DMD-based maskless photoetching imaging system and imaging method

Abstract

The invention discloses a maskless photoetching imaging system and method based on a DMD (Digital Micromirror Device), and the system achieves the uniform modulation of incident light through a uniform light module, thereby guaranteeing the uniform illumination of a target surface of the DMD; then, modulation of an exposure light field is completed through a DMD array group, digital control of an exposure pattern is achieved, and a digital mask pattern is obtained; and finally, on the basis, the digital mask pattern is multiplied and shrunk by using an imaging module and is projected to a wafer, so that maskless photoetching imaging can be completed. Therefore, compared with a traditional mask photoetching technology based on a mask plate, the digital mask pattern is used, and the mask plate and manufacturing equipment thereof are not needed, so that the mask manufacturing cost can be greatly reduced, the mask development time can be shortened, and the photoetching efficiency can be improved; therefore, the method is very suitable for large-scale application and popularization.

Description

Technical Field

[0001] The present invention relates to the technical field of maskless projection lithography, and particularly relates to a maskless lithography imaging system and an imaging method based on a DMD. Background Art

[0002] The development of lithography technology has continuously reduced the device feature size in integrated circuits, from the micron level to the sub-micron level, and now to the nanometer level. Therefore, as the resolution achieved by traditional lithography technology gradually approaches the theoretical limit, the difficulty of mask manufacturing is increasing, and the manufacturing process is becoming more and more complex (that is, corresponding mask manufacturing equipment needs to be configured to manufacture mask plates that meet the lithography conditions). As a result, the development time will increase significantly, and the manufacturing cost will increase sharply, resulting in insufficient mass production efficiency. Therefore, based on the above-mentioned defects, how to provide a maskless lithography imaging system that can reduce mask manufacturing costs and development time has become an urgent problem to be solved. Summary of the Invention

[0003] The technical problem to be solved by the present invention is the continuous increase in mask costs and the increasing difficulty of manufacturing. The purpose is to provide a maskless lithography imaging system and an imaging method based on a DMD, which solves the problems of high cost and long development time caused by the increasing difficulty of mask manufacturing and the increasing complexity of its manufacturing process in traditional technologies.

[0004] The present invention is achieved through the following technical solutions:

[0005] In the first aspect, a maskless lithography imaging system based on a DMD is provided, including:

[0006] A homogenizing module, wherein the homogenizing module is used to receive the incident light emitted by the light source group, adjust the incident light into uniform spot light that meets the lithography conditions, and emit the uniform spot light to the exposure module;

[0007] An exposure module, the exposure module includes a DMD array group, wherein the DMD array group is used to receive the exposure image and the uniform spot light, and generate exposure pattern light based on the exposure image and the uniform spot light and emit it to the imaging module;

[0008] An imaging module, which is used to receive the exposure pattern light emitted by the DMD array group, and perform a reduction process on the exposure pattern light to obtain reduced pattern light;

[0009] The imaging module is further used to project the reduced pattern light onto the wafer to complete the lithography process of the exposure image.

[0010] Based on the above - disclosed content, the present invention first uses a light - homogenizing module to adjust the incident light emitted by the light - source group, obtaining uniform spot light that meets the lithography conditions; then, uses a DMD array group (digital micromirror device) to receive the exposure image to be lithographed and the aforementioned uniform spot light, and in the DMD array group, generates exposure pattern light based on the aforementioned exposure image and uniform spot light. The principle of the DMD array group generating exposure pattern light is: controlling the deflection of each effective micro - mirror in the DMD array group to control the reflection of the incident light, thereby combining with the exposure image to generate a digital mask pattern (i.e., exposure pattern light); after completing the digital exposure modulation, the exposure pattern light can be emitted to the imaging module for demagnification processing to obtain demagnified pattern light; finally, projecting the demagnified pattern light onto the wafer can complete the lithography process of the exposure image.

[0011] Through the above design, the present invention realizes the homogenizing modulation of the incident light through the light - homogenizing module, thereby ensuring uniform illumination of the DMD target surface; then, through the DMD array group, completes the modulation of the exposure light field, realizes the digital control of the exposure pattern, and obtains a digital mask pattern; finally, on this basis, uses the imaging module to realize the demagnification of the digital mask pattern and project it onto the wafer, then the maskless lithography imaging can be completed. Thus, compared with the traditional mask - based lithography technology, the present invention uses a digital mask pattern, which does not require a mask and its manufacturing equipment. Based on this, not only can the mask manufacturing cost be greatly reduced, but also the mask development time can be reduced, and thus the lithography efficiency can be improved; therefore, the present invention is very suitable for large - scale application and promotion.

[0012] In a possible design, the light - homogenizing module includes: a light - homogenizing and collimating lens group, where the light - homogenizing and collimating lens group is used to perform light collimation and homogenization processing on the incident light, so as to generate uniform spot light that meets the lithography conditions after the light collimation and homogenization processing.

[0013] In a possible design, the light - homogenizing and collimating lens group includes: a focusing lens, a collimating lens, a fly - eye compound - eye lens, a diverging lens, and an output lens;

[0014] The focusing lens is used to focus the incident light to obtain focused light and output the focused light to the collimating lens;

[0015] The collimating lens is used to collimate the focused light to obtain collimated light and output the collimated light to the fly - eye compound - eye lens;

[0016] The fly - eye compound - eye lens is used to homogenize the collimated light to obtain uniform collimated light and output the uniform collimated light to the diverging lens;

[0017] A diverging lens is used to adjust the light divergence angle of the uniform collimated light, obtain uniform spot light, and emit the uniform spot light to the DMD array group through the output lens.

[0018] In a possible design, the light homogenizing module further includes a light inspection unit. The light inspection unit is used to perform light detection processing on the uniform spot light to obtain a light detection result, and the light detection includes spot size detection, light intensity distribution detection, and light collimation detection.

[0019] The light inspection unit is further used to judge whether the uniform spot light meets the lithography conditions based on the light detection result, and output a light adjustment prompt message when it is detected that the uniform spot light does not meet the lithography conditions.

[0020] In a possible design, a reflecting mirror is arranged on the light output path of the light homogenizing module. The reflecting mirror is used to reflect the uniform spot light emitted by the light homogenizing module into the exposure module.

[0021] In a possible design, the imaging module includes: a tube lens and a microscope group;

[0022] The tube lens is used to receive the exposure pattern light emitted by the DMD array group, perform a first reduction processing on the exposure pattern light, and obtain the first-reduced pattern light.

[0023] The tube lens is further used to perform a quasi-parallel processing on the first-reduced pattern light to obtain the processed reduced pattern light, and emit the processed reduced pattern light to the microscope group.

[0024] The microscope group is used to perform a second reduction processing on the processed reduced pattern light to obtain the reduced pattern light, and project the reduced pattern light onto the wafer.

[0025] In a possible design, the tube lens is used to focus the exposure pattern light at the target focus for the first reduction processing to obtain the first-reduced pattern light, where the target focus includes the first focal point of the tube lens.

[0026] In a possible design, the imaging module further includes: a beam splitter, a CCD camera group, and a controller;

[0027] The beam splitter is used to perform an optical path splitting process on the processed reduced pattern light emitted by the tube lens to obtain multiple paths of reduced pattern light, and emit the multiple paths of reduced pattern light to the CCD camera group through a lens, where each path of reduced pattern light corresponds to a lens respectively.

[0028] A CCD camera group, wherein each CCD camera in the CCD camera group respectively receives a path of reduced-scale graphic light, is used to generate an imaging image corresponding to the optical path, and transmits the corresponding imaging image to the controller;

[0029] A controller, which is used to perform image comparison processing on the imaging images of each optical path and a preset exposure image to obtain the imaging clarity of the processed reduced-scale graphic light, and outputs a hint information for adjusting the parameters of the light homogenization module when it detects that the imaging clarity does not meet the preset conditions.

[0030] In a possible design, the imaging module further includes: a graphic reduction detection unit, wherein the graphic reduction detection unit is used to perform reduction multiple detection processing on the once-reduced graphic light and the reduced graphic light to obtain a reduction multiple detection result;

[0031] The graphic reduction detection unit is also used to output a hint information for adjusting the parameters of the imaging component when it determines that the reduction multiple detection result does not meet the preset reduction conditions.

[0032] In a second aspect, a maskless lithography imaging method based on DMD is provided, wherein this method is implemented based on the maskless lithography imaging system according to the first aspect or any one of the possible designs in the first aspect, and the method includes:

[0033] The light homogenization module receives the incident light emitted by the light source group, adjusts the incident light into uniform spot light that meets the lithography conditions, and emits the uniform spot light to the DMD array group in the exposure module;

[0034] The DMD array group receives the exposure image and the uniform spot light, generates exposure graphic light based on the exposure image and the uniform spot light, and emits it to the imaging module;

[0035] The imaging module receives the exposure graphic light emitted by the DMD array group, performs reduction processing on the exposure graphic light to obtain reduced graphic light, and projects the reduced graphic light onto the wafer to complete the lithography processing of the exposure image.

[0036] In a third aspect, a maskless lithography imaging device based on DMD is provided. Taking the device as an electronic device as an example, it includes a memory, a processor, and a transceiver that are communicatively connected in sequence. Among them, the memory is used to store computer programs, the transceiver is used to send and receive messages, and the processor is used to read the computer programs and execute the maskless lithography imaging method according to the second aspect.

[0037] Fourthly, a storage medium is provided, on which instructions are stored. When the instructions run on a computer, they execute the DMD-based maskless lithography imaging method as described in the second aspect.

[0038] Fifthly, a computer program product containing instructions is provided. When the instructions run on a computer, the computer is made to execute the DMD-based maskless lithography imaging method as described in the second aspect.

[0039] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0040] (1) In the present invention, the homogenizing module is used to achieve the homogenizing modulation of the incident light, thereby ensuring the uniform illumination of the DMD target surface. Then, through the DMD array group, the modulation of the exposure light field is completed, the digital control of the exposure pattern is realized, and the digital mask pattern is obtained. Finally, on this basis, the imaging module is used to achieve the reduction of the digital mask pattern and project it onto the wafer, and thus the maskless lithography imaging can be completed. Therefore, compared with the traditional mask lithography technology based on a mask plate, the present invention uses a digital mask pattern, which does not require a mask plate and its manufacturing equipment. Based on this, not only can the mask manufacturing cost be greatly reduced, but also the mask development time can be reduced, and thus the lithography efficiency can be improved. Therefore, the present invention is very suitable for large-scale application and promotion.

[0041] (2) Compared with the traditional lithography technology based on a mask plate, the present invention uses a digital mask pattern and does not require a mask plate. Therefore, a mercury lamp can be not used as the light source. In this way, the problem of the short service life of the mercury lamp in the traditional mask lithography technology can be avoided. At the same time, the problem that the mask plate in the traditional technology is easily contaminated can also be avoided. Description of the Drawings

[0042] In order to more clearly illustrate the technical solutions of the exemplary embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention, and thus should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can also be obtained based on these drawings without creative efforts. In the drawings:

[0043] Figure 1 is a schematic structural diagram of a DMD-based maskless lithography imaging system provided by an embodiment of the present invention;

[0044] Figure 2 is a flowchart of the steps of a DMD-based maskless lithography imaging method provided by an embodiment of the present invention.

[0045] The labels in the drawings and the corresponding component names:

[0046] 10 - Light homogenizing and collimating lens group; 20 - DMD array group; 30 - Tube lens; 40 - Microscope group; 50 - Wafer; 60 - Reflecting mirror; 70 - Beam splitter; 80 - CCD camera group; 90 - Controller; 100 - Light source group. Detailed implementation manners

[0047] To make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below with reference to embodiments and drawings. The illustrative embodiments of the present invention and their descriptions are only used to explain the present invention and shall not be construed as limiting the present invention; it should be understood that although terms such as first and second may be used herein to describe various units, these units should not be limited by these terms. These terms are only used to distinguish one unit from another. For example, the first unit may be referred to as the second unit, and similarly, the second unit may be referred to as the first unit, without departing from the scope of the exemplary embodiments of the present invention.

[0048] Embodiment:

[0049] See Figure 1 As shown, the maskless lithography imaging system based on DMD provided in this embodiment may, but is not limited to, include: a light homogenizing module, an exposure module, and an imaging module; wherein, the light homogenizing module is used to collimate and homogenize the incident light emitted by the light source group 100, so as to ensure uniform illumination of the DMD target surface; and the exposure module is used to combine the exposure image uploaded by the host computer and the light emitted by the light homogenizing module to generate a digital mask pattern; finally, the imaging module is used to perform a reduction imaging process on the digital mask pattern; wherein, the specific working processes of the foregoing each module are as follows:

[0050] In specific applications, the light homogenizing module is used to receive the incident light emitted by the light source group 100, adjust the incident light into uniform spot light that meets the lithography conditions, and emit the uniform spot light to the exposure module; in this embodiment, the light homogenizing module mainly collimates and homogenizes the incident light (its collimation and homogenization modulation process will be elaborated in detail below) to generate uniform spot light suitable for the DMD array group 20; wherein, for example, the light source group 100 may, but is not limited to, adopt an LED light source group, and for example, the LED light source group emits near-ultraviolet light with a wavelength of 400 - 420 nm; of course, the light emitting mode and wavelength of the light source group can be specifically set according to actual use, and are not limited to the foregoing examples here.

[0051] After the collimation, homogenization, and modulation of the incident light are completed, the uniformly illuminated spot light obtained through modulation can be emitted to the exposure module, so that the exposure module can be used to perform digital mask modulation. Specifically, in this embodiment, the exposure module may include, but is not limited to, a DMD array group 20. The DMD array group 20 is configured to receive the exposure image and the uniformly illuminated spot light, and generate an exposure pattern light based on the exposure image and the uniformly illuminated spot light and emit it to the imaging module.

[0052] In specific implementation, the principle of the DMD array group 20 generating a digital mask pattern is as follows: The DMD (Digital Micromirror Device) array group is a two-dimensional array composed of a plurality of tiny mirrors, and each micromirror can be tilted independently to control the reflection direction of light. Each micromirror can deflect ±12° around the articulated skew axis. In practical applications, the +12° state corresponds to an "on" pixel, and the incident light can be reflected onto the screen to form a bright spot, while the -12° state corresponds to an "off" pixel, and the light will be reflected in other directions, presenting a dark spot on the screen. Therefore, the host computer transmits the exposure image into the pattern generation unit inside the DMD array group 20. The pattern generation unit controls the actions of each micromirror in the DMD array group 20 according to the transmitted exposure image information, so as to turn the required light into the imaging module. Further, the exposure image can be transmitted by the host computer to the DMD driver board (the pattern generation unit is integrated on the driver board). Then, the DMD driver board outputs corresponding electrical pulse signals. Then, according to the electrical pulse signals, the deflection angle of each micromirror is controlled, so as to determine the reflection angle of the uniformly illuminated spot light, and further generate the exposure pattern light, that is, the digital mask pattern.

[0053] In this way, by using the DMD digital micromirror, the modulation of the exposure light field is completed, the digital control of the exposure pattern is realized, and the digital mask pattern is obtained, which can avoid the problems of high cost and long development time in the traditional technology that requires a mask plate and its manufacturing equipment for mask lithography.

[0054] Therefore, based on the aforementioned DMD array group 20, after the exposure pattern light is generated, the imaging module can be used for lithography imaging, that is: the imaging module is configured to receive the exposure pattern light emitted by the DMD array group 20, and perform a reduction process on the exposure pattern light to obtain a reduced pattern light; finally, project the reduced pattern light onto the wafer; in this way, the lithography process of the exposure image can be completed.

[0055] Based on the foregoing description, the maskless lithography imaging system provided in this embodiment, compared with the traditional mask lithography technology based on a mask plate, uses a digital mask pattern, which does not require a mask plate and its manufacturing equipment. Based on this, not only can the mask manufacturing cost be greatly reduced, but also the mask development time can be reduced. In this way, the lithography efficiency can be improved.

[0056] In a possible design, the second aspect of this embodiment provides the detailed structures of the light homogenization module, the exposure module, and the imaging module in the first aspect of the embodiment.

[0057] First, a specific structure of the light homogenization module is provided:

[0058] See Figure 1 As shown, for example, the light homogenization module may include, but is not limited to: a light homogenization and collimation lens group 10, where the light homogenization and collimation lens group 10 is used to perform light collimation and homogenization processing on the incident light, so as to generate a uniform spot light that meets the lithography conditions after the light collimation and homogenization processing; in this way, it is equivalent to using the light homogenization and collimation lens group 10 to achieve the collimation and homogenization modulation of the illumination light field (i.e., the incident light), thereby ensuring uniform illumination of the DMD array group 20.

[0059] In specific implementation, one of the structures of the following disclosed light homogenization and collimation lens group 10 is:

[0060] Optionally, for example, the light homogenization and collimation lens group 10 may include, but is not limited to: a focusing lens, a collimating lens, a fly-eye compound eye lens, a diverging lens, and an exit lens; the working processes of the foregoing lenses are as follows:

[0061] The focusing lens is used to focus the incident light to obtain focused light and emit the focused light to the collimating lens; and the collimating lens is used to collimate the focused light to obtain collimated light and emit the collimated light to the fly-eye compound eye lens; where when the collimated light is incident on the fly-eye compound eye lens, the fly-eye compound eye lens can perform light homogenization processing on the collimated light to obtain uniform collimated light and emit the uniform collimated light to the diverging lens; finally, the diverging lens is used to adjust the light divergence angle of the uniform collimated light to obtain uniform spot light and emit the uniform spot light to the DMD array group 20 through the exit lens; at the same time, for example, the focusing lens may include, but is not limited to, a convex lens, and the diverging lens may include, but is not limited to, a concave lens; in this way, the focusing and diverging functions of the incident light can be achieved.

[0062] Based on the foregoing description, the collimation and homogenization processing of the illumination light field can be achieved through the foregoing focusing lens, collimating lens, fly-eye compound eye lens, diverging lens, and outgoing lens, so as to obtain uniform spot light suitable for the DMD array group 20.

[0063] Furthermore, to ensure that the generated uniform spot light meets the lithography conditions, a light inspection unit is also provided in this embodiment; wherein, the light inspection unit is used to perform light detection processing on the uniform spot light to obtain a light detection result, and the light inspection unit is also used to judge whether the uniform spot light meets the lithography conditions based on the light detection result, and output a light adjustment prompt message when it is detected that the uniform spot light does not meet the lithography conditions.

[0064] In this embodiment, for example, the light detection may include but is not limited to spot size detection, light intensity distribution detection, and light collimation detection; thus, the light detection result includes a spot detection result, a light intensity detection result, and a light collimation detection result; wherein, when the above three detection results all meet the corresponding spot standard, light intensity standard, and light collimation standard in lithography, it is determined that the uniform spot light emitted by the homogenization and collimation lens group 10 meets the lithography conditions and can enter the DMD array group 20 for digital modulation of the mask; if one or more of the above detection results do not meet the corresponding standards, a light adjustment prompt message needs to be output to remind the staff to adjust the light source, that is, to adjust the output power of the light source group 100 or the parameters of the homogenization and collimation lens group 10 (such as the distance between the lenses, etc.).

[0065] In this embodiment, for example, a spectrometer is used to detect the spot size, light intensity distribution, and light collimation (the collimation detection can be performed by detecting the divergence angle of the light beam, and then evaluating the collimation degree of the light based on the divergence angle), and then the detection result is output to the host computer to obtain the corresponding light detection result, and further judge whether the generated spot light meets the spot size during lithography, whether the light intensity reaches the exposure condition, and whether the light collimation degree meets the lithography requirements, and control the light inspection unit to output the corresponding prompt message when it does not meet the lithography conditions; of course, the corresponding numerical values of the above spot standard, light intensity standard, and light collimation standard can be preset, and different light detection instruments can also be selected according to actual use, which is not limited to the foregoing example here.

[0066] In addition, in this embodiment, refer to Figure 1As shown, a reflector 60 is provided on the light exit path of the homogenizing module (i.e., a reflector 60 is provided on the light exit path of the homogenizing and collimating lens group 10). Among them, the reflector 60 is used to reflect the uniformly distributed spot light emitted by the homogenizing module into the DMD array group 20 in the exposure module, so as to combine with the exposure image transmitted by the host computer to perform digital modulation of the mask image. That is, the host computer transmits the exposure image into the pattern generation unit in the DMD array group 20. Then, the DMD array group 20 switches its actions according to the transmitted exposure image information, controls the deflection of each effective micromirror unit inside by ±12°, so as to control the reflection of the uniformly distributed spot light to express the exposure image. Finally, the uniformly exposed pattern spot (i.e., the exposure pattern light) is reflected by the DMD and turned into the imaging module.

[0067] Thus, after the detailed structure of the homogenizing module is described, the structure of the imaging module is described as follows:

[0068] In a specific implementation, for example, the imaging module may include, but is not limited to, a tube lens 30 and a microscope group 40.

[0069] Among them, the tube lens 30 is used to receive the exposure pattern light emitted by the DMD array group 20, perform a first reduction process on the exposure pattern light to obtain the first reduced pattern light; then, perform a quasi-parallel process on the first reduced pattern light to obtain the processed reduced pattern light, and emit the processed reduced pattern light to the microscope group 40; and the microscope group 40 is used to perform a second reduction process on the processed reduced pattern light to obtain the reduced pattern light, and project the reduced pattern light onto the wafer 50; thus, maskless lithography imaging of the exposure image can be completed.

[0070] Based on the foregoing description of the tube lens 30, the exposure pattern light in this embodiment is first focused at the first focal point by the tube lens 30 to perform a one-to-one reduction of the image for the first pattern reduction, that is, the tube lens 30 is used to focus the exposure pattern light at the target focal point for the first reduction process (the target focal point includes the first focal point of the tube lens) to obtain the first reduced pattern light; then, a quasi-parallel process is performed in the tube lens 30, that is, according to the structural characteristics of the tube lens, the light reflected by the action switching of the DMD array group 20 is focused at a point for the quasi-parallel process, so as to ensure that the light can propagate in a consistent direction in the subsequent optical system, thereby improving the clarity and resolution of the image; thus, based on the tube lens 30, the first reduction and clarity adjustment of the lithography pattern can be completed.

[0071] Meanwhile, in this embodiment, in order to ensure the clarity of the lithography pattern, a beam splitter 70, a CCD camera group 80, and a controller 90 are further provided, so as to perform depth-of-field focusing by means of the beam splitter 70 and the CCD camera group 80.

[0072] Specifically, the beam splitter 70 is used to perform optical path splitting on the processed demagnified graphic light rays emitted by the tube lens 30 to obtain multiple paths of demagnified graphic light rays, and the multiple paths of demagnified graphic light rays are emitted to the CCD camera group 80 through lenses (in this embodiment, each path of demagnified graphic light ray corresponds to a lens); then, the CCD camera group 80 can be used to receive the light rays, that is, each CCD camera in the CCD camera group 80 receives a path of demagnified graphic light ray respectively, generates an imaging image corresponding to the optical path, and transmits the corresponding imaging image to the controller 90; finally, the controller 90 is used to perform image comparison processing on the imaging images of each optical path and a preset exposure image (transmitted from the host computer to the controller) to obtain the imaging clarity of the processed demagnified graphic light rays, and output a prompt message for adjusting the parameters of the light homogenization module when it is detected that the imaging clarity does not meet the preset conditions; based on this, it is equivalent that the controller 90 controls the CCD camera group 80 to perform depth-of-field focusing through the beam splitter. The beam splitter separates the light rays emitted by the tube lens 30, each path of light passes through a lens at a different focal plane, the CDD camera group 80 receives each path of light, determines the depth-of-field range, and compares the images captured by the CDD at different focal planes with the exposure image to judge the clarity of the image edge; based on this, the CCD camera group 80 can be used to detect the imaging clarity, so as to ensure the clarity of the subsequent lithography pattern.

[0073] Of course, in this embodiment, the controller 90 fuses the images output by all CCD cameras, and performs image comparison on the fused image and the exposure image to obtain the imaging clarity of the image; for example, the fused image and the exposure image can be visually displayed for the staff to view; then, the staff can input the corresponding imaging clarity; in this way, when the controller responds to the human-computer interaction operation, the imaging clarity of the processed demagnified graphic light rays can be obtained, and based on this, it can be judged whether the imaging clarity meets the preset conditions; when the imaging clarity does not meet the preset conditions, a prompt message for adjusting the parameters of the light homogenization module is output to remind the staff to adjust the power of the light source group 100 or the parameters of the light homogenization and collimation lens group 10.

[0074] In this way, after the exposure graphic light rays are demagnified once by the tube lens 30, they can be emitted to the microscope group 40 for secondary demagnification; then, the microscope group 40 projects the demagnified graphic light rays onto the wafer 50 to complete the exposure.

[0075] In addition, in this embodiment, to ensure the accuracy of graphic demagnification, a graphic demagnification detection unit is further provided. The graphic demagnification detection unit is configured to perform demagnification multiple detection processing on the graphic light rays after the first demagnification and the demagnified graphic light rays, obtain a demagnification multiple detection result, and output a prompt message for adjusting the imaging component parameters when it is determined that the demagnification multiple detection result does not meet the preset demagnification condition. In this way, if the demagnification in the tube lens 30 and / or the microscope group 40 does not reach the corresponding demagnification multiple, it is necessary to adjust the focus of the tube lens 30 and the eyepiece multiple of the microscope group 40 to ensure the accuracy of graphic demagnification.

[0076] Optionally, for example, the graphic demagnification detection unit can, but is not limited to, capturing graphic images using an optical or electron microscope to complete the demagnification detection of the graphics.

[0077] Through the foregoing description, the present invention realizes the homogenization modulation of the illumination light field through the homogenizing and collimating lens group, thereby ensuring uniform illumination of the DMD target surface. Then, through the DMD digital micromirror, the modulation of the exposure light field is completed to realize the digital control of the exposure pattern. Finally, on the basis of this exposure system, the combination of the tube lens and the microscope group is used to simply realize the demagnification of the digital mask pattern. In this way, compared with the traditional technology, the present invention can greatly reduce the mask production cost and development time by using digital mask patterns. At the same time, since there is no need for a mask plate during lithography, a mercury lamp can be not used as the light source (traditional mask plate lithography requires a mercury lamp as the light source). Based on this, the problem of short mercury lamp life in traditional lithography technology can be avoided. Therefore, the present invention is very suitable for large-scale application and promotion in the field of lithography technology.

[0078] As Figure 2 shown, in the second aspect of this embodiment, a maskless lithography imaging method based on DMD is provided, which is implemented based on the maskless lithography imaging system described in the first aspect of the embodiment. The running steps of this imaging method can, but are not limited to, the following steps S1 to S3.

[0079] S1. The homogenizing module receives the incident light rays emitted by the light source group, adjusts the incident light rays into uniform spot light rays that meet the lithography conditions, and emits the uniform spot light rays to the DMD array group in the exposure module.

[0080] S2. The DMD array group receives the exposure image and the uniform spot light rays, generates exposure graphic light rays based on the exposure image and the uniform spot light rays, and emits them to the imaging module.

[0081] S3. The imaging module receives the exposure pattern light emitted by the DMD array group, performs a reduction process on the exposure pattern light to obtain the reduced pattern light, and projects the reduced pattern light onto the wafer to complete the lithography process of the exposure image.

[0082] For the working process, working details and technical effects of the imaging method provided in this embodiment, reference can be made to the first aspect of the embodiment, which will not be elaborated here.

[0083] In the third aspect of this embodiment, a maskless lithography imaging based on DMD is provided. Taking the device as an electronic device as an example, it includes: a memory, a processor, and a transceiver that are communicatively connected in sequence. Among them, the memory is used to store computer programs, the transceiver is used to send and receive messages, and the processor is used to read the computer programs and execute the maskless lithography imaging method based on DMD as described in the second aspect of the embodiment.

[0084] Specifically, the memory may include, but is not limited to, random access memory (RAM), read only memory (ROM), flash memory, first input first output (FIFO), and / or first in last out (FILO), etc.; specifically, the processor may include one or more processing cores, such as a 4-core processor, an 8-core processor, etc. The processor can be implemented in at least one hardware form of DSP (Digital Signal Processing), FPGA (Field-Programmable Gate Array), and PLA (Programmable Logic Array). At the same time, the processor may also include a main processor and a coprocessor. The main processor is a processor used to process data in the wake state, also known as the CPU (Central Processing Unit); the coprocessor is a low-power processor used to process data in the standby state.

[0085] In some embodiments, the processor may integrate a GPU (Graphics Processing Unit). The GPU is responsible for rendering and drawing the content to be displayed on the display screen. For example, the processor may be, but is not limited to, a microprocessor of the STM32F105 series, a reduced instruction set computer (RISC) microprocessor, a processor with an X86 architecture, or a processor integrated with an embedded neural-network processing unit (NPU). The transceiver may be, but is not limited to, a Wi-Fi wireless transceiver, a Bluetooth wireless transceiver, a General Packet Radio Service (GPRS) wireless transceiver, a ZigBee (low-power local area network protocol based on the IEEE802.15.4 standard) wireless transceiver, a 3G transceiver, a 4G transceiver, and / or a 5G transceiver, etc. In addition, the device may also include, but is not limited to, a power module, a display screen, and other necessary components.

[0086] For the working process, working details, and technical effects of the electronic device provided in this embodiment, reference may be made to the first aspect of the embodiment, which will not be elaborated here.

[0087] In the fourth aspect of this embodiment, a storage medium storing instructions for the DMD-based maskless lithography imaging method described in the second aspect of the embodiment is provided. That is, instructions are stored on the storage medium. When the instructions run on a computer, the DMD-based maskless lithography imaging method described in the second aspect of the embodiment is executed.

[0088] Among them, the storage medium refers to a carrier for storing data, and may be, but is not limited to, including a floppy disk, an optical disc, a hard disk, a flash memory, a USB flash drive, and / or a Memory Stick, etc. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices.

[0089] For the working process, working details, and technical effects of the storage medium provided in this embodiment, reference may be made to the first aspect of the embodiment, which will not be elaborated here.

[0090] In the fifth aspect of this embodiment, a computer program product containing instructions is provided. When the instructions run on a computer, the computer is caused to execute the DMD-based maskless lithography imaging method described in the second aspect of the embodiment. Among them, the computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices.

[0091] The specific embodiments described above further elaborate on the objective, technical solution and beneficial effects of the present invention. It should be understood that the above description is only the specific embodiments of the present invention and is not used to limit the protection scope of the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A maskless lithography imaging system based on DMD, characterized in that, Comprising: A light homogenizing module, wherein the light homogenizing module is used to receive the incident light emitted by the light source group, adjust the incident light into uniform spot light conforming to the lithography conditions, and emit the uniform spot light to the exposure module; An exposure module, the exposure module includes a DMD array group, wherein the DMD array group is used to receive the exposure image and the uniform spot light, and generate exposure pattern light based on the exposure image and the uniform spot light and emit it to the imaging module; An imaging module, which is used to receive the exposure pattern light emitted by the DMD array group and perform a reduction process on the exposure pattern light to obtain reduced pattern light; The imaging module is further used to project the reduced pattern light onto the wafer to complete the lithography process of the exposure image.

2. The maskless lithography imaging system based on DMD according to claim 1, wherein The light homogenizing module includes: a light homogenizing and collimating lens group, wherein the light homogenizing and collimating lens group is used to perform light collimation and homogenization processing on the incident light, so as to generate uniform spot light conforming to the lithography conditions after the light collimation and homogenization processing.

3. The maskless lithography imaging system based on DMD according to claim 2, characterized in that The light homogenizing and collimating lens group includes: a focusing lens, a collimating lens, a fly-eye compound eye lens, a diverging lens, and an exit lens; The focusing lens is used to perform focusing processing on the incident light to obtain focused light and emit the focused light to the collimating lens; The collimating lens is used to perform light collimation processing on the focused light to obtain collimated light and emit the collimated light to the fly-eye compound eye lens; The fly-eye compound eye lens is used to perform light homogenization processing on the collimated light to obtain uniform collimated light and emit the uniform collimated light to the diverging lens; The diverging lens is used to adjust the light divergence angle of the uniform collimated light to obtain uniform spot light, and emit the uniform spot light to the DMD array group through the exit lens.

4. The maskless lithography imaging system based on DMD according to claim 2, wherein, The light homogenizing module further includes a light inspection unit, wherein the light inspection unit is used to perform light detection processing on the uniform spot light to obtain a light detection result, and the light detection includes spot size detection, light intensity distribution detection, and light collimation detection; The light inspection unit is further used to judge whether the uniform spot light conforms to the lithography conditions based on the light detection result, and output a light adjustment prompt message when it is detected that the uniform spot light does not conform to the lithography conditions.

5. A maskless lithography imaging system based on DMD according to claim 1, wherein, A reflecting mirror is arranged on the light exit path of the light homogenizing module, wherein the reflecting mirror is used to reflect the uniform spot light emitted by the light homogenizing module into the exposure module.

6. The maskless lithography imaging system based on DMD according to claim 1, wherein The imaging module includes: a tube lens and a microscope group; The tube lens is used to receive the exposure pattern light emitted by the DMD array group and perform a first reduction process on the exposure pattern light to obtain first-reduced pattern light; The tube lens is further used to perform a quasi-parallel process on the first-reduced pattern light to obtain processed reduced pattern light, and emit the processed reduced pattern light to the microscope group; The microscope group is used to perform a second reduction process on the processed reduced pattern light to obtain the reduced pattern light, and project the reduced pattern light onto the wafer.

7. The maskless lithography imaging system based on DMD according to claim 6, wherein The tube lens is used to focus the exposure pattern light at a target focus for primary reduction processing to obtain the primary reduced pattern light, where the target focus includes the first focal point of the tube lens.

8. The maskless lithography imaging system based on DMD according to claim 6, wherein, The imaging module further includes: a beam splitter, a CCD camera group, and a controller; The beam splitter is used to perform optical path splitting on the processed reduced pattern light emitted from the tube lens to obtain multiple paths of reduced pattern light, and output the multiple paths of reduced pattern light to the CCD camera group through lenses, where the reduced pattern light of each optical path respectively corresponds to a lens; The CCD camera group, where each CCD camera in the CCD camera group respectively receives a path of reduced pattern light, is used to generate an imaging image corresponding to the optical path, and transmit the corresponding imaging image to the controller; The controller is used to perform image comparison processing on the imaging images of each optical path and a preset exposure image to obtain the imaging clarity of the processed reduced pattern light, and output a prompt message for adjusting the parameters of the light homogenization module when it is detected that the imaging clarity does not meet the preset conditions.

9. The maskless lithography imaging system based on DMD according to claim 6, wherein The imaging module further includes: a pattern reduction detection unit, where the pattern reduction detection unit is used to perform reduction multiple detection processing on the primary reduced pattern light and the reduced pattern light to obtain a reduction multiple detection result; The pattern reduction detection unit is further used to output a prompt message for adjusting the parameters of the imaging component when it is determined that the reduction multiple detection result does not meet the preset reduction conditions.

10. A maskless lithography imaging method based on DMD, characterized in that, Implemented based on the DMD-based maskless lithography imaging system according to any one of claims 1 to 9, where the method includes: The light homogenization module receives the incident light emitted by the light source group, adjusts the incident light into uniform spot light that meets the lithography conditions, and outputs the uniform spot light to the DMD array group in the exposure module; The DMD array group receives the exposure image and the uniform spot light, generates exposure pattern light based on the exposure image and the uniform spot light, and outputs it to the imaging module; The imaging module receives the exposure pattern light emitted by the DMD array group, reduces the exposure pattern light to obtain the reduced pattern light, and projects the reduced pattern light onto the wafer to complete the lithography process of the exposure image.

Images