lithography using the immersion laser direct writing lithography apparatus as described above, comprising:

[0020] The laser beam splitter splits the laser beam generated by the laser light source to obtain multi-point parallel lasers; the acousto-optic modulator modulates the multi-point parallel lasers, and the acousto-optic deflector deflects the multi-point parallel lasers to obtain multi-point parallel laser beams with specific separation angles; the immersion head provides an immersion liquid layer between the objective lens and the wafer to be photolithography, and the multi-point parallel laser beams are emitted to the wafer to be photolithography through the immersion liquid layer to form a target pattern on the surface of the wafer to be photolithography.

[0021] Optionally, the laser beam splitter splits the laser beam generated by the laser light source according to the beam splitting signal sent by the host computer; the acousto-optic modulator modulates the multi-point parallel laser according to the modulation signal sent by the host computer; the acousto-optic deflector deflects the multi-point parallel laser according to the deflection signal sent by the host computer; the laser light source turns on and off the laser light source according to the on-off signal sent by the host computer; the immersion head forms an immersion liquid layer on the surface of the wafer to be photolithography according to the immersion instruction sent by the host computer; the active focusing module adjusts the distance between the objective lens and the wafer to be photolithography according to the focusing instruction sent by the host computer; the motion platform moves a specified stroke in the scanning direction according to the motion signal sent by the host computer; the host computer coordinates the operation of the laser light source, laser beam splitter, acousto-optic modulator, acousto-optic deflector, immersion head, motion platform and active focusing module according to a pre-set laser direct writing lithography program.

[0022] Optionally, the camera captures images in real time and sends the captured images to a host computer, which processes the images and monitors the laser direct writing lithography process.

[0023] (III) Beneficial effects

[0024] The beneficial effects of the present invention are:

[0025] The immersion laser direct writing lithography method and device provided by the present invention can generate multi-point laser beams with parallel outputs at specific angles and light intensities, thereby realizing high-speed and high-throughput parallel laser scanning direct writing lithography, greatly improving the efficiency, accuracy and quality of direct writing lithography, and meeting actual needs. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The present invention is described with the aid of the following drawings:

[0027] Figure 1 It is a schematic structural diagram of an immersion laser direct writing lithography device according to a specific embodiment of the present invention;

[0028] Figure 2 It is a schematic diagram of multi-point parallel laser beams after beam splitting, modulation and diffraction deflection according to a specific embodiment of the present invention.

[0029] [Reference Signs]

[0030] 1: Laser light source;

[0031] 11: camera; 12: first lens; 13: illumination light source; 14: second lens; 15: prism assembly;

[0032] 2: Laser beam splitter;

[0033] 3: Acousto-optic modulator;

[0034] 4: Dichroic mirror-beamsplitter module;

[0035] 5: Acousto-optic deflector;

[0036] 6: objective lens; 61: active focusing module;

[0037] 7: Immersion head;

[0038] 8: Sports platform;

[0039] 9: Waiting for photolithography wafer;

[0040] 10: Host computer. DETAILED DESCRIPTION

[0041] In order to better explain the present invention and facilitate understanding, the present invention is described in detail below with reference to the accompanying drawings and through specific embodiments. Figure 1 The orientation is used as a reference.

[0042] The present invention provides an immersion laser direct writing lithography method, comprising: splitting the laser generated by a laser light source 1 to obtain multi-point parallel lasers; performing modulation and deflection processing on the multi-point parallel lasers to obtain multi-point parallel laser beams with specific separation angles; emitting the multi-point parallel laser beams to a wafer to be photolithographically processed 9 through an immersion liquid layer to form a target pattern on the surface of the wafer to be photolithographically processed 9.

[0043] The immersion laser direct writing lithography method provided by the present invention can generate multi-point laser beams with parallel outputs of specific angles and light intensities, thereby realizing high-speed and high-throughput parallel laser scanning direct writing lithography, greatly improving the efficiency, accuracy and quality of direct writing lithography, and meeting actual needs.

[0044] like Figure 1 As shown, the present invention provides an immersion laser direct writing lithography device for realizing the above-mentioned immersion laser direct writing lithography method. The immersion laser direct writing lithography device comprises a laser light source 1, a laser beam splitter 2, an acousto-optic modulator 3, a dichroic mirror-beam splitter module 4, an acousto-optic deflector 5, an objective lens 6, an immersion head 7 and a motion platform 8; the motion platform 8 is used to place a wafer 9 to be photolithographically processed; the laser light source 1, the laser beam splitter 2, the acousto-optic modulator 3 and the dichroic mirror-beam splitter module 4 are arranged in sequence along a first straight line, the dichroic mirror-beam splitter module 4 is deflected relative to the first straight line, the acousto-optic deflector 5, the objective lens 6, the immersion head 7 and the motion platform 8 are arranged in sequence along a second straight line; the laser light generated by the laser light source 1 is sequentially emitted to the dichroic mirror-beam splitter module 4 through the laser beam splitter 2 and the acousto-optic modulator 3, the dichroic mirror-beam splitter module 4 selectively reflects laser light of a specific wavelength, and the reflected laser light is sequentially emitted to the wafer 9 to be photolithographically processed through the acousto-optic deflector 5, the objective lens 6 and the immersion head 7.

[0045] The laser direct writing lithography device configured in this way can generate high-quality split, collimated, uniform multi-point parallel lasers through the laser beam splitter 2; through the acousto-optic modulator 3, the frequency, amplitude, and phase of the multi-point parallel laser can be modulated, and the laser power intensity can be controlled to modulate the incident light field into a light field of a specific shape (linear, surface or special shape); through the acousto-optic deflector 5, the deflection of the laser beam can be controlled, and the output light angle of the laser beam can be accurately controlled. Through the immersion head 7, a high-refractive-index liquid can be added between the last lens of the objective lens 6 and the wafer 9 to be photolithographically processed as a medium to increase the refraction degree of the light, which is equivalent to increasing the lens aperture size and numerical aperture. At the same time, the depth of focus and the tolerance of the exposure process can be significantly improved to achieve the purpose of improving the resolution. The combination of the acousto-optic modulator 3, the acousto-optic deflector 5 and the immersion head 7 can control the divergence angle of the light beam and the morphology of the formed light spot. After re-expansion and focusing, a parallel writing light beam composed of multiple sub-beams is formed (such as Figure 2 As shown, the laser beam is arranged in multiple rows at equal intervals for micro-nano lithography, realizing the function of the laser beam to form a specific pattern, thereby greatly improving the efficiency, accuracy and quality of direct writing lithography and meeting actual needs, that is, providing a suitable multi-point parallel laser beam for greatly improving lithography capacity and accuracy.

[0046] Preferably, the laser light source 1 is an ultraviolet laser light source, which is the only light source for direct-write lithography with a certain energy value.

[0047] Preferably, the laser light source 1, the laser beam splitter 2, the acousto-optic modulator 3 and the dichroic mirror-beam splitter module 4 are arranged in sequence along a first straight line in the horizontal direction, and the acousto-optic deflector 5, the objective lens 6, the immersion head 7 and the motion platform 8 are arranged in sequence along a second straight line in the gravity direction. In this way, the structure of the immersion laser direct writing lithography apparatus is more compact.

[0048] Preferably, the immersion laser direct writing lithography apparatus further includes an active focusing module 61, which is connected to the objective lens 6, and is used to adjust the distance between the objective lens 6 and the wafer 9 to be photolithographic according to the surface flatness of the wafer 9 to be photolithographic. In this way, the active focusing module 61 changes the position of the objective lens 6 in real time according to the fluctuation of the wafer flatness, ensures that the objective lens 6 is focused in real time, and ensures the exposure quality.

[0049] Preferably, the immersion laser direct writing lithography device also includes a camera 11, a first lens 12, an illumination light source 13, a second lens 14 and a prism assembly 15. The camera 11, the first lens 12 and the prism assembly 15 are arranged in sequence along a second straight line. The camera 11, the first lens 12 and the prism assembly 15 are all located on the upper side of the dichroic mirror-beamsplitter module 4. The acousto-optic deflector 5, the objective lens 6, the immersion head 7 and the motion platform 8 are all located on the lower side of the dichroic mirror-beamsplitter module 4. The illumination light source 13, the second lens 14 and the prism assembly 15 are arranged in sequence along a third straight line in the horizontal direction. The illumination light generated by the illumination light source 13 is emitted to the prism assembly 15 through the second lens 14, and the prism assembly 15 totally reflects the illumination light. The illumination light reflected by the prism assembly 15 is emitted to the wafer 9 to be photolithography through the dichroic mirror-beam splitter module 4, the acousto-optic deflector 5, the objective lens 6 and the immersion head 7 in sequence, and the illumination light reflected by the wafer 9 to be photolithography is emitted to the camera 11 through the immersion head 7, the objective lens 6, the acousto-optic deflector 5, the dichroic mirror-beam splitter module 4, the prism assembly 15 and the first lens 12 in sequence. In this way, it is possible to provide illumination support for laser direct writing lithography, and the camera 11 can be used to collect images of the laser direct writing lithography process in real time, providing data support for subsequent identification and monitoring of the laser direct writing lithography process.

[0050] Preferably, the motion platform 8 is used to carry the wafer 9 to be photoetched, and drive the wafer 9 to be photoetched to move in three directions: front, back, left, right, and top and bottom. In this way, the wafer 9 to be photoetched is driven to move, thereby realizing a high-speed direct-write photolithography process of any exposure pattern.

[0051] Preferably, the immersion laser direct writing lithography apparatus further includes a host computer 10, and the laser light source 1, the laser beam splitter 2, the acousto-optic modulator 3, the acousto-optic deflector 5, the immersion head 7, the motion platform 8, the active focusing module 61 and the camera 11 are all connected to the host computer 10 in communication. In this way, the host computer 10 can control each component (including the laser light source 1, the laser beam splitter 2, the acousto-optic modulator 3, the acousto-optic deflector 5, the immersion head 7, the motion platform 8, the active focusing module 61 and the camera 11) according to the GDS (Graphic Data System, storage image data system) lithography data file to ensure the coordinated operation of each component; in addition, the host computer 10 can also perform functions such as photoelectric signal conversion, processing of images collected by the camera 11, and transmission of massive data.

[0052] The method for performing laser direct writing lithography based on the above-mentioned immersion laser direct writing lithography device includes: a laser beam splitter 2 splits the laser beam generated by a laser light source 1 to obtain multi-point parallel lasers; an acousto-optic modulator 3 modulates the multi-point parallel lasers, and an acousto-optic deflector 5 deflects the multi-point parallel lasers to obtain multi-point parallel laser beams with specific separation angles; an immersion head 7 provides an immersion liquid layer between an objective lens 6 and a wafer 9 to be photolithographically processed, and the multi-point parallel laser beams are emitted to the wafer 9 to be photolithographically processed through the immersion liquid layer to form a target pattern on the surface of the wafer 9 to be photolithographically processed.

[0053] Further, the laser beam splitter 2 splits the laser beam generated by the laser light source 1 according to the beam splitting signal sent by the host computer 10; the acousto-optic modulator 3 modulates the multi-point parallel laser according to the modulation signal sent by the host computer 10; the acousto-optic deflector 5 deflects the multi-point parallel laser according to the deflection signal sent by the host computer 10; the laser light source 1 turns on and off the laser light source 1 according to the on-off signal sent by the host computer 10; the immersion head 7 is immersing according to the immersion instruction sent by the host computer 10. , an immersion liquid layer is formed on the surface of the wafer 9 to be photolithography; the active focusing module 61 adjusts the distance between the objective lens 6 and the wafer 9 to be photolithography according to the focusing instruction issued by the host computer 10; the motion platform 8 moves a specified stroke in the scanning direction according to the motion signal issued by the host computer 10; the host computer 10 coordinates the operation of the laser light source 1, the laser beam splitter 2, the acousto-optic modulator 3, the acousto-optic deflector 5, the immersion head 7, the motion platform 8 and the active focusing module 61 according to the pre-set laser direct writing lithography program.

[0054] After the host computer 10 sends relevant signals to the precision motion platform 8 and the laser beam splitting, modulation and deflection module, the multi-point parallel laser beam that meets the design requirements after beam splitting, modulation and diffraction deflection processing is finally projected onto the surface of the wafer to be exposed through the objective lens 6, the active focusing module 61 and the immersion head 7 for exposure lithography process; the motion platform 8 moves the specified stroke in the scanning direction according to the instructions issued by the host computer 10, and the multi-point parallel laser beam can complete a scanning stroke lithography exposure process on the wafer; after each scanning stroke lithography exposure process is completed, the motion platform 8 drives the wafer to move a stepping displacement slightly smaller than the beam size in the stepping direction perpendicular to the scanning direction; after the stepping is completed, the lithography exposure process of the next scanning stroke is immediately started until the direct writing lithography process within the entire wafer range is completed. Then the motion platform 8 continues to move the wafer to the wafer handover position for lithography post-process production process. During the lithography process, the host computer 10 autonomously controls the on and off of the beam, realizing high-speed parallel direct writing exposure lithography of any design pattern.

[0055] Furthermore, the camera 11 collects images in real time and sends the collected images to the host computer 10. The host computer 10 processes the images and monitors the laser direct writing lithography process.

[0056] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0057] In the present invention, unless otherwise clearly specified and limited, when a first feature is “on” or “below” a second feature, it may be that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Moreover, when a first feature is “above”, “above” or “above” a second feature, it may be that the first feature is directly above or obliquely above the second feature, or it may simply mean that the first feature is higher in level than the second feature. When a first feature is “below”, “below” or “below” a second feature, it may be that the first feature is directly below or obliquely below the second feature, or it may simply mean that the first feature is lower in level than the second feature.

[0058] In the description of this specification, the description of the terms "one embodiment", "some embodiments", "embodiment", "example", "specific example" or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, unless they are contradictory.

[0059] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may alter, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. An immersion laser direct writing lithography method, characterized in that: include: The laser light generated by the laser light source (1) is beam split to obtain multi-point parallel laser light; the multi-point parallel laser light is modulated and deflected to obtain multi-point parallel laser light beams with specific separation angles; the multi-point parallel laser light beams are emitted to a wafer to be photoetched (9) through an immersion liquid layer to form a target pattern on the surface of the wafer to be photoetched (9).

2. An immersion laser direct writing lithography device, characterized in that: It comprises a laser light source (1), a laser beam splitter (2), an acousto-optic modulator (3), a dichroic mirror-beam splitter module (4), an acousto-optic deflector (5), an objective lens (6), an immersion head (7) and a motion platform (8); The motion platform (8) is used to place the wafer (9) to be photoetched; A laser light source (1), a laser beam splitter (2), an acousto-optic modulator (3) and a dichroic mirror-beam splitter module (4) are arranged in sequence along a first straight line; the dichroic mirror-beam splitter module (4) is arranged to be deflected relative to the first straight line; an acousto-optic deflector (5), an objective lens (6), an immersion head (7) and a motion platform (8) are arranged in sequence along a second straight line; laser light generated by the laser light source (1) is emitted to the dichroic mirror-beam splitter module (4) through the laser beam splitter (2) and the acousto-optic modulator (3) in sequence; the dichroic mirror-beam splitter module (4) selectively reflects laser light of a specific wavelength; the reflected laser light is emitted to a wafer (9) to be photoetched through the acousto-optic deflector (5), the objective lens (6) and the immersion head (7) in sequence.

3. The immersion laser direct writing lithography apparatus according to claim 1, characterized in that: The laser light source (1), the laser beam splitter (2), the acousto-optic modulator (3) and the dichroic mirror-beam splitter module (4) are arranged in sequence along a first straight line in the horizontal direction, and the acousto-optic deflector (5), the objective lens (6), the immersion head (7) and the motion platform (8) are arranged in sequence along a second straight line in the gravity direction.

4. The immersion laser direct writing lithography apparatus according to claim 1, characterized in that: It also includes an active focusing module (61), which is connected to the objective lens (6), and is used to adjust the distance between the objective lens (6) and the wafer (9) to be photoetched according to the surface flatness of the wafer (9) to be photoetched.

5. The immersion laser direct writing lithography apparatus according to claim 4, characterized in that: It also includes a camera (11), a first lens (12), an illumination light source (13), a second lens (14) and a prism assembly (15); the camera (11), the first lens (12) and the prism assembly (15) are arranged in sequence along a second straight line; the camera (11), the first lens (12) and the prism assembly (15) are all located on the upper side of the dichroic mirror-beam splitter module (4); the acousto-optic deflector (5), the objective lens (6), the immersion head (7) and the motion platform (8) are all located on the lower side of the dichroic mirror-beam splitter module (4); and the illumination light source (13), the second lens (14) and the prism assembly (15) are arranged in sequence along a third straight line in the horizontal direction; The illumination light generated by the illumination light source (13) is emitted to the prism assembly (15) through the second lens (14); the prism assembly (15) totally reflects the illumination light; the illumination light reflected by the prism assembly (15) is emitted to the wafer to be photoetched (9) through the dichroic mirror-beam splitter module (4), the acousto-optic deflector (5), the objective lens (6) and the immersion head (7) in sequence; the illumination light reflected by the wafer to be photoetched (9) is emitted to the camera (11) through the immersion head (7), the objective lens (6), the acousto-optic deflector (5), the dichroic mirror-beam splitter module (4), the prism assembly (15) and the first lens (12) in sequence.

6. The immersion laser direct writing lithography apparatus according to claim 1, characterized in that: The motion platform (8) is used to carry the wafer (9) to be photoetched, and to drive the wafer (9) to be photoetched to move in three directions: front and back, left and right, and up and down.

7. The immersion laser direct writing lithography apparatus according to claim 5, characterized in that: It also includes a host computer (10), and the laser light source (1), the laser beam splitter (2), the acousto-optic modulator (3), the acousto-optic deflector (5), the immersion head (7), the motion platform (8), the active focusing module (61) and the camera (11) are all communicatively connected to the host computer (10).

8. A method for performing laser direct writing lithography using the immersion laser direct writing lithography apparatus according to any one of claims 2 to 7, characterized in that: include: The laser beam splitter (2) splits the laser beam generated by the laser light source (1) to obtain multi-point parallel laser beams; the acousto-optic modulator (3) modulates the multi-point parallel laser beams, and the acousto-optic deflector (5) deflects the multi-point parallel laser beams to obtain multi-point parallel laser beams with specific separation angles; the immersion head (7) provides an immersion liquid layer between the objective lens (6) and the wafer to be photoetched (9), and the multi-point parallel laser beams are emitted to the wafer to be photoetched (9) through the immersion liquid layer to form a target pattern on the surface of the wafer to be photoetched (9).

9. The laser direct writing lithography method according to claim 8, characterized in that: The laser beam splitter (2) splits the laser beam generated by the laser light source (1) according to the beam splitting signal sent by the host computer (10); the acousto-optic modulator (3) performs modulation processing on the multi-point parallel laser according to the modulation signal sent by the host computer (10); the acousto-optic deflector (5) performs deflection processing on the multi-point parallel laser according to the deflection signal sent by the host computer (10); the laser light source (1) turns on and off the laser light source (1) according to the on / off signal sent by the host computer (10); the immersion head (7) turns on the immersion instruction sent by the host computer (10) when the photolithography is to be performed. An immersion liquid layer is formed on the surface of the wafer (9); the active focusing module (61) adjusts the distance between the objective lens (6) and the wafer (9) to be photolithographically processed according to a focusing instruction sent by a host computer (10); the motion platform (8) moves within a specified stroke in a scanning direction according to a motion signal sent by the host computer (10); and the host computer (10) coordinates the operation of the laser light source (1), the laser beam splitter (2), the acousto-optic modulator (3), the acousto-optic deflector (5), the immersion head (7), the motion platform (8) and the active focusing module (61) according to a pre-set laser direct writing photolithography program.

10. The laser direct writing lithography method according to claim 9, characterized in that: The camera (11) collects images in real time and sends the collected images to the host computer (10). The host computer (10) processes the images and monitors the laser direct writing lithography process.

Images