MASK, LITHOGRAPHIC APPARATUS, MASK MANUFACTURING METHOD, AND MASK-BASED LITHOGRAPHIC METHOD - Patent application

Abstract

The present disclosure relates to a mask, a lithography apparatus, a method for manufacturing a mask, and a mask-based lithography method, the mask comprising a substrate (110) configured to be transparent to an exposure beam (920) for lithography, the exposure beam (920) being in a first frequency band, the mask further comprising a photochromic layer (120) provided on one side of the substrate (110) and including a photochromic material, the photochromic layer configured to generate a corresponding mask pattern under irradiation with a modulated beam (930) having a spatial structure, the photochromic material being in a light-opaque or light-transmissive state with respect to the exposure beam depending on whether the photochromic material is irradiated with modulated light in the modulated beam (930), and the modulated beam (930) being in a second frequency band separated from the first frequency band.

Description

[Technical field]

[0001] (CROSS REFERENCE TO RELATED APPLICATIONS) This application claims priority to Chinese Patent Application No. 202210373932.5, entitled "MASK, LITHOGRAPHY APPARATUS, MANUFACTURING METHOD OF MASK, AND LITHOGRAPHY METHOD BASED ON MASK," filed on April 11, 2022, the entire disclosure of which is incorporated herein by reference.

[0002] The present disclosure relates generally to the technical field of lithography, and more particularly to a mask, a lithographic apparatus, a method for manufacturing a mask, and a mask-based lithographic method. [Background technology]

[0003] In lithography technology, pattern structures are typically formed using a mask. However, once the mask is prepared, the pattern on the mask cannot be easily changed. Moreover, if there is a defect in the mask or a defect occurs during the process using the mask, it is also difficult to repair the defect. In addition, masks are typically expensive. All of these above factors can lead to an increase in the cost of chips produced using the mask and a complication of the process due to monitoring the defects of the mask. Therefore, there is a need for new masks in chip production technology. Summary of the Invention

[0004] It is an object of the present disclosure to provide a mask, a lithographic apparatus, a method for manufacturing a mask, and a mask-based lithographic method.

[0005] According to a first aspect of the present disclosure, there is provided a mask comprising a substrate configured to be transparent to an exposure beam for lithography, the exposure beam being in a first frequency band, the mask further comprising a photochromic layer provided on one side of the substrate and including a photochromic material, the photochromic layer configured to generate a corresponding mask pattern under irradiation with a modulated beam having a spatial structure, the photochromic material being in a light-opaque or light-transmissive state to the exposure beam based on whether the photochromic material is irradiated with modulated light in the modulated beam, and the modulated beam being in a second frequency band separated from the first frequency band.

[0006] In some embodiments, the substrate comprises at least one of quartz or calcium fluoride.

[0007] In some embodiments, the photochromic material is configured to be in the light non-transmissive state to the exposure beam when irradiated with the modulated light in the modulated beam, and the photochromic material is configured to be in the light transmissive state to the exposure beam when not irradiated with the modulated light in the modulated beam.

[0008] In some embodiments, the photochromic material is configured to be in the light-transmitting state to the exposure beam when irradiated with the modulated light in the modulated beam, and the photochromic material is configured to be in the light-non-transmitting state to the exposure beam when not irradiated with the modulated light in the modulated beam.

[0009] In some embodiments, when the photochromic material is in the light transmitting state, the transmittance of the exposure beam is between 60% and 99%.

[0010] In some embodiments, when the photochromic material is in the light non-transmitting state, the transmittance of the exposure beam is between 5% and 30%.

[0011] In some embodiments, the wavelengths corresponding to the first frequency band include 193 nm to 405 nm.

[0012] In some embodiments, the wavelengths corresponding to the first frequency band include at least one of 193 nm, 248 nm, 325 nm, 365 nm, or 405 nm.

[0013] In some embodiments, the wavelengths corresponding to the second frequency band include 500 to 580 nm or 580 to 1100 nm, or a portion of 500 to 580 nm or a portion of 580 to 1100 nm.

[0014] In some embodiments, the wavelength corresponding to the second frequency band includes 633 nm.

[0015] In some embodiments, the photochromic layer comprises a photochromic material in the form of a continuous film.

[0016] In some embodiments, the thickness of the photochromic layer is 50 to 200 nm or 200 to 5000 nm.

[0017] In some embodiments, the photochromic material includes at least one of an organic photochromic material or an inorganic photochromic material.

[0018] In some embodiments, the photochromic material comprises 1,2-bis(5,5'-dimethyl-2,2'-bithiophen-yl)perfluorocyclopent-1-ene.

[0019] In some embodiments, the mask further includes a modulated light source configured to generate a modulated beam having a spatial structure.

[0020] In some embodiments, the modulated light source comprises a first light generator configured to generate an initial beam in a second frequency band, the initial beam having a uniform light intensity distribution in a cross section perpendicular to its propagation direction, and the modulated light source further comprises a spatial light modulator configured to convert the initial beam into the modulated beam having the spatial structure under the action of a control signal, the control signal being generated based on a mask pattern.

[0021] In some embodiments, the modulated beam is a near field beam relative to the photochromic layer.

[0022] In some embodiments, the mask further comprises a temperature controller comprising a temperature maintaining unit configured to be disposed adjacent to the mask or the photochromic layer to maintain the temperature of the mask within a preset temperature range.

[0023] According to a second aspect of the present disclosure, there is provided a lithographic apparatus comprising: a mask as described above; and a control module configured to generate control signals according to a design layout, said control signals being used to generate a modulated beam having a spatial structure corresponding to said design layout.

[0024] In some embodiments, the lithographic apparatus further comprises a modulated light source configured to generate the modulated beam having the spatial structure.

[0025] In some embodiments, the modulated light source comprises a first light generator configured to generate an initial beam in a second frequency band, the initial beam having a uniform light intensity distribution in a cross section perpendicular to its propagation direction, and the modulated light source further comprises a spatial light modulator configured to convert the initial beam into the modulated beam having the spatial structure under the action of a control signal, the control signal being generated according to a mask pattern.

[0026] In some embodiments, the lithographic apparatus further comprises a temperature controller, the temperature controller comprising a temperature maintaining unit configured to be provided adjacent to the mask or the photochromic layer to maintain the temperature of the mask within a preset temperature range.

[0027] In some embodiments, the lithographic apparatus further comprises a second light generator configured to generate an exposure beam in the first frequency band.

[0028] In some embodiments, the exposure beam has a uniform light intensity distribution on a cross section perpendicular to its propagation direction.

[0029] According to a third aspect of the present disclosure, there is provided a method for manufacturing a mask, comprising: providing a substrate, the substrate configured to be transparent to an exposure beam for lithography, the exposure beam being in a first frequency band; and forming a photochromic layer on one side of the substrate, the photochromic layer comprising a photochromic material and configured to generate a corresponding mask pattern under irradiation with a modulated beam having a spatial structure, the photochromic material being in a light-opaque or light-transmissive state to the exposure beam based on whether the photochromic material is irradiated with modulated light in the modulated beam, and the modulated beam being in a second frequency band separated from the first frequency band.

[0030] According to a fourth aspect of the present disclosure, there is provided a lithography method based on the above-mentioned mask, comprising: irradiating a modulated beam having a spatial structure onto the mask to generate a corresponding mask pattern on the mask, irradiating the exposure beam onto a wafer through the mask to expose the wafer after the mask pattern is generated, turning off the exposure beam after the wafer is exposed, and turning off the modulated beam after turning off the exposure beam.

[0031] In some embodiments, the intensity of the modulated beam is greater than the intensity of the exposure beam.

[0032] In some embodiments, the lithographic method further comprises operating a temperature controller to maintain a temperature of the mask within a preset temperature range.

[0033] The accompanying drawings, which constitute a part of this specification, illustrate embodiments of the present disclosure and, together with the description, serve to explain the principles of the disclosure.

[0034] The present disclosure may be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which: [Brief description of the drawings]

[0035] [Figure 1] FIG. 1 is a structural schematic diagram of a mask according to an exemplary embodiment of the present disclosure.

[0036] [Diagram 2] FIG. 2 is a schematic diagram of a mask being illuminated with an exposure beam and a modulated beam according to an exemplary embodiment of the present disclosure.

[0037] [Diagram 3] FIG. 3 is a schematic cross-sectional view of a mask being irradiated with an exposure beam and a modulated beam according to an exemplary embodiment of the present disclosure.

[0038] [Figure 4] FIG. 4 is a structural schematic diagram of a lithographic apparatus according to an exemplary embodiment of the present disclosure.

[0039] [Diagram 5] FIG. 5 is a schematic flow diagram of a method for manufacturing a mask according to an exemplary embodiment of the present disclosure.

[0040] [Figure 6] FIG. 6 is a schematic flow diagram of a mask-based lithography method according to an exemplary embodiment of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0041] The present disclosure will be described below with reference to the accompanying drawings showing some embodiments of the present disclosure. However, it should be understood that the present disclosure can be presented in many different forms and is not limited to the embodiments described below. Indeed, the embodiments described below are intended to make the disclosure of the present disclosure more complete and fully convey the scope of protection of the present disclosure to those skilled in the art. It should also be understood that the embodiments disclosed herein can be combined in various ways to provide many additional embodiments.

[0042] It should be understood that like reference numerals represent like elements in all drawings, and in the drawings, the size of certain features may be distorted for clarity.

[0043] It should be understood that the terms in this specification are used only to describe certain embodiments and are not intended to limit the present disclosure. All terms (including technical and scientific terms) used in this specification have the meanings commonly understood by those skilled in the art unless otherwise defined. For the sake of brevity and / or clarity, well-known functions or structures may not be described in detail.

[0044] As used herein, the terms "comprising," "comprising," and "containing" indicate the presence of a stated feature but do not exclude the presence of one or more other features. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items. As used herein, the terms "between X and Y" and "between about X and Y" should be interpreted to include X and Y. As used herein, the term "between about X and Y" means "between about X and about Y," and the term "about X to Y" as used herein means "about X to about Y."

[0045] As used herein, when an element is described as being "on," "attached," "connected," "coupled," or "in contact with" another element, the element may be directly on, attached, connected, coupled, or in contact with the other element, although intermediate elements may be present. In contrast, when an element is described as being "directly on," "directly attached," "directly connected," "directly coupled," or "in direct contact with" another element, intermediate elements are not present. As used herein, a feature located "adjacent" to another feature may refer to the feature having an overlap with the adjacent feature or being located above or below the adjacent feature.

[0046] As used herein, spatial relationship terms such as "above," "below," "left," "right," "front," "back," "high," and "low" may describe the relationship between one feature and another feature in the accompanying drawings. It should be understood that the spatial relationship terms encompass different orientations of the device in use or operation in addition to the orientation shown in the drawings. For example, when a device in the drawings is inverted, a feature that would otherwise be described as being "below" another feature may then be described as being "above" that other feature. The device may also be otherwise oriented (rotated 90 degrees or otherwise) and the relative spatial relationships may be interpreted accordingly.

[0047] In the research of micro-nano devices and the manufacturing process of semiconductor chips, the structure of a desired device or chip is typically formed using a mask-based lithography technique. To form the desired structure, one or more masks may be fabricated in advance according to the layout of the device or chip to be processed and in light of the corresponding processing procedure. In this case, the pattern on each mask may correspond to one layer in the layout or multiple layers that can be prepared in the same procedure. Typically, the mask may comprise a substrate (e.g., quartz glass) that can transmit an exposure beam (e.g., ultraviolet light) to change the properties of the resist (photoresist), and a plating film (e.g., metal chrome film) deposited on the substrate to prevent the exposure beam from passing through.

[0048] In the method for manufacturing a mask, a chromium film having a thickness of several tens of nanometers and a resist placed on the chromium film can be successively deposited on a quartz glass, and then a desired pattern can be formed on the resist by direct laser writing or electron beam exposure, and then the chromium exposed from the resist can be wet-etched or dry-etched to form a pattern corresponding to a desired structure on the chromium film. The direct laser writing method is typically used to form a mask having a minimum line width larger than 300 nm, and the electron beam exposure method can be used to form a mask having a minimum line width less than 300 nm.

[0049] Using the above preparation method, the cost of just one mask is about tens of thousands of dollars, and the cost of a complete set of masks for the production process of devices or chips can reach millions of dollars. Moreover, once such a mask is prepared, it is difficult to change its structure. In traditional application scenarios, the single batch quantity of chips including CPUs, DRAMs, flash memories, and the like is typically on the order of millions or even hundreds of millions, so the mask fabrication cost can be fully shared, and the mask-based lithography process can be widely applied to the fabrication and production of these devices or chips. However, with the development of industries such as IoT, artificial intelligence, and personalized medicine, small batch production of devices or chips is increasingly required, and the number of these devices or chips may be only tens of thousands or even less. If a mask is prepared in advance and these devices or chips are produced based on the mask, it becomes difficult to share the cost of mask fabrication by a sufficient number of devices or chips, and as a result, the cost of the devices or chips increases greatly. In addition, when these devices or chips are directly fabricated by laser direct writing, the yield is too low to meet the requirements of mass production, while the minimum line width of laser direct writing, which is about 300 nm, also restricts the improvement of chip integration and performance and the reduction of chip cost by miniaturizing the device. Similarly, when these devices or chips are directly fabricated by electron beam exposure, although it is possible to fabricate smaller and more integrated devices or chips, the yield is still too low to meet the requirements of production volume and the processing cost is very high, which prevents the penetration of these devices and chips into the market.

[0050] In addition, defects in a mask can also significantly increase the production costs of a device or chip: if a small defect is present in a mask, time must be spent to detect and repair the defect, and if a large defect is present in a mask, the entire mask may have to be discarded.

[0051] In order to solve the above problems and meet the requirements of small batch production of chips and high integration of related products, so that future technologies such as IoT and artificial intelligence can be better penetrated into society, the present disclosure provides a programmable, rewritable and even reusable digital lithography mask, in which the light transmission state of the corresponding pixel area of ​​the mask can be reversibly changed by controlling the modulated beam with spatial structure irradiated on the mask with photochromic material, so that the pattern on the same mask can be changed as needed, thereby realizing the reuse of the mask and further reducing the production cost of the device or chip.

[0052] In an exemplary embodiment of the present disclosure, the mask comprises a substrate 110 and a photochromic layer 120, as shown in FIG.

[0053] The substrate 110 may be configured to be transparent to the exposure beam for lithography to avoid interference with the lithography process. The exposure beam may be in a first frequency band, which typically corresponds to a frequency band in which partial ultraviolet light is located. For example, the wavelengths corresponding to the first band may include 193-405 nm. In some implementations, the wavelengths corresponding to the first band may include at least one of 193 nm, 248 nm, 325 nm, 365 nm, or 405 nm. The substrate 110 may be made of a material that has a certain structural strength to support other layers of the mask disposed thereon. In some embodiments, the substrate 110 may be made of quartz glass, calcium fluoride glass, or the like.

[0054] The photochromic layer 120 may be provided on one side of the substrate 110, and the photochromic layer 120 may contain a photochromic material and generate a corresponding mask pattern under irradiation with a modulated beam having the above-mentioned spatial structure. As shown in Figures 2 and 3, the modulated beam 930 having a spatial structure specifically refers to a beam having a non-uniform intensity distribution on a cross section perpendicular to its traveling direction. For example, in a cross section perpendicular to the traveling direction of the modulated beam 930, the intensity of the modulated light in some areas may be zero, while the intensity of the modulated light in other areas may not be zero. The photochromic material is in a light-opaque or light-transmissive state with respect to the exposure beam depending on whether the photochromic material is irradiated with the modulated light in the modulated beam, and thus a light-opaque and light-transmissive region is formed in the mask, thereby forming a desired mask pattern.

[0055] In a specific example, when the photochromic material faces a region on the cross section of the modulated beam 930 where the intensity of the modulated light is not zero, i.e., when the photochromic material is irradiated with the modulated light in the modulated beam 930, this portion of the photochromic material absorbs the modulated light and becomes non-transmissive to the exposure beam (e.g., an organic photochromic material absorbs the modulated light as de-excitation light and generates a high absorption rate for the ultraviolet light in the exposure beam. As a result, this portion of the organic photochromic material becomes non-transmissive to the exposure beam), which corresponds to the non-transmissive region 122 of the photochromic material for the exposure beam 920 shown in Figure 3. And when the photochromic material faces a region on the cross section of the modulated beam 930 where the intensity of the modulated light is zero, i.e., when the photochromic material is not irradiated with the modulated light in the modulated beam 930, this portion of the photochromic material becomes transmissive to the exposure beam, which corresponds to the transmissive region 121 of the photochromic material for the exposure beam 920 shown in Figure 3. Therefore, by controlling the spatial distribution of the intensity of the modulated beam or by controlling the spatial structure of the modulated beam, light-transmitting regions 121 and light-non-transmitting regions 122 for the exposure beam 920 can be formed in the photochromic layer 120, and further, by combining these regions, a desired mask pattern can be formed on the mask.

[0056] Of course, it should be understood that in some other embodiments, when the photochromic material faces an area on the cross-section of the modulated beam where the intensity of the modulated light is non-zero, i.e., when the photochromic material is irradiated with the modulated light in the modulated beam, this portion of the photochromic material will be in a light-transmitting state to the exposure beam, and when the photochromic material faces an area on the cross-section of the modulated beam where the intensity of the modulated light is zero, i.e., when the photochromic material is not irradiated with the modulated light in the modulated beam, this portion of the photochromic material will be in a light-opaque state to the exposure beam.

[0057] Moreover, in general, the light non-transmitting (or light transmitting) state of the photochromic material can only be maintained when the modulated light is irradiated on the photochromic material, and once the modulated light is removed, the photochromic material regains its original state. Therefore, when performing lithography with a mask containing such a photochromic material, it is necessary to continue irradiating the modulated beam on the mask while exposing the wafer / sample with the exposure beam in order to keep the light transmitting and light non-transmitting areas of the mask unchanged or to keep the mask pattern unchanged until the lithography is completed. The above requirement requires that the modulated beam 930 avoids interference with the exposure process, i.e., the modulated beam 930 cannot change the properties of the resist (e.g., photoresist). This requires that the modulated beam 930 is in a second frequency band separated from the first frequency band for the exposure beam 920. Here, the separated first and second frequency bands refer to any frequency in the first frequency band being different from any frequency in the second frequency band. In some embodiments, the wavelength corresponding to the second frequency band can include 500-580 nm or 580-1100 nm, or a portion of 500-580 nm or a portion of 580-1100 nm. In one specific example, the wavelength corresponding to the second frequency band can be 633 nm.

[0058] In order to ensure that the photochromic material of the mask can transmit enough of the exposure beam to expose the sample when in the light-transmitting state, and can block enough of the exposure beam to avoid exposing the wafer / sample when in the non-light-transmitting state, the transmittance of the photochromic material in the light-transmitting and non-light-transmitting states must meet certain requirements. In one embodiment, when the photochromic material is in the light-transmitting state, its transmittance to the exposure beam can be 60%-99%, and when the photochromic material is in the non-light-transmitting state, its transmittance to the exposure beam can be 5%-30%.

[0059] In some embodiments, the photochromic material may comprise at least one of an organic photochromic material and an inorganic photochromic material. Typical organic photochromic materials may include tetracene solution, benzalphenylhydrazine solution, osazone solution, or the like in liquid form, and 2,3,4,4-tetrachloronaphthalene-1-(4H)-one, spiro naphthoxazine-based organic materials, diarylethene-based materials, azobenzene derivatives, 1,2-bis(5,5'-dimethyl-2,2'-bithiophen-yl)perfluorocyclopent-1-ene, or the like in solid form. Meanwhile, inorganic photochromic materials may include tungsten oxide (WO x The oxides may include various transition metal oxides and their composites, such as molybdenum trioxide (MoO3), vanadium pentoxide (V2O5), and titanium dioxide (TiO2).

[0060] However, in current lithography applications, it is generally considered that a usable photochromic material should at least have the following properties: (1) The light-transmitting state and the light-non-transmitting state of the photochromic material can be reversibly switched under the control of the modulated beam to realize a rewritable and reusable mask. That is, when not irradiated with the modulated light in the modulated beam, the photochromic material has a sufficiently high transmittance to the exposure beam in the first frequency band, and when irradiated with the modulated light in the modulated beam, the photochromic material has a sufficiently low transmittance to the exposure beam in the first frequency band. Alternatively, when not irradiated with the modulated light in the modulated beam, it has a sufficiently low transmittance to the exposure beam in the first frequency band, and when irradiated with the modulated light in the modulated beam, it has a sufficiently high transmittance to the exposure beam in the first frequency band. (2) The second frequency band in which the modulated beam for reversibly switching the light-transmitting state and the light-non-transmitting state of the photochromic material is located is separated from the first frequency band in which the exposure beam (ultraviolet light) is located to avoid interference with the lithography process. In view of the above considerations, in the existing lithography process using ultraviolet light as the exposure beam, 1,2-bis(5,5'-dimethyl-2,2'-bithiophene-yl)perfluorocyclopent-1-ene may be used as the photochromic material of the mask. However, it should be understood that when the exposure beam or the modulated beam in another frequency band is used, other photochromic materials corresponding to the corresponding frequency band may be selected, and the present specification is not limited thereto. Furthermore, by selecting a photochromic material that has good heat dissipation and requires a low intensity modulated beam, a significant increase in the mask temperature caused by the irradiation of the modulated beam can be reduced, thereby improving the reliability of the lithography.

[0061] In general, the photochromic layer 120 may include a photochromic material in the form of a continuous film to facilitate preparation of the mask by deposition means such as lamination, spin-coating, and spraying. In order for the photochromic material to be able to effectively block the exposure beam in a non-light-transmitting state, the photochromic layer 120 may have a thickness of 50-200 nm or 200-5000 nm. In some other examples, a patterned photochromic layer may be formed as required, and the patterned photochromic layer may be formed by laser direct writing, electron beam direct writing, and other mask-based lithography, or the like. Alternatively, in some other examples, a liquid photochromic material may be used as required, and a blocking layer may be further provided above the photochromic layer 120, so that the liquid photochromic material is restricted between the substrate 110 and the blocking layer, maintaining the stability of the mask structure, thereby ensuring the effect of the exposure.

[0062] In some embodiments, as shown in FIG. 4, a modulated light source 200 may be included, which may be considered as part of the mask or may be provided in the lithography apparatus including the mask independently of the mask. The modulated light source 200 may be configured to generate a modulated beam having a spatial structure. Specifically, the modulated light source 200 may include a first light generator 210 and a spatial light modulator 220, where the first light generator 210 may be configured to generate an initial beam in a second frequency band, the initial beam having a uniform light intensity distribution on a cross section perpendicular to the traveling direction of the initial beam, and the spatial light modulator 220 may be configured to convert the initial beam having the spatial structure into a modulated beam under the action of a control signal generated according to a mask pattern. The spatial structure of the modulated beam corresponds to a desired mask pattern, and the modulated beam irradiated on the photochromic material on the mask forms corresponding light-transmitting or light-non-transmitting regions. In some embodiments, the spatial light modulator may be an optical phase modulator.

[0063] In one embodiment, the spatial light modulator can achieve a pixel count of 4160 x 2464 and a pixel period of 3.74 μm. By using such a spatial light modulator and a modulated beam with a wavelength of 633 nm, a pattern consisting of minute light spots with a size of 3 to 4 μm and a period of 6 to 8 μm can be formed on a mask. By using such a mask in combination with a 4x reduction projection lithography technique, the minimum processable line width can be reduced to about 1 μm, and the area of ​​a single exposure can be reduced to 1 x 1 cm. 2 In the case of projection exposure, assuming a single exposure time of 100 ms, the lithography yield of such a mask is 600 cm 2 It is calculated that the yield can reach 10 ... In addition, the mask of the present disclosure may be limited by the diffraction effect of the modulated beam, and the minimum line width on the mask is typically around 400 nm; however, by combining projection lithography with a higher demagnification ratio, e.g., 10x demagnification projection lithography technology, and performing exposure using, e.g., a deep ultraviolet (DUV) exposure beam of 193 nm, the minimum lithographic line width can be further improved to below 45 nm, meeting the production requirements of advanced chips.

[0064] Furthermore, in the lithography process, the exposure beam generated by the second light generator 300 may be a near-field beam with respect to the mask to improve the lithography accuracy and improve the accuracy of the lithography pattern. Similarly, the modulated beam generated by the modulated light source 200 may be a near-field beam with respect to the photochromic layer of the mask to avoid the impact on accuracy caused by the optical diffraction effect of the far-field beam and improve the accuracy of the mask pattern.

[0065] In some embodiments, considering that the modulated beam for controlling the light-transmitting or non-light-transmitting state of the photochromic material typically has a high optical power, a temperature controller 400 may be further provided to avoid excessively strong light being irradiated onto the mask or sample, which may result in an increase in the temperature of the mask or sample, as shown in FIG. 4. The temperature controller 400 may be considered to be included in the mask, or may be considered to be provided independently of the mask in a lithography apparatus including the mask. The temperature controller 400 may include a temperature maintaining unit. The temperature maintaining unit may be configured to be provided adjacent to the substrate 110 or the photochromic layer 120 to maintain the temperature of the mask within a preset temperature range. The temperature controller may be a liquid cooling temperature controller, a thermoelectric semiconductor temperature controller, etc., but is not limited thereto in the present specification. In general, the light intensity of the exposure beam required in the exposure process is typically 10 to 10,000 mW / cm. 2 whereas the light intensity of the modulated beam for changing the light transmission state of the photochromic material is typically 10 to 10,000 W / cm 2For example, during a lithography process, the light intensity of a modulated beam having a wavelength of 633 nm may be more than 1000 times greater than the light intensity of an exposure beam having a wavelength of 325 nm. By using the temperature controller 400 to keep the mask within a preset temperature range, it is possible to prevent the mask from being damaged under the action of the strong modulated beam, and to convert the photochromic material in the mask into a photochromic material having a higher intensity (e.g., 100 kW / cm2). 2 ) can be used to excite the photochromic material to rapidly change its light transmission state, even to the extent that it is ideally suited to obtain the desired transmission.

[0066] In the mask of the present disclosure, the reversible change of the light transmission state of each pixel region can be controlled by using the photochromic material therein. Thus, the corresponding mask pattern can be directly formed based on the data file of the required structure of the device or chip, and the mask pattern on the same mask can be erased and rewritten. This can realize the reuse of the mask, improve the utilization efficiency of the mask, reduce the fabrication cost of the device or chip, and avoid a series of problems caused by the high cost of the mask in traditional lithography.

[0067] In an exemplary embodiment of the present disclosure, a lithography apparatus is also provided. The lithography apparatus may include the mask body 100 and a control module 500 as described above, as shown in FIG. 4. In some embodiments, the lithography apparatus may further include at least one of the modulated light source 200 as described above, the second light generator 300 configured to generate an exposure beam in a first frequency band (the exposure beam typically has a uniform light intensity distribution on a cross section perpendicular to its traveling direction, or has a uniform light intensity distribution at least in a central region of the cross section), or the temperature controller 400 as described above. The control module 500 may be configured to generate control signals according to a layout for generating a modulated beam having a spatial structure corresponding to the layout. In particular, the control module 500 may be configured to generate a plurality of mask patterns corresponding to one or more layers in a layout of a device or chip, and generate corresponding control signals according to each mask pattern. In addition, the control module 500 communicates the control signals to the spatial light modulator 220, which in turn causes the spatial light modulator 220 to change the light transmission state of individual pixel regions of the mask.

[0068] In the lithography apparatus of the embodiment of the present disclosure, the data file of the pattern to be exposed can be used to directly manufacture a corresponding reversible mask. By combining 10x reduction projection technology and LELE (Litho-Etch-Litho-Etch) technology and similar technologies, the lithography apparatus can meet the small batch production requirements of chips of 14nm or even more advanced process nodes. The fabrication of a complex device or chip can be efficiently and accurately completed through only one or a few reusable and rewritable masks, which reduces the fabrication cost of the device or chip and facilitates the rapid update, mass production, and better market penetration of the device or chip.

[0069] In an exemplary embodiment of the present disclosure, a method for manufacturing a mask is also provided, which may include the following steps, as shown in FIG. A step S610 of providing a substrate; A photochromic layer is formed on the substrate, step S620. Here, the substrate may be configured to be transparent to an exposure beam for lithography, the exposure beam being in a first frequency band, the photochromic layer may comprise a photochromic material and may be configured to generate a corresponding mask pattern under irradiation with a modulated beam having a spatial structure, the photochromic material being in a light non-transmitting or light transmitting state to the exposure beam based on whether the photochromic material is irradiated with modulated light in the modulated beam, and the modulated beam being in a second frequency band separated from the first frequency band.

[0070] In an exemplary embodiment of the present disclosure, a mask-based lithography method as described above is also provided, which may include, as shown in FIG. Step S710 of illuminating a modulated beam having a spatial structure onto a mask to generate a corresponding mask pattern on the mask; After the mask pattern is generated, step S720 involves projecting an exposure beam through the mask onto the photoresist-coated wafer / sample to expose the wafer; After exposure of the wafer / sample, step S730 turns off the exposure beam; After turning off the exposure beam, the modulation beam is turned off, step S740.

[0071] In other words, the modulated beam needs to be kept on during the entire exposure process to ensure the correctness of the mask pattern. The intensity of the modulated beam may be greater than the intensity of the exposure beam. Correspondingly, the above lithography method may further include operating a temperature controller to maintain the temperature of the mask within a proposed temperature range.

[0072] Although exemplary illustrative embodiments of the present disclosure have been described, those skilled in the art will understand that numerous variations and modifications may be made to the exemplary embodiments of the present disclosure without essentially departing from the spirit and scope of the present disclosure. Therefore, all such variations and modifications are included within the scope of protection of the present disclosure as defined in the claims. The present disclosure is defined by the appended claims, and the equivalents of these claims are also included therein.

Claims

1. A mask, the mask comprising: a substrate configured to be transparent to an exposure beam for lithography, the exposure beam being in a first waveband, the mask further comprising: A mask comprising a photochromic layer disposed on one side of the substrate and including a photochromic material, the photochromic layer configured to generate a corresponding mask pattern under irradiation with a modulated beam having a spatial structure, the photochromic material being in a light non-transmissive state or a light transmissive state to the exposure beam based on whether the photochromic material is irradiated with modulated light in the modulated beam, and the modulated beam being in a second frequency band separated from the first frequency band.

2. The mask of claim 1 , wherein the substrate comprises at least one of quartz or calcium fluoride.

3. the photochromic material is configured to be in the light non-transmissive state to the exposure beam when irradiated with the modulated light in the modulated beam; and 2. The mask of claim 1, wherein said photochromic material is configured to be in said light transmissive state to said exposure beam when not illuminated by said modulated light in said modulated beam.

4. the photochromic material is configured to be in the light transmissive state to the exposure beam when illuminated with the modulated light in the modulated beam; and 2. The mask of claim 1, wherein the photochromic material is configured to be in the optically non-transmissive state to the exposure beam when not illuminated by the modulated light in the modulated beam.

5. 2. The mask of claim 1, wherein said photochromic material has a transmittance to said exposure beam of between 60% and 99% when in said light transmitting state.

6. 2. The mask of claim 1, wherein said photochromic material has a transmittance to said exposure beam of between 5% and 30% when in said non-light-transmitting state.

7. 2. The mask of claim 1, wherein the wavelengths corresponding to the first frequency band include 193 nm to 405 nm.

8. 2. The mask of claim 1, wherein wavelengths corresponding to the first frequency band include at least one of 193 nm, 248 nm, 325 nm, 365 nm, or 405 nm.

9. 2. The mask of claim 1, wherein the wavelengths corresponding to the second waveband include 500-580 nm or 580-1100 nm, or a portion of 500-580 nm or a portion of 580-1100 nm.

10. 2. The mask of claim 1, wherein wavelengths corresponding to the second frequency band include 633 nm.

11. The mask of claim 1 , wherein the photochromic layer comprises a photochromic material in the form of a continuous film.

12. The mask of claim 1, wherein the photochromic layer has a thickness of 50 to 200 nm or 200 to 5000 nm.

13. The mask of claim 1 , wherein the photochromic material comprises at least one of an organic photochromic material or an inorganic photochromic material.

14. 2. The mask of claim 1, wherein the photochromic material comprises 1,2-bis(5,5'-dimethyl-2,2'-bithiophen-yl)perfluorocyclopent-1-ene.

15. The mask comprises: The mask of claim 1 , further comprising a modulated light source configured to generate a modulated beam having a spatial structure.

16. The modulated light source includes: a first light generator configured to generate an initial beam in a second frequency band, the initial beam having a uniform light intensity distribution in a cross section perpendicular to a direction of propagation of the initial beam; and the modulated light source further comprising:

16. The mask of claim 15, comprising a spatial light modulator configured to convert the initial beam into the modulated beam having the spatial structure under the action of a control signal, the control signal being generated based on a mask pattern.

17. The mask of claim 1 , wherein the modulated beam is a near field beam with respect to the photochromic layer.

18. The mask comprises:

10. The mask of claim 1, further comprising a temperature controller, the temperature controller comprising a temperature maintaining unit configured to be disposed adjacent the mask or the photochromic layer to maintain a temperature of the mask within a preset temperature range.

19. 1. A lithographic apparatus comprising: A mask according to any one of claims 1 to 14; 1. A lithographic apparatus comprising: a control module configured to generate control signals according to a layout, the control signals being used to generate a modulated beam having a spatial structure corresponding to the layout.

20. the lithographic apparatus comprising:

20. The lithographic apparatus of claim 19, further comprising a modulated light source configured to generate the modulated beam having the spatial structure.

21. The modulated light source includes: a first light generator configured to generate an initial beam in a second frequency band, the initial beam having a uniform light intensity distribution in a cross section perpendicular to a direction of propagation of the initial beam; and the modulated light source further comprising:

21. The lithographic apparatus of claim 20, further comprising a spatial light modulator configured to transform the initial beam into the modulated beam having the spatial structure under the action of the control signal, the control signal being generated according to a mask pattern.

22. the lithographic apparatus comprising:

20. The lithographic apparatus of claim 19, further comprising a temperature controller, the temperature controller comprising a temperature maintaining unit configured to be provided adjacent the mask or the photochromic layer to maintain a temperature of the mask within a preset temperature range.

23. the lithographic apparatus comprising:

20. The lithographic apparatus of claim 19, further comprising a second light generator configured to generate an exposure beam in the first frequency band.

24. 24. The lithographic apparatus of claim 23, wherein the exposure beam has a uniform light intensity distribution on a cross section perpendicular to its propagation direction.

25. 1. A lithographic apparatus comprising: A mask according to any one of claims 15 to 18; 1. A lithographic apparatus comprising: a control module configured to generate control signals according to a layout, the control signals being used to generate a modulated beam having a spatial structure corresponding to the layout.

26. 1. A method for manufacturing a mask, the method comprising the steps of: providing a substrate, the substrate being configured to be transparent to an exposure beam for lithography, the exposure beam being in a first waveband; forming a photochromic layer on one side of the substrate, the photochromic layer comprising a photochromic material and configured to generate a corresponding mask pattern under irradiation with a modulated beam having a spatial structure, the photochromic material being in a light-opaque or light-transmissive state to the exposure beam based on whether the photochromic material is irradiated with modulated light in the modulated beam, and the modulated beam being in a second frequency band separated from the first frequency band.

27. A lithography method based on a mask, the mask being according to any one of claims 1 to 18, comprising the steps of: illuminating a modulated beam having a spatial structure onto the mask to generate a corresponding mask pattern on the mask; After generating the mask pattern, projecting the exposure beam through the mask onto the sample to expose the sample; turning off the exposure beam after exposing the sample; turning off the modulated beam after turning off the exposure beam.

28. 28. The lithographic method of claim 27, wherein an intensity of the modulated beam is greater than an intensity of the exposure beam.

29. 28. The lithographic method of claim 27, further comprising operating a temperature controller to maintain a temperature of the mask within a preset temperature range.

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