Method and system for regenerating a mask substrate

Abstract

The application provides a mask substrate regeneration method and system, which adopts a method of laser film removing and then laser polishing to remove mask materials such as photoresist, metal film, metal compound film and the like on the mask substrate, and the whole process is realized through laser technology, without intervention of wet process, so that the problems of high cost, long process time and environmental pollution caused by the wet process in the existing mask substrate regeneration method can be solved. Meanwhile, the surface roughness is detected in real time during the removal of the mask material, and the laser surface treatment process is adjusted based on the online real-time detection result, so that the yield of the regenerated mask substrate obtained by recycling is improved, and the production cost is reduced.

Description

[0001] This application is a divisional application of the parent application with application number CN202310720627.3, application date June 16, 2023, and invention title "Method and System for Manufacturing a Mask". Technical Field

[0002] This invention relates to the field of semiconductor device manufacturing technology, and in particular to a method and system for manufacturing a photomask. Background Technology

[0003] With the development of innovative technologies such as Artificial Intelligence (AI), 5G, big data, AIoT, and autonomous driving, the reduction of device feature sizes in microprocessors (CPUs) and dynamic random access memory (DRAM) has accelerated and deviated from Moore's Law, which has inadvertently increased the difficulty of semiconductor device fabrication.

[0004] Currently, photolithography is the most complex and challenging process in semiconductor manufacturing. Its main principle is to transfer the pattern on a photomask onto a substrate using a photoresist (also known as a photoresist) under illumination. Furthermore, as semiconductor devices become increasingly integrated and their feature sizes shrink, the number of photomasks required for fabrication also increases. For example, fabricating a single chip at the 10nm process node requires over eighty photomasks. Clearly, reducing the manufacturing cost of photomasks can lower the overall production cost of semiconductor devices.

[0005] However, the mainstream manufacturing technology for blank photomasks is planar magnetron sputtering deposition. Due to the interaction of the orthogonal electromagnetic field with the sputtered ions in this deposition technology, the sputtering target will experience uneven erosion during sputtering, resulting in a generally low utilization rate of the sputtering target, only about 30%, which also affects the manufacturing yield of blank photomasks. In recent years, improvements in magnetron sputtering equipment have increased the target utilization rate to about 50%. In addition, after the target atoms are ejected by argon ions, about 1 / 6 of the sputtered atoms will deposit on the inner wall or support of the vacuum chamber, increasing the cost of cleaning the vacuum equipment and downtime. For these reasons, the manufacturing cost of blank photomasks remains high, and the yield is difficult to improve.

[0006] In addition, the structure of a blank photomask generally includes a photomask substrate (e.g., a glass substrate), a photomask material layer (such as a chromium film or other light-shielding film) deposited on the photomask substrate, and photoresist coated on the photomask material layer. Currently, the process of further processing a blank photomask into a photomask with the desired patterns and lines typically includes: exposing the photoresist of the blank photomask to a laser or electron beam, followed by development to transfer the desired pattern (e.g., circuit patterns) into the photoresist; then, using the photoresist as a mask, further etching the photomask material layer to remove the portion not covered by the photoresist; after etching, cleaning away the remaining photoresist; finally, the remaining photomask material layer forms the desired pattern and lines on the photomask substrate of the blank photomask, thus creating a photomask with the desired pattern and lines for use by downstream chip manufacturers.

[0007] Therefore, how to simplify the mask manufacturing process, improve manufacturing efficiency and yield, and reduce mask manufacturing costs has become one of the technical problems that urgently need to be solved by those skilled in the art. Summary of the Invention

[0008] The purpose of this invention is to provide a method and system for manufacturing photomasks, which can simplify the manufacturing process of photomasks, reduce the manufacturing cost of photomasks, and improve the manufacturing yield of blank photomasks.

[0009] To achieve the above objectives, the present invention provides a method for manufacturing a photomask, comprising the following steps:

[0010] S1, pulsed laser deposition is performed on a mask substrate using a pulsed laser on a process machine to form the required mask material layer on the mask substrate, thereby obtaining a blank mask.

[0011] S2, the pulsed laser is further used on the process machine to perform laser direct writing on the mask material layer to form the desired pattern in the mask material layer, thereby obtaining a mask.

[0012] Optionally, step S1 includes repeatedly executing the following sub-steps:

[0013] S11, The pulsed laser is used on the process machine to perform pulsed laser deposition on the mask substrate to obtain a blank mask with a corresponding mask material layer;

[0014] S12, Detect whether the performance of the blank mask meets the target;

[0015] S13, when the performance of the blank mask is found to be substandard, a corresponding laser surface treatment method is selected according to the detection result, and the blank mask is subjected to laser surface treatment on the process machine to repair the surface of the mask material layer, or to remove the mask material layer and repair the surface of the mask substrate.

[0016] Optionally, before performing step S1, step S0 is further included, in which a mask to be discarded is provided, and the mask to be discarded is subjected to laser surface treatment on the process machine to remove the film layer on the mask substrate of the mask to be discarded, thereby obtaining the mask substrate.

[0017] Optionally, the laser surface treatment method includes one of the following three methods:

[0018] The first method involves using a first laser to perform laser film removal in order to remove a film layer of a corresponding thickness from the mask substrate;

[0019] The second method involves using a second laser, different from the first laser, to perform laser polishing on the surface of the film layer on the mask substrate.

[0020] The third method involves first using the first laser for laser film removal, and then using the second laser for laser polishing.

[0021] Wherein, the first laser or the second laser is the pulsed laser.

[0022] Optionally, the pulsed laser can be either the first laser or the second laser.

[0023] Optionally, during the laser surface treatment process, the surface morphology of the film layer on the mask substrate is inspected online on the process machine, and the process parameters during the laser surface treatment process are adjusted online based on the surface morphology inspection results.

[0024] Optionally, in step S12, detecting whether the performance of the basic structure of the blank mask meets the target includes: detecting whether at least one of the following performance indicators—the thickness of the mask material layer, the surface flatness, and the transmittance and reflectance of the blank mask—meets the target.

[0025] Optionally, if the performance of the blank mask is found to be substandard in step S12, the process parameters of pulsed laser deposition are adjusted so that after the laser surface treatment in step S13 is completed and step S11 needs to be executed again, the corresponding pulsed laser deposition process can be performed on the blank mask after laser surface treatment in step S11 based on the adjusted parameters.

[0026] Based on the same inventive concept, the present invention also provides a mask manufacturing system, which includes:

[0027] A pulsed laser deposition apparatus is used to perform pulsed laser deposition on a mask substrate using a pulsed laser on the process equipment to form a required mask material layer on the mask substrate and obtain a blank mask.

[0028] A pulsed laser direct writing apparatus is used to further employ the pulsed laser on the process machine to perform laser direct writing on the mask material layer, so as to form the desired pattern in the mask material layer and obtain a mask.

[0029] The system's main control unit is coupled to the pulsed laser deposition device and the pulsed laser direct writing device, and is used to control the coordinated operation of the pulsed laser deposition device and the pulsed laser direct writing device.

[0030] Optionally, the manufacturing system also includes components integrated into the process equipment:

[0031] A detection device is used to detect whether the performance of the blank mask meets the target.

[0032] A laser surface treatment apparatus is used to perform laser surface treatment on the blank mask on the process machine to trim the surface of the mask material layer, or to remove the mask material layer and trim the surface of the mask substrate.

[0033] The system's main control device is also coupled to the laser surface treatment device and the detection device. When the detection device detects that the performance of the blank mask does not meet the standard, it controls the pulsed laser deposition device, the detection device, and the laser surface treatment device to work in coordination, so that the mask substrate circulates in the pulsed laser deposition device, the detection device, and the laser surface treatment device until the performance of the blank mask reaches the target.

[0034] Optionally, the laser surface treatment apparatus is further configured to initially perform laser surface treatment on the mask to be discarded on the process machine using the pulsed laser or another laser to remove the film layer on the mask substrate of the mask to be discarded, thereby obtaining the mask substrate required in the pulsed laser deposition apparatus.

[0035] Optionally, the laser surface treatment method includes one of the following three methods:

[0036] The first method involves using a first laser to perform laser film removal in order to remove a film layer of a corresponding thickness from the mask substrate;

[0037] The second method involves using a second laser, different from the first laser, to perform laser polishing on the surface of the film layer on the mask substrate.

[0038] The third method involves first using the first laser for laser film removal, and then using the second laser for laser polishing.

[0039] Wherein, the first laser or the second laser is the pulsed laser.

[0040] Optionally, the first laser or the second laser is transmitted to the laser surface treatment device, the pulsed laser deposition device, and the pulsed laser direct writing device via a shutter, a quarter-wave plate, a polarizer, a first beam splitter, and a second beam splitter arranged sequentially along the optical path.

[0041] Optionally, the laser surface treatment device includes a first beam expanding mechanism, a focusing mechanism, and a first scanning focusing mechanism; the first beam expanding mechanism is used to increase the beam size of the received first laser or second laser before outputting it; the focusing mechanism is used to focus the laser emitted by the beam expanding mechanism; the first scanning focusing mechanism is used to control the laser emitted by the focusing mechanism to be focused onto the surface of the mask substrate in the film removal chamber or the film layer surface on the mask substrate, thereby realizing laser scanning of the mask substrate.

[0042] Optionally, the manufacturing system further includes a first laser, a second laser, and a beam combining mechanism. The first laser is used to provide the first laser beam, the second laser is used to provide the second laser beam, and the beam combining mechanism is used to receive the first laser beam and the second laser beam in a time-division manner and emit the received laser beams at the same angle to the beam expanding mechanism.

[0043] Optionally, the detection device is used to detect whether at least one of the following performance indicators—thickness of the mask material layer, surface flatness, and transmittance and reflectance of the blank mask—meets the target.

[0044] Optionally, the manufacturing system further includes a first transition chamber, a robotic arm transfer device, and a second transition chamber. The first transition chamber is disposed between the chamber of the laser surface treatment device and the deposition chamber, and the second transition chamber is disposed between the deposition chamber and the chamber of the laser direct writing device. The robotic arm transfer device is used to transfer the mask substrate between the chamber of the laser surface treatment device, the first transition chamber, the deposition chamber, the second transition chamber, and the chamber of the laser direct writing device.

[0045] Optionally, the pulsed laser deposition apparatus includes a first focusing mechanism, a deposition chamber, and a stage and a target disposed in the deposition chamber. The first focusing mechanism is used to focus the corresponding laser beam onto the target, and the stage is used to support the mask substrate.

[0046] Optionally, the pulsed laser direct writing device includes a reflector, a second beam expander, a first dichroic prism, a second dichroic prism, and a second scanning focusing mechanism arranged sequentially along the optical path.

[0047] Optionally, the pulsed laser direct writing device further includes an illumination source, a second focusing mechanism, and a detector. The illumination source is used to provide illumination light to the first dichroic prism, and the second focusing mechanism is used to focus a portion of the laser light at the second dichroic prism into the detector.

[0048] Compared with the prior art, the technical solution of the present invention has at least one of the following beneficial effects:

[0049] 1. This invention utilizes pulsed laser deposition on the same process machine to manufacture blank photomasks, and further utilizes pulsed laser generated by the same laser to perform laser direct writing on the blank photomasks to obtain photomasks with the desired pattern. This invention enables automated manufacturing of photomasks, and features a simple process, low manufacturing cost, high production efficiency, stable photomask performance, high yield, low process machine equipment cost, and high integration.

[0050] 2. In the process of manufacturing blank photomasks, the cyclic execution of steps such as pulsed laser deposition (PLD), inspection, and laser surface treatment (laser removal or laser removal followed by laser polishing) can ensure that the performance of the final blank photomask meets the target through automated means, thereby improving the manufacturing yield of the photomask.

[0051] 3. By performing laser surface treatment on discarded photomasks, the photomask substrate can be recycled, and blank photomasks and photomasks can be manufactured based on the recycled photomask substrate, thereby reducing the manufacturing cost of photomasks.

[0052] 4. When the performance of the blank mask is found to be substandard, the parameters of the pulsed laser deposition process are adjusted. Based on the adjusted parameters, the corresponding pulsed laser deposition process is performed again on the blank mask after laser surface treatment. The pulsed laser deposition process has a high target utilization rate and can improve the manufacturing efficiency of the blank mask, thereby improving the overall manufacturing efficiency of the mask.

[0053] 5. From the recycling and regeneration of waste photomasks to the manufacturing of new blank photomasks, and then to the generation of photomask patterns, the entire process is achieved through laser technology, without the need for wet processes. Therefore, it can solve the problems of high cost, long processing time, and environmental pollution caused by wet processes in existing photomask substrate recycling methods and blank photomask manufacturing methods. Attached Figure Description

[0054] Those skilled in the art will understand that the accompanying drawings are provided to better understand the invention and do not constitute any limitation on the scope of the invention. Wherein:

[0055] Figure 1 This is a flowchart of the mask manufacturing method according to the first embodiment of the present invention.

[0056] Figure 2 This is a cross-sectional structural diagram of the mask manufacturing method according to the first embodiment of the present invention.

[0057] Figure 3 This is a schematic cross-sectional view of another type of mask manufactured in the mask manufacturing method of the second embodiment of the present invention.

[0058] Figure 4 This is a schematic diagram of the architecture of the mask manufacturing system according to the first embodiment of the present invention.

[0059] Figure 5 This is a schematic diagram of the specific structure of the mask manufacturing system according to the first embodiment of the present invention.

[0060] Figure 6 This is a flowchart of the mask manufacturing method according to the second embodiment of the present invention.

[0061] Figure 7 This is a schematic diagram of the architecture of the mask manufacturing system according to the second embodiment of the present invention.

[0062] Figures 8 to 10 This is a schematic diagram of the specific structure of the mask manufacturing system according to the second embodiment of the present invention.

[0063] Figure 11 This is a flowchart of the mask manufacturing method according to the third embodiment of the present invention.

[0064] Figure 12 This is a simplified flowchart of the mask manufacturing method according to the third embodiment of the present invention, where steps S0 and S13 employ essentially the same process.

[0065] The reference numerals in each of the attached figures are as follows:

[0066] 101-Mask substrate; 102-Phase shift film; 103-Back anti-reflection film; 104-Light-shielding film; 105-Anti-reflection film; 106-Mask material layer; 107-Desired pattern;

[0067] 200 - Pulsed laser deposition apparatus; 201 - Laser surface treatment apparatus; 202 - System control unit; 203 - Detection device; 204 - Pulsed laser direct writing apparatus;

[0068] 1. 41-Laser; 2-Shutter; 3-Quarter-wave plate; 4-Polarizer; 5-First beam splitter; 6-First beam expander; 7a-Focusing mechanism; 7b-First scanning focusing mechanism; 8-Laser control mechanism; 9. 18-Light transmission window; 10-Sample; 11-Laser surface treatment chamber; 12-First transition chamber; 12a, 50a-Robot transfer device; 14-Stage; 15-Target material; 16-Second beam splitter; 17-First focusing mechanism; 19-Deposition chamber;

[0069] 20-Reflector; 21-Second beam expander; 22-Illumination source; 23-First dichroic prism; 24-Second dichroic prism; 25-Second scanning and focusing mechanism; 26-Second focusing mechanism; 27-Detector; 28-Stage; 29-Laser direct writing chamber;

[0070] 30-Surface morphology detection unit; 31-Signal processor; 32-Signal receiver; 33-Scanning light source; 34-Scanning drive cantilever; 35-Probe; 40-Band combining mechanism; 42, 43-Reflectors; 50-Second transition chamber. Detailed Implementation

[0071] In the following description, numerous specific details are set forth in order to provide a more thorough understanding of the invention. However, it will be apparent to those skilled in the art that the invention may be practiced without one or more of these details. In other instances, certain technical features well-known in the art have not been described in order to avoid confusion with the invention. It should be understood that the invention can be embodied in various forms and should not be construed as limited to the embodiments set forth herein. Rather, providing these embodiments will make the disclosure thorough and complete, and will fully convey the scope of the invention to those skilled in the art. The same reference numerals denote the same elements throughout. It should be understood that when an element is referred to as "connected to" or "coupled to" other elements, it may be directly connected to other elements, or there may be intervening elements. Conversely, when an element is referred to as "directly connected to" other elements, there are no intervening elements. As used herein, the singular forms "a," "an," and "the" are also intended to include the plural forms, unless the context clearly indicates otherwise. It should also be understood that the term "comprising" is used to identify the presence of features, steps, operations, elements, and / or components, but does not exclude the presence or addition of one or more other features, steps, operations, elements, components, and / or groups. When used herein, the term "and / or" includes any and all combinations of the associated listed items.

[0072] The technical solution proposed by the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. The advantages and features of the present invention will become clearer from the following description. It should be noted that the drawings are all in a very simplified form and use non-precise proportions, and are only used to facilitate and clarify the illustration of the embodiments of the present invention.

[0073] First Embodiment

[0074] Please refer to Figure 1 An embodiment of the present invention provides a method for manufacturing a photomask, which includes the following steps:

[0075] S1, pulsed laser deposition is performed on a mask substrate using a pulsed laser on a process machine to form the required mask material layer on the mask substrate, thereby obtaining a blank mask.

[0076] S2, the pulsed laser is further used on the process machine to perform laser direct writing on the mask material layer to form the desired pattern in the mask material layer, thereby obtaining a mask.

[0077] Please combine Figure 2 In step (A), in step S1, firstly, a corresponding mask substrate 101 is provided to the process equipment. This mask substrate 101 can be any suitable substrate with a clean and flat surface, such as any one of a quartz substrate, a soda lime substrate, and a borosilicate substrate. Next, please refer to... Figure 2 (B) and (C) in the middle and Figure 5 A laser is used on the process equipment to generate pulsed laser light, and then pulsed laser deposition (PLD) of the corresponding material is performed on the mask substrate 101 to form a mask material layer 106 of the required thickness and material. The desired blank mask is thus obtained.

[0078] In this regard, please combine Figure 2 (B) and (C) in the middle and Figure 5 The specific principle of pulsed laser deposition is as follows: After being transmitted and focused by the first focusing mechanism 17 such as a convex lens, the pulsed laser strikes the target 15 in the deposition chamber 19. Then, under the action of the pulsed laser, plasma is generated on the surface of the target 15. The plasma expands and emits in a directional and localized manner onto the sample 10 (i.e., Figure 2 A thin film (i.e., a newly deposited mask material layer) 106 is deposited on a mask substrate 101 or a blank mask consisting of a mask substrate 101 and a mask material layer 106 above it. In this step, depending on the target material 15 and the process parameters, the deposited mask material layer 106 can be a single-layer film structure such as metal, or a structure composed of multiple stacked films of different materials. The pulsed laser can be selected according to the light absorption characteristics of the mask material layer to be deposited, such as any suitable laser such as a ruby ​​laser, CO2 laser, ultraviolet laser, Nd glass laser, or excimer laser. In addition, the pulse width of the pulsed laser can be any suitable level such as femtosecond, picosecond, nanosecond, or microsecond, and correspondingly, the pulsed laser can be called a femtosecond laser, picosecond laser, nanosecond laser, or microsecond laser.

[0079] Since pulsed laser deposition is used to deposit the mask material layer 106 in this step, it has the following advantages: a. It is easy to obtain multi-component thin films with the desired stoichiometry, i.e., it has good compositional properties; b. It has a high deposition rate, short process cycle, low temperature requirements on the mask substrate 101, and uniform thin films; c. Process parameters can be adjusted arbitrarily, and there are no restrictions on the type of target material; d. It is easy to clean and can prepare a variety of thin film materials; e. It has a rapid reaction and fast growth, and a film of about 1 μm can usually be obtained in one hour, which can improve the utilization rate of the target material.

[0080] As an example, please combine further Figure 2In step (B), the mask material layer 106 deposited by pulsed laser deposition process includes a back antireflection film 103, a light-shielding film 104, and an antireflection film 105 stacked sequentially on the mask substrate 101 from bottom to top. The back antireflection film 103, the light-shielding film 104, and the antireflection film 105 are all formed based on the same target material. The difference lies in the reaction gas introduced during the deposition of the back antireflection film 103, the light-shielding film 104, and the antireflection film 105. For example, the back antireflection film 103, the light-shielding film 104, and the antireflection film 105 are all formed based on the Cr target material. During the deposition of the light-shielding film 104, N2 is introduced to form CrN as the light-shielding film 104. During the deposition of the back antireflection film 103 and the antireflection film 105, at least one of N2, O2, CO, or CO2 is introduced to form at least one of CrO, CrON, and CrCON as the back antireflection film 103 and the antireflection film 105.

[0081] As another example, please combine further Figure 3 The mask material layer 106 deposited using pulsed laser deposition in this step includes a phase shift film 102, a back antireflection film 103, a light-shielding film 104, and an antireflection film 105, which are sequentially stacked on the mask substrate 101 from bottom to top. The material of the phase shift film 102 may include at least one of Cr (chromium) compounds (e.g., chromium oxides, chromium nitrides, or chromium oxynitrides), MoSi, and MoSi compounds (e.g., MoSiON, MoSiCON, MoSiN, MoSiCN, or MoSiCO).

[0082] Please combine Figure 2 In step S2, the mask material layer 106 is laser-written on the same process machine using the same pulsed laser generated by the same laser used in step S1.

[0083] The specific principle of laser direct writing in this step is as follows: the corresponding pulsed laser is transmitted and focused by optical elements such as a reflector and a convex lens and then hits the sample 10 in the chamber 29. By controlling the pulsed laser to travel and stay along a specific path on the mask material layer 106, the pulsed laser can directly ablate the mask material layer 106 at a specific position, thereby forming the desired pattern 107 in the mask material layer 106, thus obtaining the mask.

[0084] In this step, the desired pattern 107 is formed in the mask material layer 106 by laser direct writing, which can eliminate the processes of coating, exposure, development, etching and resist removal required in the prior art from blank mask to mask, thus simplifying the process, improving efficiency and reducing costs.

[0085] It should be understood that the pulse width, wavelength, power and other parameters of the pulsed laser selected in this embodiment can be fixed to meet the requirements of both pulsed laser deposition and laser direct writing processes, or they can be adjustable to adapt to the sequence of pulsed laser deposition and laser direct writing processes.

[0086] For example, when the mask material layer 106 is composed of multiple layers of different materials stacked together, the parameters of the pulsed laser during the pulsed laser deposition process can be set according to the distance between the film layer and the surface of the mask substrate 101 and the material properties of the film layer. At least one parameter of the pulsed laser will be different when different film layers are deposited. Furthermore, the parameters of the pulsed laser during the laser direct writing process can be set according to the distance between the film layer and the surface of the mask substrate 101 and the material properties of the film layer. At least one parameter of the pulsed laser will be different when different film layers are laser direct written. As an example, as the depth of laser direct writing increases, the power of the pulsed laser decreases and the scanning step size decreases. This allows for rapid deepening of the ablation depth in the early stages of laser direct writing to improve laser direct writing efficiency, while the ablation depth is slowly increased in the later stages of laser direct writing to protect the mask substrate 101 from damage.

[0087] In the laser direct writing process, the pulsed laser needs to meet the following requirements: (1) The pulse width can be small enough so that when the pulsed laser ablates the mask material layer 106, the influence of the hydrodynamic process can be ignored. The processing energy of the pulsed laser is more concentrated, so that the energy required to reach the ablation threshold of the mask material layer 106 is lower, thereby greatly reducing the energy loss of laser direct writing; (2) The time of the pulsed laser acting on the mask material layer 106 is extremely short. The heat conduction effect and heat diffusion effect in the laser direct writing process are not obvious, which improves and eliminates the phenomenon of unnecessary damage and destruction of the surrounding materials caused by the heat conduction effect and heat diffusion effect, thereby ensuring the processing accuracy of laser direct writing; (3) The laser pulse width is small enough so that when the pulsed laser ablates the mask material layer 106, the influence of the hydrodynamic process can be ignored. The processing energy of the pulsed laser is more concentrated, so that the energy required to reach the ablation threshold of the mask material layer 106 is lower, thereby greatly reducing the energy loss of laser direct writing; (4) The time of the pulsed laser acting on the mask material layer 106 is extremely short, so that the heat conduction effect and heat diffusion effect in the laser direct writing process are not obvious, thereby improving and eliminating the phenomenon of unnecessary damage and destruction of the surrounding materials caused by the heat conduction effect and heat diffusion effect, thereby ensuring the processing accuracy of laser direct writing; (5) The laser pulse width is small enough so that when the pulsed laser ablates the mask material layer 106, the heat conduction effect and heat diffusion effect in the laser direct writing process can be lower, thereby improving the processing energy required to reach the ablation threshold of the mask material layer 106, and thus greatly reducing the energy loss of laser direct writing. The pulse duration is extremely short, the peak intensity of the pulsed laser is extremely high, and the multilayer stacked film in the mask material layer 106 absorbs the energy of the pulsed laser nonlinearly. When laser direct writing is performed on the mask material layer 106, the diffraction limit can be broken, and the ablation threshold of the bottom or subbottom film in the mask material layer 106 can be reached, thereby penetrating the bottom or subbottom film in the mask material layer 106 for ablation and achieving fine processing; (4) During the laser direct writing process, the removal of each film in the mask material layer 106 by the pulsed laser is mainly carried out by direct vaporization, and the effects of material melting, flow and re-solidification caused by the pulsed laser are minimized, thereby ensuring the pattern accuracy of laser direct writing.

[0088] Optionally, the pulsed laser is a femtosecond laser with a pulse width of only a few quadrillionths of a second and high energy.

[0089] It should be understood that the mask manufacturing method of this embodiment can be implemented using any suitable process equipment system in the art, but it is preferred to use the mask manufacturing system of the present invention.

[0090] Please refer to Figure 4 The mask manufacturing system provided in this embodiment includes a pulsed laser deposition device 200, a pulsed laser direct writing device 204, and a system control device 202 integrated on the same process machine.

[0091] In this regard, please combine Figure 2 The pulsed laser deposition apparatus 200 uses a pulsed laser on the process equipment to perform pulsed laser deposition on a mask substrate 101 to form a desired mask material layer 106 on the mask substrate 101, obtaining a blank mask. The pulsed laser direct writing apparatus 204 further uses the pulsed laser on the process equipment to perform laser direct writing on the mask material layer 106, forming a desired pattern 107 in the mask material layer 106, obtaining a mask. The system control unit 202 is coupled to the pulsed laser deposition apparatus 200 and the pulsed laser direct writing apparatus 204, and is used to control the coordinated operation of the pulsed laser deposition apparatus 200 and the pulsed laser direct writing apparatus 204.

[0092] It is worth noting that any one of the system control unit 202, the pulsed laser deposition device 200, and the pulsed laser direct writing device 204 can be divided into multiple modules, or at least part of the functions of one or more of these devices can be combined with at least part of the functions of other devices and implemented in a single module. Furthermore, at least one of the system control unit 202, the pulsed laser deposition device 200, and the pulsed laser direct writing device 204 can be at least partially implemented as hardware circuitry, such as a field-programmable gate array (FPGA), a programmable logic array (PLA), a system-on-a-chip, a system-on-a-substrate, a system-on-package, an application-specific integrated circuit (ASIC), or any other reasonable method of integrating or packaging circuitry, or as hardware or firmware implementation, or as a suitable combination of software, hardware, and firmware implementations. Alternatively, at least one of the system control unit 202, the pulsed laser deposition device 200, and the pulsed laser direct writing device 204 can be at least partially implemented as a computer program module, which, when run by a computer, can execute the functions of the corresponding module.

[0093] As an example, please refer to Figure 5The pulsed laser deposition apparatus 200 includes a first focusing mechanism 17, a deposition chamber 19 with a light-transmitting window 18, and a stage 14 and a target 15 disposed in the deposition chamber 19. The pulsed laser direct writing apparatus 204 includes a laser direct writing chamber 29 and a reflector 20, a second beam expander 21, a first dichroic prism 23, a second dichroic prism 24, and a second scanning focusing mechanism 25 disposed sequentially along the optical path in the laser direct writing chamber 29.

[0094] In addition to the system control unit 202, the pulsed laser deposition unit 200, and the pulsed laser direct writing unit 204, the manufacturing system of this example also includes a laser 1, a shutter 2, a quarter-wave plate 3, a polarizer 4, and a second beam splitter 16, which are integrated on the process machine and arranged sequentially along the optical path. It also includes a second transition chamber 50 and a robotic transport device 50a integrated on the process machine.

[0095] Alternatively, the pulsed laser direct writing device 204 may further include an illumination source 22, a second focusing mechanism 26, and a detector 27 disposed in the laser direct writing chamber 29.

[0096] It should be understood that in some examples, the pulsed laser deposition apparatus 200 and the pulsed laser direct writing apparatus 204 can operate sequentially, allowing pulsed laser deposition to be performed on the same sample 10 first, followed by laser direct writing. In this case, corresponding electronic control components such as shutters can be installed in the pulsed laser deposition apparatus 200 and the pulsed laser direct writing apparatus 204 to control the opening and closing of the pulsed laser in their respective chambers. In other examples, the pulsed laser deposition apparatus 200 and the pulsed laser direct writing apparatus 204 can also operate simultaneously, allowing the pulsed laser deposition apparatus 200 to perform pulsed laser deposition on one sample 10, while the pulsed laser direct writing apparatus 204 performs laser direct writing on another sample 10 (which has already undergone pulsed laser deposition).

[0097] Laser 1 is used to generate pulsed laser light. Laser 1 can be any suitable laser, such as a ruby ​​laser, CO2 laser, ultraviolet laser, Nd glass laser, or excimer laser. The pulse width (PWM) of the generated pulsed laser light can be any suitable level, such as femtosecond, picosecond, microsecond, or nanosecond. Laser 1 can be an electronically controlled component, coupled to the system's main control unit 202. Therefore, laser 1 can control and adjust the wavelength, pulse width, and power of the generated pulsed laser light according to the control or adjustment commands from the system's main control unit 202.

[0098] The pulsed laser generated by laser 1 passes sequentially through shutter 2, quarter-wave plate 3, polarizer 4, and second beam splitter 16. Shutter 2 can be switched on and off by the system's main control unit 202 via high and low level signals, thus controlling the pulsed laser's activation and deactivation. The second beam splitter 16 splits the received laser into two paths: one path passes through the first focusing mechanism 17 and the light-transmitting window 18 to illuminate the target 15 in the deposition chamber 19; the other path passes through the reflector 20, the second beam expander 21, the first dichroic prism 23, the second dichroic prism 24, and the second scanning focusing mechanism 25 to illuminate the sample 10 held on the stage 28 in the laser direct-writing chamber 29 of the laser direct-writing device 204.

[0099] The illumination light generated by the illumination source 22 is irradiated onto the sample 10 supported by the support stage 28 through the first dichroic prism 23, the second dichroic prism 24, and the second scanning focusing mechanism 25. The illumination light reflected from the surface of the sample 10 supported by the support stage 28 is converged into the detector 27 through the second scanning focusing mechanism 25, the second dichroic prism 24, and the second focusing mechanism 26. Thus, the detector 27 can acquire the image effect of laser direct writing in real time and feed the corresponding data back to the system control device 202. This allows the system control device 202 to adjust and optimize the process parameters and scanning path of the laser direct writing device 204 to ensure the final effect of laser direct writing.

[0100] The second beam expander 21 is mainly used to expand the beam diameter of the pulsed laser reflected by the reflector 20 and reduce the emission angle of the pulsed laser beam.

[0101] Compared to omitting the second beam expander 21, with the second beam expander 21, the pulsed laser beam reflected by the reflector 20 can make the energy of the light beam focused onto the sample 10 by the second scanning focusing mechanism 25 more uniformly distributed within the light beam range.

[0102] In this embodiment, the product of the beam diameter and divergence angle of the pulsed laser output by laser 1 is an optical invariant, approximately a constant value. When the second beam expander 21 expands the beam diameter of the pulsed laser reflected by mirror 26 by a factor of x, its divergence angle is correspondingly compressed to 1 / x of the original. In summary, by setting the second beam expander 21 in this optical path, the requirements for other optical components in this optical path can be reduced, and the energy of the light beam focused on sample 10 can be more uniformly distributed within the light beam range, thereby improving the energy utilization effect of the pulsed laser. Optionally, the second beam expander 21 can be an electronically controlled component, which can adjust and control its beam expansion ratio according to the control commands or adjustment commands of the system's main control device 202.

[0103] Optionally, the second beam expanding mechanism 21 may be a laser beam expanding collimator.

[0104] The second scanning and focusing mechanism 25 is used to control laser parameters such as the focal length and focal plane of the pulsed laser and to achieve scanning parameters such as the scanning path. The second scanning and focusing mechanism 25 may include a field lens, also known as a flat field focusing lens or F-theta lens. Unlike ordinary spherical mirrors that can only focus on curved surfaces, this field lens is specially designed so that the incident laser beam, after being focused and emitted, can be focused on the surface of the sample 10 in the laser direct-writing chamber 29. The incident angle of the incident laser is linearly related to the position of the emitted laser, and it can precisely control the focusing position of the pulsed laser on the surface of the sample 10 in the laser direct-writing chamber 29. The second scanning and focusing mechanism 25 may also include a galvanometer, which consists of two mirrors respectively connected to a swing motor. A specific path is set on the computer and the motion signal is sent to the system control unit 202. The system control unit 202 controls the rotation of the reflector by controlling the motor, so that the pulsed laser oscillates on the surface of the sample 10 in the laser direct writing chamber 29 along a specific path. This, combined with the movement of the support stage 28 in the laser direct writing chamber 29 used to support the sample 10, scans the surface of the sample 10 in the laser direct writing chamber 29, thereby realizing ultrafast serial laser direct writing.

[0105] Optionally, the second scanning focusing mechanism 25 may include an electronic control component, which can adjust the focusing parameters such as focal length and focal plane of the pulsed laser incident on the surface of the sample 10 in the laser direct writing chamber 29, as well as the scanning parameters such as scanning step length, scanning speed, and scanning path, according to the control or adjustment commands of the system's main control device 202.

[0106] The first focusing mechanism 17 is used to focus a single pulsed laser emitted from the second beam splitter 16 onto the target material 15, and the stage 14 is used to hold the sample 10 used to manufacture a blank mask.

[0107] A transition chamber 50 is positioned between the deposition chamber 19 and the laser direct writing chamber 29 to allow the sample 10 to queue before the deposition chamber 19 and the laser direct writing chamber 29. A robotic arm transfer device 50a is used to transfer the sample between the deposition chamber 19, the transition chamber 50, and the laser direct writing chamber 29.

[0108] Furthermore, it should be understood that, Figure 5 The specific structure shown is merely an example and does not imply that the manufacturing system of this embodiment only has the structure shown in the figure; it may further include any suitable optical or electronic components as required. For example, please refer to... Figure 5 A reflector is placed between the second beam splitter 16 and the first focusing mechanism 17, so that one pulse laser emitted from the second beam splitter 16 is delivered to the first focusing mechanism 17 at the optimal angle.

[0109] In summary, the mask manufacturing method and system of this embodiment can automatically manufacture blank masks using pulsed lasers generated by the same laser on the same process machine and perform laser direct writing on the blank masks to form masks with the required patterns. The process is simple, the manufacturing cost is low, the production efficiency is high, the mask performance is stable, the yield is high, the process machine equipment cost is low, and the integration is high.

[0110] Second Embodiment

[0111] Please refer to Figure 6 This embodiment provides a method for manufacturing a photomask, which also includes the following steps:

[0112] S1, pulsed laser deposition is performed on a mask substrate using a pulsed laser on a process machine to form the required mask material layer on the mask substrate, thereby obtaining a blank mask.

[0113] S2, the pulsed laser is further used on the process machine to perform laser direct writing on the mask material layer to form the desired pattern in the mask material layer, thereby obtaining a mask.

[0114] The difference between this embodiment and the manufacturing method of the first embodiment is that step S1 includes cyclically executing the following sub-steps:

[0115] S11, The pulsed laser is used on the process machine to perform pulsed laser deposition on the mask substrate to obtain a blank mask with a corresponding mask material layer;

[0116] S12, Detect whether the performance of the blank mask meets the target;

[0117] S13, when the performance of the blank mask is found to be substandard, a corresponding laser surface treatment method is selected according to the detection result, and the blank mask is subjected to laser surface treatment on the process machine to repair the surface of the mask material layer, or to remove the mask material layer and repair the surface of the mask substrate.

[0118] After sub-step S11, which involves depositing the mask material layer 106, sub-step S12 is performed. In sub-step S12, the deposited mask material layer 106 or the blank mask formed by the mask material layer 106 and the mask substrate 101 can be inspected using any desired detection method to determine whether the performance meets the target. For example, the surface morphology of the blank mask can be inspected online in real time using a scanning probe microscope (SPM). The inspection results can include information such as the current surface roughness or surface flatness, as well as information such as the height and film thickness at various locations. Optical performance indicators such as transmittance and reflectance of the blank mask can also be detected using appropriate optical inspection devices. The inspection results are then compared with the corresponding target values ​​or target ranges to determine whether the current performance of the blank mask meets the target.

[0119] If it is determined that the current performance of the blank mask does not meet the target, the blank mask is sent to sub-step S13 for laser surface treatment to trim the surface of the mask material layer, or to remove the mask material layer and trim the surface of the mask substrate. In this step, a suitable laser surface treatment method can be selected to perform laser surface treatment on the blank mask based on the detection results of sub-step S12. The optional laser surface treatment methods include one of the following three methods:

[0120] The first method involves using a first laser to perform laser film removal in order to remove a film layer of a corresponding thickness from the mask substrate;

[0121] The second method involves using a second laser, different from the first laser, to perform laser polishing on the surface of the film layer on the mask substrate.

[0122] The third method involves first using the first laser for laser film removal, and then using the second laser for laser polishing.

[0123] The first or second laser mentioned above is a pulsed laser generated by the laser used in pulsed laser deposition. That is, the laser removal or laser polishing process uses the same pulsed laser generated by the same laser as the pulsed laser deposition process.

[0124] In practical applications, if sub-step S12 detects that the main performance issue of the blank mask is excessive surface roughness, while other performance aspects are very close to the target, then in sub-step S13, a second laser can be used to laser polish the surface of the blank mask to achieve the target surface roughness of the mask material layer 106. If sub-step S12 detects that all aspects of the current performance of the blank mask differ significantly from the target, then in sub-step S13, a first laser can be used to laser-remove the surface of the blank mask, removing all mask material layers 106 on the mask substrate 101. Then, a second laser can be used to laser-polish the surface of the mask substrate to make it clean, flat, and to the required degree, laying the foundation for executing sub-step S11 again. If, in sub-step S12, the analysis of the previous and current test results reveals that the mask material layer deposited in sub-step S11 results in the blank mask not meeting the target performance, then in sub-step S13, a first laser can be selected to perform laser removal on the surface of the blank mask to remove the mask material layer 106 deposited on the mask substrate 101 in sub-step S11, laying the foundation for executing sub-step S11 again.

[0125] Furthermore, in order to improve the efficiency and effect of laser surface treatment in sub-step S13, the surface morphology of the blank mask can be detected online in real time during the laser surface treatment process, and the process parameters of laser surface treatment in sub-step S13 can be adjusted online in real time based on the detection results of the surface morphology. For example, the wavelength, power, focusing parameters (including focal plane size, the angle between the focal plane and the mask substrate surface, etc.) of the first laser or the second laser, as well as the scanning parameters (such as scanning path, scanning step size, scanning speed, etc.) can be adjusted.

[0126] The following example, which involves laser removal followed by laser polishing in sub-step S13, will be used to illustrate the specific process of sub-step S13 in detail.

[0127] First, please combine Figure 6 and Figure 2A pulsed laser with a pulse width of any suitable level, such as femtosecond, picosecond, microsecond, or nanosecond, can be used as the first laser. This first laser is focused and irradiates the mask material layer 106 in a scanning manner. Due to the material properties of the mask material layer 106 and its difference from the material properties of the mask substrate 101, when the first laser is focused on the surface of the mask material layer 106, a large amount of heat accumulates in the near-surface region in a very short time, causing the surface temperature of the mask material layer 106 to rise rapidly. When the temperature reaches the melting point of the near-surface layer material (i.e., the surface material) of the mask material layer 106, the near-surface layer material begins to melt. When the temperature further reaches the boiling point of the surface layer material, the near-surface layer material begins to evaporate, while the temperature of the mask substrate 101 remains essentially at room temperature. Thus, the mask material layer 106 can be quickly removed from the mask substrate 101, thereby obtaining the mask substrate 101, and the surface of the mask substrate 101 suffers minimal damage during the laser removal process. The removal rate of the mask material layer 106 depends on parameters such as the properties and thickness of the mask material layer and the laser power used.

[0128] Optionally, during the removal of the mask material layer 106 by the first laser, the surface morphology of the blank mask (i.e., the remaining mask material layer and the exposed mask substrate) can be detected online in real time using a scanning probe microscope (SPM) or similar device. The detection results of the surface morphology can include information such as the current surface roughness or surface flatness, as well as information such as the position, height, and thickness of the remaining mask material layer. Based on the detection results of the surface morphology, the laser removal process parameters are adjusted, including adjusting the wavelength, power, and focusing parameters (including focal plane size, the angle between the focal plane and the mask substrate surface, etc.) of the first laser irradiating the surface of the mask material layer 106, and adjusting the scanning parameters (including scanning path, scanning speed, scanning step size, etc.) of the laser scanning of the blank mask surface based on the first laser. The remaining mask material layer 106 is then removed based on the online adjusted laser removal process parameters. Therefore, the laser removal process parameters are adjusted while removing the film until the removal effect of the mask material layer 106 on the mask substrate 101 reaches the target. This ensures the removal effect on the mask substrate 101, avoids unnecessary damage to the mask substrate 101, improves the efficiency of laser removal, and also reduces the workload of subsequent laser polishing steps, thereby improving the efficiency of subsequent laser polishing.

[0129] It should be understood that, in this embodiment, when the mask material layer 106 is composed of multiple layers of films with different properties, the parameters of the first laser can be set according to the distance between the film and the surface of the mask substrate 101 and the material properties of the film. At least one parameter of the first laser is different when removing different films. For example, as the removal depth increases, the power of the first laser decreases and the scanning step size decreases. This allows for large-scale removal in the early stage of removal and fine removal in the later stage, thereby improving removal efficiency and protecting the mask substrate 101 from damage.

[0130] After laser removal is completed in sub-step S13, a second laser can be generated using any suitable laser, such as a carbon dioxide laser. This second laser scans and focuses onto the mask substrate 101, thereby performing laser polishing on the surface of the mask substrate 101. When the second laser is focused onto a corresponding position on the mask substrate 101, it can break the chemical bonds in the surface material of the mask substrate 101 at that position, or destroy the lattice structure in the surface material of the mask substrate 101 at that position, thus removing the surface material of the mask substrate 101 at that position. In other words, this laser polishing is actually a cold polishing of the surface of the mask substrate 101. Compared with the hot polishing achieved by using the thermal effect of the laser (that is, using the thermal effect of the laser to melt, flow or evaporate the surface material on the substrate to achieve a flat surface of the substrate, the temperature gradient is large during the hot polishing process, resulting in large thermal stress on the substrate surface and easy to produce cracks and other problems), the thermal stress brought to the surface of the mask substrate 101 is very small and can be ignored. Therefore, it will not cause defects such as cracks, scratches, micro-defects, or residual "ghost images" on the surface of the mask substrate, nor will it affect the surrounding materials. Moreover, it is easy to control the amount of material removed (e.g., the thickness removed), so that the surface roughness of the mask substrate 101 can meet the requirements for directly manufacturing new blank masks.

[0131] Optionally, when laser polishing the mask substrate 101 with the second laser, the surface morphology of the mask substrate 101 can be detected online in real time using a scanning probe microscope (SPM) or similar device. The detection results of the surface morphology can include information such as the current surface roughness or surface flatness, as well as information such as the height of various positions on the mask substrate 101. Based on the detection results of the surface morphology, the laser polishing process parameters can be adjusted. For example, the wavelength, power, and focusing parameters (including focal plane size and the angle between the focal plane and the mask substrate surface) of the second laser irradiating the surface of the mask substrate 101 can be adjusted, as well as the scanning parameters based on the second laser (including scanning speed and scanning step size). Based on the online adjusted laser polishing process parameters, the surface of the mask substrate 101 can be further polished to eliminate protrusions and depressions on the surface of the mask substrate 101. Therefore, the laser polishing process parameters are adjusted while polishing until the surface roughness of the mask substrate 101 meets the requirements. This ensures the polishing effect of the mask substrate 101, avoids unnecessary damage to the mask substrate 101, and improves the efficiency of laser polishing.

[0132] After sub-step S13, the process can return to sub-step S11 to deposit a new mask material layer on the mask substrate again. This process is repeated from sub-steps S11 to S13 until the obtained blank mask meets the target. Optionally, if the performance of the blank mask does not meet the target, the parameters of the pulsed laser deposition process are adjusted based on the detection result. This allows the pulsed laser deposition process to be performed on the laser-treated blank mask in step S11 based on the adjusted parameters after the laser surface treatment in step S13. This improves the effectiveness of re-performing the pulsed laser deposition process, minimizes the number of cycles from S11 to S13, and increases the efficiency of manufacturing a qualified blank mask.

[0133] Furthermore, after the performance of the blank mask reaches the target, step S2 can be further performed, namely, laser direct writing of the mask material layer 106 of the blank mask.

[0134] In this embodiment, the first and second lasers used in laser surface treatment can both originate from the same laser source that generates the pulsed laser required for the pulsed laser deposition process. In other embodiments, one of the first and second lasers used in laser surface treatment originates from the same laser source as the pulsed laser used in the pulsed laser deposition process, while the other laser can originate from a different laser source. This other laser can be a pulsed laser with a pulse width at any suitable level, such as microseconds, nanoseconds, femtoseconds, or picoseconds. It can also be a continuous wave (CW) laser or a quasi-continuous wave (QCW) laser.

[0135] It should be understood that the mask manufacturing method of this embodiment can be implemented using any suitable equipment or machine system in the art, but preferably using the empty mask manufacturing system of this embodiment.

[0136] Please refer to Figure 7 The mask manufacturing system provided in this embodiment includes a pulsed laser deposition device 200, a laser surface treatment device 201, a detection device 203, a system control device 202, and a pulsed laser direct writing device 204, all integrated on the same process machine.

[0137] The difference between the mask manufacturing system in this embodiment and the mask manufacturing system in the first embodiment is that a laser surface treatment device 201 and a detection device 203 are added.

[0138] The detection device 203 is used to detect whether the performance of the blank mask provided by the pulsed laser deposition apparatus 200 meets the target. For example, the detection device 203 can detect whether at least one of the following performance indicators—thickness of the mask material layer 106 or the mask substrate 101, surface flatness, and transmittance and reflectance of the blank mask—meets the target.

[0139] The laser surface treatment apparatus 201 is used to select an appropriate laser surface treatment method based on the detection result when the detection device 203 detects that the performance of the blank mask does not meet the standard. This laser surface treatment is applied to the surface of the film layer on the mask substrate 101 to repair the surface of the mask material layer 106 of the blank mask, or to remove the mask material layer 106 from the mask substrate 101 and repair its surface. When the mask substrate 101 is not covered by a mask material layer 106, the laser surface treatment is applied to the surface layer of the mask substrate 101. When the mask substrate 101 is covered by a mask material layer 106, the laser surface treatment is applied to a portion or all of the thickness of the mask material layer 106 on the mask substrate 101. Optionally, the laser surface treatment apparatus 201 can provide one of the following three laser surface treatment methods:

[0140] The first method involves using a first laser to perform laser film removal in order to remove a film layer of a corresponding thickness from the mask substrate;

[0141] The second method involves using a second laser, different from the first laser, to perform laser polishing on the surface of the film layer on the mask substrate.

[0142] The third method involves first using the first laser for laser film removal, and then using the second laser for laser polishing.

[0143] The system's main control unit 202 is used to control the coordinated operation of the laser surface treatment unit 201, the pulsed laser deposition unit 200, the pulsed laser direct writing unit 204, and the detection unit 203. When the detection unit 203 detects that the performance of the blank mask output by the pulsed laser deposition unit 200 is not up to standard, it further controls the mask substrate 101 (i.e., sample 10) to be cyclically transferred and processed in the pulsed laser deposition unit 200, the detection unit 203, and the laser surface treatment unit 201 until the performance of the blank mask reaches the target.

[0144] Optionally, the system control unit 202 is further configured to adjust the process parameters of the pulsed laser deposition apparatus 200 when the detection device 203 detects that the performance of the blank mask does not meet the standard, so that the pulsed laser deposition apparatus 200 executes the subsequent pulsed laser deposition process based on the adjusted process parameters.

[0145] It is worth noting that the pulsed laser required for the laser surface treatment device 201 to perform the laser film removal process or the laser polishing process comes from the same laser as the pulsed laser used by the pulsed laser deposition device 200 to perform the pulsed laser deposition process.

[0146] Furthermore, any one of the system control unit 202, laser surface treatment unit 201, pulsed laser deposition unit 200, detection unit 203, and pulsed laser direct writing unit 204 can be divided into multiple modules, or at least part of the functions of one or more of these units can be combined with at least part of the functions of other units and implemented in a single module. Additionally, at least one of the system control unit 202, laser surface treatment unit 201, pulsed laser deposition unit 200, detection unit 203, and pulsed laser direct writing unit 204 can be at least partially implemented as hardware circuitry, such as a field-programmable gate array (FPGA), a programmable logic array (PLA), a system-on-a-chip, a system-on-a-substrate, a system-on-package, an application-specific integrated circuit (ASIC), or any other reasonable method of integrating or packaging circuitry, or a suitable combination of software, hardware, and firmware implementations. Alternatively, at least one of the system control unit 202, laser surface treatment unit 201, pulsed laser deposition unit 200, detection unit 203, and pulsed laser direct writing unit 204 can be at least partially implemented as a computer program module, which can perform the functions of the corresponding module when the program is run by a computer.

[0147] As an example, please refer to Figure 8The pulsed laser deposition apparatus 200 and pulsed laser direct writing apparatus 204 of this embodiment have the same structure as those of the first embodiment. Specifically, the pulsed laser deposition apparatus 200 includes a first focusing mechanism 17, a deposition chamber 19 with a light-transmitting window 18, and a stage 14 and a target material 15 disposed in the deposition chamber 19. The pulsed laser direct writing apparatus 204 includes a laser direct writing chamber 29 and a reflector 20, a second beam expander 21, a first dichroic prism 23, a second dichroic prism 24, and a second scanning focusing mechanism 25 disposed sequentially along the optical path in the laser direct writing chamber 29. The pulsed laser direct writing apparatus 204 also includes an illumination source 22, a second focusing mechanism 26, and a detector 27 disposed in the laser direct writing chamber 29.

[0148] The laser surface treatment apparatus 201 of this embodiment includes a first beam expander 6, a focusing mechanism 7a, a first scanning focusing mechanism 7b, and a laser surface treatment chamber 11 with a light-transmitting window 9. In addition to the system control unit 202, pulsed laser deposition apparatus 200, detection device 203, laser surface treatment apparatus 201, and pulsed laser direct writing apparatus 204, the manufacturing system of this example also includes a laser 1, a shutter 2, a quarter-wave plate 3, a polarizer 4, a first beam splitter 5, and a second beam splitter 16, all integrated on the process platform and arranged sequentially along the optical path. It also includes a first transition chamber 12, a second transition chamber 50, and robotic arm transfer devices 12a and 50a integrated on the process platform.

[0149] The first beam splitter 5 splits the pulsed laser emitted from the polarizer 4 (i.e., from the laser 1) into two paths. One path passes through the first beam expander 6, the focusing mechanism 7a, the first scanning focusing mechanism 7b, and the light transmission window 9 to irradiate the sample 10 in the laser surface treatment chamber 11. The other path passes through the second beam splitter 16 to split into two paths again. One path passes through the first focusing mechanism 17 and the light transmission window 18 to irradiate the target 15 in the deposition chamber 19. The other path passes through the reflector 20, the second beam expander 21, the first dichroic prism 23, the second dichroic prism 24, and the second scanning focusing mechanism 25 to irradiate the sample 10 carried on the stage 28 in the chamber 29 of the laser direct writing device 204.

[0150] The first beam expander 6 is mainly used to expand the beam diameter of the pulsed laser emitted from the first beam splitter 5 and reduce the beam emission angle of the emitted pulsed laser. Compared with the case where the first beam expander 6 is omitted, with the first beam expander 6, the light energy of the pulsed laser beam emitted from the first beam splitter 5 after being expanded by the first beam expander 6 and irradiating the sample 10 is more uniformly distributed within the light beam area.

[0151] In this embodiment, the product of the beam diameter and divergence angle of the pulsed laser output by laser 1 is an optical invariant, approximately a constant value. When the first beam expander 6 expands the beam diameter of the pulsed laser emitted by the first beam splitter 5 by a factor of x, the divergence angle of the pulsed laser emitted by the first beam expander 6 is correspondingly compressed to 1 / x of the original value. In summary, by setting the first beam expander 6 in this optical path, the requirements for other optical components in this optical path can be reduced, and the energy distribution of the light focused on the sample 10 can be made more uniform, thereby improving the energy utilization effect of the pulsed laser.

[0152] Optionally, the first beam expander 6 may be an electronically controlled component, which can adjust and control the beam expansion ratio of the first beam expander 6 according to the control command or adjustment command of the system general control device 202.

[0153] Optionally, the first beam expanding mechanism 6 may be a laser beam expanding collimator.

[0154] The focusing mechanism 7a and the first scanning focusing mechanism 7b can form a laser control mechanism 8 for controlling laser parameters such as focal length and focal plane, and realizing scanning parameters such as scanning path. The focusing mechanism 7a is used to adjust the focal length of the laser incident on the surface of the sample 10 in the laser surface treatment chamber 11 and the angle between the focal plane of the laser and the surface of the sample 10 in the laser surface treatment chamber 11. The focusing mechanism 7a may include a field lens, also known as a flat field focusing lens or F-theta lens. Unlike ordinary spherical lenses that can only focus on curved surfaces, this field lens is specially designed so that after the incident laser beam is focused and emitted, it can be focused on the surface of the sample 10 in the laser surface treatment chamber 11. The incident angle of the incident laser is linearly related to the position of the emitted laser. When used in conjunction with the first scanning focusing mechanism 7b, the focusing position of the laser on the surface of the sample 10 in the laser surface treatment chamber 11 can be precisely controlled. The focusing mechanism 7a may include an electronic control component, which can adjust the focusing parameters such as the focal length and focal plane of the laser incident on the surface of the sample 10 in the laser surface treatment chamber 11 according to the control command or adjustment command of the system general control device 202.

[0155] The first scanning and focusing mechanism 7b is used to perform laser scanning on the sample 10 in the laser surface treatment chamber 11 using the laser emitted from the focusing mechanism 7a. Scanning parameters such as scanning speed and scanning step size are set and adjusted according to instructions from the system control unit 202. Optionally, the first scanning and focusing mechanism 7b includes a galvanometer, which consists of two mirrors respectively connected to oscillating motors. A specific path is set on the computer and motion signals are sent to the system control unit 202. The system control unit 202 controls the rotation of the mirrors by controlling the motors, causing the laser to oscillate along a specific path on the surface of the sample 10 in the laser surface treatment chamber 11. This, combined with the movement of the support stage (not shown) in the laser surface treatment chamber 11 used to support the sample 10, scans the surface of the sample 10 in the laser surface treatment chamber 11, achieving serial processing with ultrafast lasers, rapidly removing the mask material layer on the sample 10 in the laser surface treatment chamber 11, or polishing the mask substrate after mask removal.

[0156] A transition chamber 12 is disposed between the laser surface treatment chamber 11 and the deposition chamber 19 to allow the sample 10 to queue in front of the laser surface treatment chamber 11 and in front of the deposition chamber 19. A robotic arm transfer device 12a is used to transfer the mask substrate (i.e., the sample 10) between the laser surface treatment chamber 11, the transition chamber 12, and the deposition chamber 19.

[0157] Figure 8 The example shown enables the laser surface treatment apparatus 201 to perform laser surface treatment functions such as laser film removal or laser polishing, and to perform pulsed laser deposition using the same pulsed laser. The laser surface treatment apparatus 201 and the pulsed laser deposition apparatus 200 are integrated on the same process platform, and optical components such as the laser 1, shutter 2, quarter-wave plate 3, polarizer 4, and first beam splitter 5 are reused, simplifying the platform structure, reducing platform size, and lowering equipment costs. Furthermore, during the manufacturing of the blank mask, the sample 10 can be moved back and forth between the laser surface treatment chamber 11 and the deposition chamber 19 based on the detection results of the detection device 203, ensuring product yield.

[0158] As another example, please refer to Figure 9 The manufacturing system in this example is similar to Figure 8 The difference in the manufacturing system shown is that it further includes a surface morphology detection unit 30, which is installed inside the laser surface treatment chamber 11. It can be regarded as part of the laser surface treatment device 201, or as a corresponding part of the detection device 203 integrated with the laser surface treatment device 201.

[0159] Specifically, the surface topography detection unit 30 may include a scanning probe microscope (SPM). Scanning probe microscope (SPM) is a general term for a class of instruments, primarily scanning tunneling microscopes (STM) and scanning force microscopes (SFM), represented by atomic force microscopes (AFM). Please refer to [reference needed]. Figure 9 As shown, the two key components of the SPM are the probe 35 and the scanner. The scanner includes a scanning light source 33 and a scanning drive arm 34. The probe 35 is mounted at the front end of the scanning drive arm 34. The distance between the probe 35 and the sample 10 in the laser surface treatment chamber 11 is controlled by the movement of the scanner. When the probe 35 and the sample 10 in the laser surface treatment chamber 11 get close to a certain extent, if there is a sufficiently sensitive physical quantity P = P(z) that changes monotonically with the distance between the probe 35 and the sample 10 in the laser surface treatment chamber 11 (e.g., van der Waals force), then this physical quantity can be detected by the feedback system (FS) composed of the signal receiver 32 and the signal processor 31. This allows the information on the surface position and corresponding height of the sample 10 in the laser surface treatment chamber 11 to be obtained (i.e., the surface roughness information of the sample 10 in the laser surface treatment chamber 11), thereby depicting the surface morphology of the sample 10 in the laser surface treatment chamber 11. The signal processor 31 also feeds back the surface morphology detection results it obtains to the system control unit 202, so that the system control unit 202 can issue corresponding instructions to the laser 1, the first beam expander 6, the focusing mechanism 7a and the first scanning focusing mechanism 7b, etc., to adjust the process parameters of laser surface treatment.

[0160] Figure 9 The example shown is in the implementation Figure 8 Based on the functionality of the example shown, the system further implements the function of adjusting the process parameters of laser surface treatment in real time online based on the online detection results of the surface morphology detection unit 30.

[0161] As another example, please refer to Figure 10 The manufacturing system in this example is similar to Figure 9 The manufacturing system shown is different in that it further includes a laser 41, a reflection system, and a beam combining mechanism 40.

[0162] In this process, lasers 1 and 41 produce different lasers. When the laser generated by laser 41 is used as the first laser for laser film removal, the laser generated by laser 1 is used as the second laser for laser polishing. Alternatively, one of the first and second lasers can also be used for pulsed laser deposition and pulsed laser direct writing; in this case, the laser is a pulsed laser with a pulse width at any suitable level, such as microseconds, nanoseconds, femtoseconds, or picoseconds. The other laser, which is different from the pulsed laser used in the pulsed laser deposition process, can be a pulsed laser with a pulse width at any suitable level, such as microseconds, nanoseconds, femtoseconds, or picoseconds; it can also be a continuous wave (CW) laser or a quasi-continuous wave (QCW) laser.

[0163] Optionally, laser 1 is a femtosecond pulsed laser and the pulsed laser generated is used as a second laser for laser polishing, and the laser generated by laser 1 is also used for pulsed laser deposition.

[0164] The reflection system can be appropriately configured or omitted based on the laser angle emitted from the laser 41 and the laser incident angle allowed by the beam combining mechanism 40. In this example, the reflection system includes mirrors 42 and 43, which are used to reflect the laser emitted from the laser 41 into the beam combining mechanism 40.

[0165] The beam combining mechanism 40 receives pulsed laser light generated by the first beam splitter 5 and the laser light generated by the laser 41 in a time-division manner, and directs the received pulsed laser light (i.e., the first laser or the second laser) into the first beam expanding mechanism 6 at the same angle. Optionally, the beam combining mechanism 40 may have an electronic control component that can control and adjust the laser emission angle according to the control or adjustment commands of the system master control device 202.

[0166] Figure 10 The example shown is in the implementation Figure 9 Building upon the functionality of the example shown, it further achieves compatibility between two laser surface treatment methods: laser decoction and laser polishing.

[0167] Furthermore, it should be understood that, Figures 8 to 10 The specific structure shown is merely an example and does not imply that the manufacturing system of this embodiment only has the structure shown in the figure; it may further include any suitable optical or electronic components as required. For example, please refer to... Figure 8 A reflector is disposed between the first beam expanding mechanism 6 and the focusing mechanism 7a, thereby delivering the laser emitted from the first beam expanding mechanism 6 to the focusing mechanism 7a at an optimal angle. For example, for... Figure 8The focusing mechanism 7a and the first scanning focusing mechanism 7b can be configured such that the focusing mechanism 7a is at the rear and the first scanning focusing mechanism 7b is at the front. And for... Figure 10 The first beam expanding mechanism 6 and the beam combining mechanism 40 can also be configured such that the first beam expanding mechanism 6 is in front and the beam combining mechanism 40 is behind.

[0168] In summary, the mask manufacturing method and system of this embodiment can perform online performance testing on blank masks after pulsed laser deposition. If the performance of the blank mask does not meet the standards, laser surface treatment can be performed on the blank mask in a timely manner, or even pulsed laser deposition can be performed again. Through the cyclic execution of these steps of pulsed laser deposition (PLD), testing, and laser surface treatment (laser film removal or laser film removal followed by laser polishing), the performance of the final blank mask can be guaranteed to meet the target. Then, laser direct writing can be performed on the blank mask with the target performance to obtain a mask with a pattern, thereby improving the manufacturing yield of the mask (i.e., reducing the scrap rate of the mask) and thus relatively reducing the manufacturing cost of the mask.

[0169] Furthermore, when the performance of the blank mask is found to be substandard, the parameters of the pulsed laser deposition process are adjusted so that subsequent pulsed laser deposition can be performed based on the adjusted parameters. The pulsed laser deposition process has a high target utilization rate and can improve the manufacturing efficiency of the mask.

[0170] Third Embodiment

[0171] As described in the background section, with the increasing integration and shrinking feature sizes of semiconductor devices, the number of photomasks required for semiconductor device fabrication is also increasing. Furthermore, as process node sizes shrink, the manufacturing cost of the photomasks themselves, as well as the cost of discarding defective photomasks, continues to rise, resulting in persistently high production costs for semiconductor devices. Simultaneously, the number of unusable discarded photomasks is increasing exponentially. The handling and management of discarded photomasks incurs significant costs, and the low utilization rate of high-priced photomasks not only wastes resources but also imposes a substantial burden on enterprises.

[0172] Based on this, please refer to Figure 11 This embodiment provides a method for manufacturing a photomask, which can recycle and reuse discarded photomasks, thereby reducing the manufacturing cost of new photomasks. The manufacturing method includes the following steps:

[0173] S0, a mask to be discarded is provided, and the mask to be discarded is subjected to laser surface treatment on the process machine to remove the film layer on the mask substrate of the mask to be discarded, so as to obtain the mask substrate;

[0174] S1, pulsed laser deposition is performed on the mask substrate using a pulsed laser on the process machine to form the required mask material layer on the mask substrate, thereby obtaining a blank mask.

[0175] S2, the pulsed laser is further used on the process machine to perform laser direct writing on the mask material layer to form the desired pattern in the mask material layer, thereby obtaining a mask.

[0176] Step S1 may further include the following sub-steps executed cyclically:

[0177] S11, The pulsed laser is used on the process machine to perform pulsed laser deposition on the mask substrate to obtain a blank mask with a corresponding mask material layer;

[0178] S12, Detect whether the performance of the blank mask meets the target;

[0179] S13, when the performance of the blank mask is found to be substandard, a corresponding laser surface treatment method is selected according to the detection result, and the blank mask is subjected to laser surface treatment on the process machine to repair the surface of the mask material layer, or to remove the mask material layer and repair the surface of the mask substrate.

[0180] Steps S1 and S2 described above are the same as in the second embodiment, and will not be repeated here.

[0181] The photomask to be discarded provided in step S0 can be any photomask that needs to be discarded. The reasons for discarding these photomasks can be as follows: (1) The photomask's performance deteriorates after being used multiple times (e.g., the feature size CD value decreases), making it unusable and requiring discarding; (2) When patterning a blank photomask to manufacture a patterned photomask, the patterned photomask produced is unqualified for various reasons and needs to be discarded; (3) The blank photomask itself needs to be discarded because of surface defects; (4) During the manufacturing or repair of the photomask, it is discovered that there are difficult-to-repair pattern defects on the manufactured photomask, and it needs to be discarded as a defective product.

[0182] Based on this, in this embodiment, the mask to be discarded provided in step S0 can be divided into the following 6 types: (1) The mask to be discarded includes a mask substrate, a patternless mask material layer (including at least one patternless metal film, etc.) on the mask substrate, and a patternless photoresist on the mask material layer; (2) The mask to be discarded includes a mask substrate, a patterned mask material layer (including at least one patterned metal film, etc.) on the mask substrate, and a patterned photoresist on the mask material layer; (3) The mask to be discarded includes a mask substrate, a patterned mask material layer (including at least one patterned metal film, etc.) on the mask substrate. (4) The photomask to be discarded includes a photomask substrate and a patterned photomask material layer (including a patterned or unpatterned phase shift film and at least one patterned metal film) on the photomask substrate and a patterned photoresist on the photomask material layer; (5) The photomask to be discarded includes a photomask substrate, a patterned photomask material layer (including a patterned or unpatterned phase shift film and at least one patterned metal film) on the photomask substrate and a patterned photoresist on the photomask material layer; (6) The photomask to be discarded includes a photomask substrate and a photomask material layer (including a patterned or unpatterned phase shift film and at least one patterned metal film) on the photomask substrate. The metal film may include a stack of light-shielding films and anti-reflection films.

[0183] As an example, please refer to Figure 2 As shown, the mask to be discarded in step S0 is a binary blank mask that needs to be discarded. Specifically, it includes, from bottom to top, a mask substrate 101 (which can be a transparent substrate), a back anti-reflection film 103, a light-shielding film 104, and an anti-reflection film 105, stacked sequentially. The back anti-reflection film 103, the light-shielding film 104, and the anti-reflection film 105 are mask material layers located on the mask substrate 100. Areas where the back anti-reflection film 103, the light-shielding film 104, and the anti-reflection film 105 are stacked are opaque, while areas where they are not stacked are transparent, thus forming a pattern. The light-shielding film 104 can include one of CrN, CrC, and CrCN, and the back anti-reflection film 103 and the anti-reflection film 105 can include one of CrO, CrON, and CrCON.

[0184] As another example, please refer to Figure 3As shown, the mask to be discarded provided in step S0 is a phase-shift blank mask that needs to be discarded. Specifically, it includes, from bottom to top, a mask substrate 101 (which may be a transparent substrate), a phase-shifting film 102, a back anti-reflection film 103, a light-shielding film 104, and an anti-reflection film 105 stacked sequentially. The phase-shifting film 102, back anti-reflection film 103, light-shielding film 104, and anti-reflection film 105 constitute the mask material layer. Areas where the back anti-reflection film 103, light-shielding film 104, and anti-reflection film 105 are stacked are opaque, while areas where the back anti-reflection film 103, light-shielding film 104, and anti-reflection film 105 are not stacked are transparent, thereby forming a pattern. The material of the phase-shifting film 102 may include at least one of Cr compounds (e.g., chromium oxides, chromium nitrides, or chromium oxynitrides), MoSi, and MoSi compounds (e.g., MoSiON, MoSiCON, MoSiN, MoSiCN, or MoSiCO).

[0185] In summary, regardless of the type of mask provided in step S0 as the discarded mask, its overall structure includes a mask substrate and a mask material layer on the mask substrate. The mask substrate can be any one of a quartz substrate, a soda lime substrate, or a borosilicate substrate. Step S0 requires removing the mask material layer on the mask substrate and ensuring that the flatness (or surface roughness) of the top surface of the recycled mask substrate meets the requirements for manufacturing a new blank mask.

[0186] It should be understood that in step S0, any suitable laser surface treatment method can be used to remove all film layers on the mask substrate of the mask to be discarded, so that the top surface properties of the recycled mask substrate meet the requirements for manufacturing a new blank mask.

[0187] As an example, the laser surface treatment method used in step S0 is selected from the laser surface treatment methods that can be used in sub-step S13.

[0188] Specifically, please combine Figure 11 and Figure 12As shown, in step S0, a first laser is first used to perform laser removal on the discarded mask to remove the mask material layer on its mask substrate. Then, a second laser is used to perform laser polishing on the surface of the mask substrate, so that the surface roughness of the mask substrate meets the requirements for manufacturing a new blank mask. Optionally, in step S0, using sub-step S12, during the laser removal process of the discarded mask, the surface morphology of the discarded mask is detected online in real time. Based on the detection result, the process parameters for laser removal of the mask substrate surface (e.g., adjusting the wavelength, power, scanning path, focal length, focal plane, etc. of the first laser) are adjusted online in real time. Further optionally, in step S0, during the laser polishing process of the mask substrate, the surface morphology of the mask substrate is detected online in real time. Based on the detection result, the process parameters for laser polishing of the mask substrate surface (e.g., adjusting the wavelength, power, scanning path, focal length, focal plane, etc. of the first laser) are adjusted online in real time.

[0189] Therefore, by sequentially performing laser film removal, surface morphology detection, and laser polishing in step S0 and repeating these processes, it can be ensured that the recovered mask substrate can be directly used to manufacture new blank masks, thereby shortening the manufacturing cycle and reducing the manufacturing cost of blank masks.

[0190] After providing the required mask substrate in step S0, step S1 is executed first (i.e., steps S11 to S13 are executed repeatedly), and then a new blank mask with the required performance is manufactured based on the recycled mask substrate. Then step S2 is executed to perform laser direct writing on the blank mask.

[0191] Furthermore, the method of laser surface treatment of the discarded mask in step S0 is the same as the method of laser surface treatment of the new blank mask that does not meet the standards in sub-step S13. However, the film depth of the laser surface treatment in step S0 and sub-step S13 can be different.

[0192] It should also be understood that the laser film removal and laser polishing processes in steps S0 and S13 are basically the same as those in the second embodiment, and therefore will not be described in detail here.

[0193] Similarly, once the performance of a new blank mask is detected to be substandard in sub-step S12, the substandard new blank mask can be regarded as a mask to be discarded. Then, all or part of the process in the laser surface treatment in step S0 can be selected as sub-step S13 to rework or repair the substandard new blank mask according to the selected process (i.e., cyclically execute steps S11 to S13) until the performance of the new blank mask meets the standard.

[0194] In other words, compared to the second embodiment, the manufacturing method of this embodiment provides a discarded mask at the beginning. Therefore, the entire process starts from sub-step S13, that is, before the first pulsed laser deposition, sub-step S13 (i.e. step S0) is executed once to process the discarded mask into a mask substrate that can be used to manufacture a new blank mask. Then, sub-steps S11 to S13 can be executed repeatedly until the performance of the manufactured blank mask reaches the target. This reduces the manufacturing cost of the new blank mask and ensures its manufacturing yield, thereby reducing the manufacturing cost of the mask with the required pattern and ensuring the manufacturing yield of the mask with the required pattern.

[0195] Furthermore, the manufacturing system used to implement the mask manufacturing method of this embodiment can be the same as the mask manufacturing system in the second embodiment, and will not be described again here.

[0196] In summary, the mask manufacturing method of this embodiment, which involves the recycling and reuse of discarded mask stencils, can further reduce the manufacturing cost of blank mask stencils compared to the solution of the second embodiment.

[0197] The above description is only a description of preferred embodiments of the present invention and is not intended to limit the scope of the present invention in any way. Any changes or modifications made by those skilled in the art based on the above disclosure shall fall within the protection scope of the present invention.

Claims

1. A method for regenerating a mask substrate, characterized in that, include: A photomask to be recycled is provided, the photomask including a photomask substrate and a mask material layer located on the photomask substrate; A first laser is provided by a laser surface treatment device, and the first laser is used to perform laser removal on the mask to remove the mask material layer and obtain the mask substrate; The laser surface treatment device provides a second laser, different from the first laser, to perform laser polishing on the surface of the mask substrate until the surface roughness of the mask substrate meets the requirements. In the laser process of at least one of the laser removal and laser polishing, the surface morphology of the mask is detected online, and the process parameters of the laser process are adjusted online based on the results of the surface morphology detection. The laser surface treatment device time-division multiplexes mechanisms on the same optical path to transmit the first laser and the second laser onto the mask in a time-division manner. The mechanisms on the same optical path include a beam combining mechanism, a beam expanding mechanism, a focusing mechanism, and a scanning focusing mechanism. The beam combining mechanism is used to receive the first laser and the second laser in a time-division manner and emit the received first laser or the second laser at the same angle to the beam expanding mechanism. The focusing mechanism is used to focus the laser emitted by the beam expanding mechanism. The scanning focusing mechanism is used to control the laser emitted by the focusing mechanism to be incident on the mask, thereby realizing laser scanning of the mask.

2. The method for regenerating a mask substrate as described in claim 1, characterized in that, When the first laser is used to remove the mask, the first laser is focused onto the mask material layer at the corresponding position, causing the mask material layer at that position to melt and evaporate.

3. The method for regenerating a mask substrate as described in claim 1, characterized in that, During the laser film removal process, at least one of the process parameters of the first laser, including wavelength, power, focusing parameters, and scanning parameters, is adjusted online based on the surface morphology detection results; during the laser polishing process, at least one of the process parameters of the second laser, including wavelength, power, focusing parameters, and scanning parameters, is adjusted online based on the surface morphology detection results.

4. The method for regenerating a mask substrate as described in claim 1, characterized in that, When the second laser is used to perform laser polishing on the surface of the mask substrate, the second laser is focused onto the mask substrate at the corresponding position and breaks the chemical bonds in the surface material of the mask substrate at the position or destroys the crystal structure in the surface material at the position, thereby removing the surface material at the position.

5. The method for regenerating a mask substrate as described in any one of claims 1-4, characterized in that, The first laser is generated by an ultraviolet laser, a ruby ​​laser, an Nd glass laser, or an excimer laser.

6. The method for regenerating a mask substrate as described in any one of claims 1-4, characterized in that, The second laser is generated by a carbon dioxide laser.

7. The method for regenerating a mask substrate as described in any one of claims 1-4, characterized in that, The surface morphology of the mask is detected in real time using a scanning probe microscope.

8. A mask substrate regeneration system, characterized in that, include: A laser surface treatment apparatus is used to provide a first laser and use the first laser to perform laser removal on a mask to be recycled, so as to remove the mask material layer on the mask and obtain a mask substrate; and to provide a second laser different from the first laser and use the second laser to perform laser polishing on the surface of the mask substrate until the surface roughness of the mask substrate meets the requirements. A surface inspection unit is used to perform online surface morphology inspection on the mask during the laser process in which the laser surface treatment device performs at least one of the laser decoction and the laser polishing. The system's main control unit is coupled to the laser surface treatment device and the surface detection unit. It is used to control the coordinated operation of the laser surface treatment device and the surface detection unit, and to adjust the process parameters in the laser process online based on the surface morphology detection results. The laser surface treatment device time-division multiplexes mechanisms on the same optical path to transmit the first laser and the second laser onto the mask in a time-division manner. The mechanisms on the same optical path include a beam combining mechanism, a beam expanding mechanism, a focusing mechanism, and a scanning focusing mechanism. The beam combining mechanism receives the first laser and the second laser in a time-division manner and emits either the first laser or the second laser at the same angle to the beam expanding mechanism. The focusing mechanism focuses the laser emitted from the beam expanding mechanism. The scanning focusing mechanism controls the laser emitted from the focusing mechanism to be incident on the mask, thereby achieving laser scanning of the mask.

9. The regeneration system as described in claim 8, characterized in that, The laser surface treatment apparatus includes a first laser, a shutter, a quarter-wave plate, and a polarizer. The first laser is selected from an ultraviolet laser, a ruby ​​laser, an Nd glass laser, or an excimer laser. Alternatively, the laser surface treatment apparatus includes a second laser for generating a second laser, wherein the second laser is a carbon dioxide laser.

10. The regeneration system as claimed in claim 8, characterized in that, It also includes a support platform for carrying the mask to be recycled; the scanning and focusing mechanism includes a galvanometer, which consists of two reflectors respectively connected to a swing motor. The system's main control device controls the rotation of the reflectors by controlling the motors, so that the first laser or the second laser swings along a specific path, and in conjunction with the movement of the support platform, scans the mask.

11. The regeneration system as claimed in claim 10, characterized in that, The surface inspection unit includes a scanning probe microscope, which is integrated with the stage device and the laser surface treatment device at different positions on the same machine.

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