Photolithography mask generation for obtaining a metal lens

Abstract

In the example, a target design for a metalens is obtained. The target design includes target design metaatoms. Based on the regional shift of the metalens' planned metaatoms relative to the target design metaatoms, one or more processors generate a mask design. The mask design may be generated using rule-based corrections, such as using a lookup table (LUT) in some examples, and using model-based corrections in others.

Description

Technical Field

[0001] Related Applications This application claims priority to and the benefit of U.S. Provisional Patent Application No. 63 / 487,360, filed Feb. 28, 2023, which is hereby incorporated by reference in its entirety.

[0002] This disclosure relates to generating a photolithography mask for manufacturing a metalens.

Background Art

[0003] A metalens is generally a planar lens that manipulates the phase, amplitude, and / or polarization of light to focus light. A metalens can manipulate the phase, amplitude, and / or polarization of light rather than using refraction to focus light. A metalens uses sub-resolution features to manipulate the phase, amplitude, and / or polarization of light and the lens focus. Various structures may be used inside the metalens to manipulate the phase, amplitude, and / or polarization as desired. A metalens may have applications such as virtual reality and augmented reality.

Summary of the Invention

[0004] This disclosure will be more fully understood from the detailed description given below and the accompanying drawings of embodiments of the disclosure. The figures are used to provide knowledge and understanding of embodiments of the disclosure but do not limit the scope of the disclosure to these specific embodiments. Further, the figures are not necessarily drawn to scale.

Brief Description of the Drawings

[0005] [Figure 1] A diagram of a method of manufacturing a metalens by way of several examples. [Figure 2] A diagram of an environment in which a metalens is manufactured. [Figure 3A]Perspective views and layout diagrams, respectively, of target-designed meta-atoms according to several examples. [Figure 3B] Perspective views and layout diagrams, respectively, of target-designed meta-atoms according to several examples. [Figure 4A] Perspective views and layout diagrams, respectively, of fabricated meta-atoms according to several examples. [Figure 4B] Perspective views and layout diagrams, respectively, of fabricated meta-atoms according to several examples. [Figure 5] Diagram of a first method for generating the mask design of FIG. 1 according to several examples. [Figure 6] Diagram of a second method for generating the mask design of FIG. 1 according to several examples. [Figure 7] Diagram of an example showing several operations of the second method of FIG. 6. [Figure 8] Diagram depicting an exemplary computer system in which exemplary procedures of the present disclosure can function.

Mode for Carrying Out the Invention

[0006] Aspects of the present disclosure relate to generating a photolithography mask for manufacturing a metalens. According to several examples, when generating a photolithography mask for manufacturing a metalens, the area of the to-be-fabricated subwavelength nano-structure inside the metalens is considered. Subwavelength nano-structures are generally structures that manipulate the phase, amplitude, and / or polarization of light passing through each subwavelength nano-structure of the metalens when fabricated. Hereinafter, subwavelength nano-structures may also be referred to as meta-atoms. A metalens can be manufactured using photolithography and etching techniques common to integrated circuit manufacturing. Several examples described herein relate to the generation of a photolithography mask used in a photolithography process for manufacturing a metalens.

[0007] The target design of a metalens may be created with respect to the desired optical function of the metalens. However, manufacturing variations can lead to deviations from the target design of the manufactured metalens. For example, the photolithography process used to manufacture the metalens may have a frequency band limited by the projection optical lens of the photolithography process. Depending on the bandwidth limiting aspect of the photolithography process, higher frequency light may be filtered out of the exposure pattern, for example, during the patterning of the photoresist. The absence of higher frequency light can result in corner rounding in the photoresist pattern, which is transferred to the metalens through etching. Corner rounding transferred to the metalens may be a deviation from the target design.

[0008] Deviations in the manufactured metalens from the target design can lead to a loss of optical efficiency. Different types of deviations from the target design can affect optical efficiency. One type of deviation from the target design that affects optical deviation is the regional deviation of the manufactured metaatoms within the metalens from the target design metaatoms. A high correlation has been observed between efficiency loss and regional deviation.

[0009] Accordingly, the technical advantages of this disclosure include, but are not limited to, reducing the optical efficiency loss of the fabricated metalens relative to the target design by taking into account the regional deviation. To address the technical problem of the optical efficiency loss of the fabricated metalens relative to the target design, several examples described herein take into account the regional deviation of the metaatoms to be fabricated in the metalens when generating the photolithography mask which will be used to fabricate the metaatoms. Various examples can be obtained to reduce the regional deviation of the fabricated metaatoms from the target design, and therefore to reduce the optical efficiency loss of the fabricated metalens relative to the target design. Other advantages or benefits can be obtained in various examples.

[0010] According to some examples, a metalens may be a permeable material layer on which a manufactured metaatom rests, or may include such a permeable material layer. For example, the permeable material may be a layer of silicon dioxide on a handle or support wafer (e.g., a silicon wafer) during manufacturing, or it may be a glass wafer (e.g., quartz, silicon dioxide, or another type of glass). The manufactured metaatoms in the examples may include silicon nitride (e.g., Si3N4), which may have any shape or pattern. The various examples described below generally illustrate metaatoms having rectangular regions for the sake of brevity and to avoid obscuring the various aspects of the examples. However, any shape may be used for metaatoms, whether regular, irregular, polygonal, or freeform.

[0011] Figure 1 shows a method 100 for manufacturing a metal lens, with some examples. Method 100 in Figure 1 is described in context with reference to the generalized environment in Figure 2.

[0012] In block 102, a target design 202 of the metalens (including the pattern of the target design metaatom 204) is obtained. The target design 202 may be a design of the metalens that does not take into account manufacturing variations in order to achieve the desired optical function. The target design 202 may include the desired shape and pattern of the target design metaatom 204. Inset 202a of the target design 202 in Figure 2 shows a portion of the target design 202, including the pattern of the target design metaatom 204. The local pattern of the target design metaatom 204 may vary throughout the design layout. The pattern of the target design metaatom 204 in Figure 2 may be, for example, for an achromatic metalens (as shown) or for another type of metalens.

[0013] Returning to Figure 1, in block 104, a mask design for the photolithography process is generated based on the regional deviation of the metaatoms to be manufactured for the metalens from the target design of the metalens. Various examples compensate for manufacturing or processing variations when generating the mask design. For example, as described above, the photolithography process may result in rounding of the corners of the exposed photoresist, and therefore rounding of the corners of that material (e.g., metaatoms) that have been etched to have a pattern of photoresist transferred to the material. Figures 3A, 3B, 4A, and 4B illustrate possible corner rounding. Figures 3A and 3B are perspective and layout views, respectively, of the target design metaatom 302. The target design metaatom 302 has a rectangular region in the layout view (e.g., the XY plane) that includes an acute angle, a 90-degree angle in this example. Figures 4A and 4B are perspective and layout views, respectively, of the manufactured metaatom 402. The fabricated metaatoms 402 are generally rectangular but have rounded corners. This rounding of the corners may result from the photolithography process that produced the fabricated metaatoms 402, which is used to etch and pattern the material. As will be described in further detail later, the generation of a mask design can reduce the regional misalignment between the target design metaatoms and the planned-to-produce metaatoms that will be fabricated (e.g., etched) using a photolithography process that uses a photolithography mask fabricated based on the mask design. In some examples, the generation of the mask design attempts to result in zero regional misalignment between the target design metaatoms and the planned-to-produce metaatoms (e.g., the region of the target design metaatoms is equal to the region of the planned-to-produce metaatoms).

[0014] Returning to Figure 1, in block 106, a photolithography mask 210 is manufactured based on the mask design. The photolithography mask 210 may be manufactured using any acceptable process. In block 108, a metalens 232 is manufactured, and the manufacture of the metalens 232 includes using the photolithography mask 210 in a photolithography process. For example, the photolithography mask 210 may be used in a photolithography process to pattern a photoresist 212, and the patterned photoresist 212 is used as a mask for etching the metaatomic material 214 into the manufactured metaatoms 234 of the metalens 232.

[0015] More specifically, the photolithography process may include generating light 220 from a light source 218 and transmitting the light 220 through a photolithography mask 210 to generate a pattern of light. The pattern of light is incident on a photoresist 212 to pattern the photoresist 212. Then, using the photoresist 212 as a mask during the etching process, the pattern of the photoresist 212 is transferred to the metaatomic material 214, thereby forming the fabricated metaatoms 234. The metalens 232 may further include a substrate 216 on which the metaatomic material 214, and thus the fabricated metaatoms 234, are disposed. Inset 232a of the metalens 232 shows a portion of the metalens 232, which includes a pattern of the fabricated metaatoms 234 corresponding to the target design metaatom 204 in inset 202a of the target design 202.

[0016] Figure 5 shows a first method 500 for generating a mask design in block 104 of Figure 1, with some examples. The first method 500 may be a rule-based correction for generating a mask design. In block 502, a lookup table (LUT) is created, at least partially, based on the regional considerations of the target design metaatom. The LUT is populated by various patterns of target design metaatoms that may be used in the target design of the metalens. The LUT is indexed based on the region of the target design metaatom, but may also be indexed based on the X, Y coordinates, and shape of the target design metaatom. Furthermore, the LUT may be indexed based on the dimensions of adjacent metaatoms. The mask dimensions are a function of the target dimensions, but may also be a function of adjacent patterns. For each indexed target design metaatom in the LUT, the LUT contains a corresponding mask pattern relating to the photolithography mask, thereby yielding a given intended-to-manufacture metaatom. For an indexed target-design metaatom, the corresponding planned-to-manufacture metaatom has a reduced regional shift, which may result in zero regional shift relative to the indexed target-design metaatom. The mask pattern for a given target-design metaatom may be determined through physical experiments and / or photolithography simulations, and the mask pattern for a given target-design metaatom used to populate the LUT is a mask pattern determined to appropriately reduce the regional shift between the given target-design metaatom and the planned-to-manufacture metaatom.

[0017] In block 504, mask patterns corresponding to target design metaatoms are obtained from the LUT. For example, for a given target design metaatom, the region of the target design metaatom, and if applicable, its dimensions, as well as the dimensions of adjacent metaatoms, are used to find the corresponding mask pattern (for example, by indexing it to the corresponding mask pattern). In block 506, a mask design is generated containing the obtained mask patterns. The mask patterns may be placed in locations in the mask design that correspond to each target design metaatom in the target design.

[0018] As described with respect to blocks 106 and 108 in Figure 1, a photolithography mask can be manufactured and used in the photolithography process using a mask design to form the fabricated metaatoms. Since a mask design is generated that includes a mask pattern selected from a LUT populated with mask patterns for reducing regional displacement, the regional displacement of the fabricated metaatoms of the fabricated metalens relative to the target design metaatoms of the target design can be reduced. This reduced regional displacement can result in reduced optical efficiency loss of the fabricated metalens.

[0019] Figure 6 shows a second method 600 for generating a mask design in block 104 of Figure 1, with some examples. The second method 600 may be a model-based optical proximity correction (OPC) using retargeting to generate the mask design. In block 602, an initial target design containing the target design meta-atom is obtained, as in block 102 of Figure 1. In block 604, an OPC with edge position error (EPE) is performed to obtain a mask design containing a first perturbation meta-atom. In the first iteration, the OPC with EPE may perturb (e.g., move) the edges of various target design meta-atoms to obtain a mask design containing the first perturbation meta-atom. In subsequent iterations, the OPC with EPE may further perturb the edges of a second perturbation meta-atom (described later) to obtain a mask design containing the first perturbation meta-atom. For convenience in this specification, the region of the first perturbed meta-atom in repeating N is A PERTURB,N (σB N-1 This is shown by ), where B0=0 when N=1. Furthermore, for convenience in this specification, the target bias determined in iteration N is B N This is shown, and the decay rate is denoted by σ. The target bias and decay rate are described thereafter. For brevity, the target bias entering the first iteration N=1 is initialized to zero (e.g., B0=0). Block 604 can implement any OPC with the EPE technique.

[0020] In block 606, based on a mask design including a first perturbation meta-atom, the fabrication of the planned meta-atom to be fabricated is simulated, and a simulated region of the planned meta-atom to be fabricated is determined. The simulation can use, for example, any lithography process simulation software. The simulation can simulate the lithography process using a simulated photolithography mask fabricated according to the mask design including the first perturbation meta-atom, and use the lithography process to form the simulated planned meta-atom to be fabricated (for example, pattern the photoresist to obtain a mask for etching the simulated planned meta-atom to be fabricated). Using the result of the simulation, the simulated region of the planned meta-atom to be fabricated can be determined. For convenience in this specification, the simulated region of the planned meta-atom in iteration N is A 2BFAB,N (A PERTURB,N (σB N-1 )) or simply, A 2BFAB,N is denoted by.

[0021] In block 608, a region deviation of the simulated region of the planned meta-atom from the target region of the target design meta-atom is determined. The region deviation is the difference between the simulated planned meta-atom to be fabricated and the target region of the corresponding target design meta-atom. As shown previously, the simulated region is generated by simulating the fabrication of the planned meta-atom to be fabricated, and that fabrication is based on the corresponding first perturbation meta-atom in the mask design. The region of the first perturbation meta-atom is a function of any perturbation of the edge in block 604 and, if present, any application of the target bias in the previous iteration (described subsequently). For convenience in this specification, the target region of the target design meta-atom is denoted by A TARGET . Thus, the region deviation ΔA N ; for a given planned meta-atom to be fabricated and the corresponding target design meta-atom in the Nth iteration can be generalized as follows in equation (1). ΔA N =A TARGET -A 2BFAB,N (APERTURB,N (σB N-1 )) Equation (1) The region shift can be determined in block 608 with respect to each planned-to-manufacture metaatom in the mask design and the corresponding target-design metaatom.

[0022] In block 610, a determination is made as to whether the region deviation is within the design specification range. For example, the design specification may be that there is no region deviation exceeding 10% of the region of the corresponding target design metaatom. The design specification may be further tightened to account for process drift during production, for example, up to 2%. If the determination result in block 610 is that the region deviation is within the design specification, the mask design is returned in block 612 as the planned manufacturing mask design (for example, in block 106 in Figure 1).

[0023] If the result in block 610 indicates that there are no domain deviations (e.g., any one or more domain deviations) within the design specifications, then in block 612, a target bias is determined based on the simulated domain of the planned-to-manufacture metaatom and the domain of the target-design metaatom. The target bias is the amount by which the dimensions of the first perturbed metaatom are further perturbed, thereby correcting the domain of the first perturbed metaatom. Generally, a target bias is determined that can reduce domain deviations in subsequent iterations. In the current iteration N, the domain deviation in subsequent iterations (N+1) is, for convenience,

[0024]

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[0026] Target bias B in iteration N N This is the target bias B from the previous iteration N-1. N-1 , and the gradually increasing target bias δB in iteration N N It is possible to accumulate (for example, B N =B N-1 +δB N ), or by another method, target bias B from the previous iteration N-1 N-1 , and the gradually increasing target bias δB in iteration N N This can be taken into consideration. By determining (and subsequently applying) the target bias, it is generally possible to maintain the schematic shape of the region of the target design metaatom in the region of the second perturbed metaatom (for example, maintaining shape fidelity).

[0027] Target bias B N This can be any number of target biases along each axis, or it can include. For example, in a target design area that is a square, target bias B N B N =B x,N =B y,N As such, it may be equal in both the x and y directions. In other examples, in a non-square rectangular region, the target bias B N B N ={B x,N ,B y,N}, B x,N ≠B y,NThus, the set may include a target bias in the x-direction and another target bias in the y-direction. Other shapes of the target design region may have different sets of target biases. For example, a free-form shape may have a number of target biases along any given axis. Equation (2) above can be solved analytically in some cases and numerically in other cases (such as for free-form shapes).

[0028] In block 616, a target bias is applied to the first perturbed metaatom to obtain a second perturbed metaatom. For example, one or more dimensions of the perturbed metaatom may be modified based on the corresponding target bias, such as by adding or subtracting the target bias to the dimensions. The target bias may be applied symmetrically around the center of each perturbed metaatom (e.g., by adding or subtracting). A damping rate σ may be applied to the target bias to improve the convergence of the correction iterations by reducing oscillating overcorrection. The damping rate may be, for example, 0.7 to 0.9 in the first iteration and can be reduced to approximately 0.5 in subsequent iterations. For convenience as used herein, the region of the second perturbed metaatom to which the target bias is applied in iteration N is A PERTURB,N (σB N This is shown by ).

[0029] Next, in block 604, in subsequent iterations, OPC with EPE is performed on a second perturbed metaatom containing a target bias to obtain a mask design containing the first perturbed metaatom. The loops of blocks 604, 606, 608, 610, 614, and 616 can be executed for any number of iterations, such as until the domain shift falls within the design specification range, as determined by block 610. For example, to avoid infinite looping, a loop counter and a condition for exiting the loop based on the loop counter, or other conditions, may be used.

[0030] As described with respect to blocks 106 and 108 in Figure 1, a photolithography mask can be manufactured and used in the photolithography process using the mask design to form the manufactured metaatoms. Since the mask design is generated based on biasing the target design metaatoms, the regional deviation of the manufactured metaatoms of the manufactured metalens relative to the target design metaatoms can be reduced. This reduced regional deviation can result in reduced optical efficiency loss of the manufactured metalens.

[0031] A simple example of some operations of the second method 600 in Figure 6 is described in relation to Figure 7. In this example, the shape of the region of the target design metaatom is square. For simplicity, it is assumed that no perturbation occurs in block 604. That is, for a given target design metaatom, in the first iteration N=1, the region of the first perturbed metaatom is equal to the region of the target design metaatom (as shown in equation (3)), and in subsequent iterations N>1, the region of the first perturbed metaatom is equal to the region of the second perturbed metaatom, which includes the target bias applied in the previous iteration (N-1) (as shown in equation (4)). In general, these assumptions lead to the following: For N=1, A PERTURB,1 (σB0=0)=A TARGET Equation (3)

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[0034] Figure 7 shows the target design metaatom (e.g., A) containing the center 704. TARGETThis shows region 702 of ). In this example, the shape of region 702 is square. In the first iteration N=1, based on the assumption of equation (3) above, region 706 of the first perturbed metaatom (following block 606) is equal to region 702 of the target design metaatom. The simulation based on region 706 of the first perturbed metaatom is equal to the simulated region 708 of the planned metaatom (e.g., A 2BFAB,1 (A PERTURB,1 This results in (σB0=0). The domain displacement ΔA1 is assumed to exceed the design specifications.

[0035] To determine the value of the target bias, the region of the planned metaatom is assumed to be approximately the region of the first perturbed metaatom in the next iteration. Therefore, in iteration N=1, the approximate value of the region of the planned metaatom in the next iteration N=2 is equal to the region of the first perturbed metaatom in the next iteration N=2 perturbed by the incremental target bias (for example,

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[0038] The second perturbation metaatom of iteration N=1 (for example, A PERTURB,1 To obtain (σB1), the target bias is applied to the first perturbed metaatom along with the decay rate. The application of the target bias and decay rate results in the region 710 of the second perturbed metaatom. The decayed target bias is applied symmetrically along a given axis, around the center 704. Thus, half of the decayed target bias 712a (for example)

[0039]

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[0040] In the second iteration N=2, based on the assumption of equation (4) above, the region 710 of the first perturbed metaatom (according to block 606) is equal to the region 710 of the second perturbed metaatom including the target bias applied in the previous iteration N=1 (for example, A PERTURB,2 (σB1) = A PERTURB,1 (σB1)). The simulation based on region 710 of the first perturbed metaatom is the simulated region 714 of the planned metaatom (for example, A 2BFAB,2(A PERTURB,2 This results in (σB1). The domain displacement ΔA2 is assumed to exceed the design specifications.

[0041] To determine the value of the target bias, the region of the planned metaatom is assumed to be approximately the region of the first perturbed metaatom in the next iteration. Therefore, in iteration N=2, the approximate value of the region of the planned metaatom in the next iteration N=3 is equal to the region of the first perturbed metaatom in the next iteration N=3 perturbed by the incremental target bias (for example).

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[0044] The second perturbing meta-atom (for example, A PERTURB,2 To obtain (σB2), the target bias, along with the decay rate, is applied to the first perturbed metaatom. The application of the target bias and decay rate results in the region 716 of the second perturbed metaatom. The decayed target bias is applied symmetrically around the center 704 along a given axis, as previously described.

[0045] In the third iteration N=3, based on the assumption of equation (4) above, the region 716 of the first perturbed metaatom (following block 606) is equal to the region 716 of the second perturbed metaatom containing the target bias applied in the previous iteration N=2 (for example, A PERTURB,3 (σB2) = A PERTURB,2 (σB2)). The simulation based on region 716 of the first perturbed metaatom is the simulated region 718 of the planned metaatom (for example, A 2BFAB,3 (A PERTURB,3 This results in (σB2). The region shift ΔA3 is assumed to be within the design specification range. Therefore, the region 716 of the first perturbed metaatom is returned to generate the design mask.

[0046] Figure 8 shows an exemplary machine of computer system 800, within which a set of instructions may be executed to cause the machine to perform any one or more of the procedures discussed herein. More specifically, computer system 800 may include stored instructions (e.g., stored on a non-temporary computer-readable medium) that, when executed by one or more processors of computer system 800, perform the procedures in whole or in part in blocks 102, 104 and / or methods 500, 600 in Figures 1, 5, and 6. In various examples, the machine may be connected to other machines (e.g., network connections) on a LAN, intranet, extranet, and / or the internet. The machine may operate as a server or client machine within the capabilities of a server or client machine in a client-server network environment, as a peer machine in a peer-to-peer (or distributed) network environment, or as a server or client machine in a cloud computing infrastructure or environment.

[0047] A machine can be a personal computer (PC), tablet PC, set-top box (STB), personal digital assistant (PDA), mobile phone, web device, server, network router, switch or bridge, or any machine capable of executing a set of instructions (sequential or otherwise) that define the actions taken by that machine. Furthermore, although a single machine is illustrated, the term “machine” should also be understood to include any set of machines that individually or together execute a set (or set) of instructions to perform any one or more of the procedures discussed herein.

[0048] An exemplary computer system 800 includes processing devices 802, main memory 804 (e.g., read-only memory (ROM), flash memory, synchronous DRAM (SDRAM), and other dynamic random access memory (DRAM)), static memory 806 (e.g., flash memory, static random access memory (SRAM), etc.), and data storage devices 818, all of which communicate with each other via a bus 830.

[0049] The processing device 802 represents one or more processors, such as a microprocessor or a central processing unit. More specifically, the processing device may be a complex instruction set computing (CISC) microprocessor, a reduced instruction set computing (RISC) microprocessor, a very long instruction word (VLIW) microprocessor, or a processor that implements other instruction sets, or a processor that implements a combination of instruction sets. The processing device 802 may further be one or more dedicated processing devices, such as an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), a digital signal processor (DSP), or a network processor. The processing device 802 may be configured to execute instructions 826 for performing the operations and steps described herein.

[0050] The computer system 800 may further include a network interface device 808 for communication over the network 820. The computer system 800 may further include a video display unit 810 (e.g., a liquid crystal display (LCD) or a cathode ray tube (CRT)), an alphanumeric input device 812 (e.g., a keyboard), a cursor control device 814 (e.g., a mouse), a graphics processing unit 822, a signal generation device 816 (e.g., a speaker), another graphics processing unit 822, a video processing unit 828, and an audio processing unit 832.

[0051] The data storage device 818 may include a machine-readable storage medium 824 (also known as a non-temporary computer-readable storage medium) on which one or more sets of instructions 826 or software that embody any one or more of the procedures or functions described herein are stored. The instructions 826 may further reside entirely or at least partially within the main memory 804 and / or processing device 802 while the instructions 826 are being executed by the computer system 800, and the main memory 804 and processing device 802 also constitute a machine-readable storage medium.

[0052] In some implementations, instruction 826 includes instructions for performing the functions corresponding to the Disclosure. Although the machine-readable storage medium 824 is shown as a single medium in exemplary implementations, the term “machine-readable storage medium” should be understood to include a single or multiple mediums (e.g., a centralized or distributed database, and / or associated caches and servers) that store one or more sets of instructions. The term “machine-readable storage medium” should further be understood to include any medium capable of storing or encoding a set of instructions for machine execution and causing a machine and processing device 802 to perform any one or more of the procedures of the Disclosure. Accordingly, the term “machine-readable storage medium” should be understood to include, but not be limited to, solid-state memory, optical media, and magnetic media.

[0053] Some parts of the detailed explanations presented above have been presented in the form of algorithms and symbolic representations of operations on data bits within computer memory. These algorithmic descriptions and representations are the way used by those skilled in the data processing art to most efficiently communicate the substance of the work of those skilled in the data processing art to others skilled in the art. An algorithm can be a set of operations that lead to a desired result. An operation is an operation that requires the skillful physical manipulation of a physical quantity. Such quantities can take the form of electrical or magnetic signals that can be stored, combined, compared and otherwise manipulated. Such signals may be referred to as bits, values, elements, symbols, codes, terms, or numbers, etc.

[0054] However, it should be noted that all these and similar terms should be associated with the appropriate physical quantities and are merely convenient labels applied to those quantities. Throughout this statement, unless otherwise stated as is evident from this disclosure, certain terms are understood to refer to actions and processes of a computer system or similar electronic computing device. A computer system or similar electronic computing device manipulates data represented as physical (electronic) quantities in the computer system's registers and memory, and converts it into other data similarly represented as physical quantities in the computer system's memory or registers or other such information storage devices.

[0055] This disclosure further relates to an apparatus for performing the operations described herein. This apparatus may be specifically constructed for a given purpose, or may include a computer that is selectively activated or reconfigured by a computer program stored within the computer. Such computer programs may be stored on non-temporary computer-readable storage media, such as any type of disk including floppy disks, optical disks, CD-ROMs, and magneto-optical disks, read-only memory (ROM), random access memory (RAM), EPROM, EEPROM, magnetic or optical cards, or any type of medium suitable for storing electronic instructions, each coupled to a computer system bus.

[0056] The algorithms and displays presented herein are not inherently related to any particular computer or other device. Various other systems may be used with the programs taught herein, or it may be more convenient to construct a more specialized device to perform the methods. Furthermore, this disclosure is not written in relation to any particular programming language. It will be understood that various programming languages ​​may be used to perform the teachings of this disclosure as described herein.

[0057] This disclosure may include a machine-readable storage medium on which instructions are stored, and may be provided as a computer program product or software that can be used to program a computer system (or other electronic device) to perform the processes described herein. A machine-readable storage medium includes any mechanism for storing information in a form readable by a machine (e.g., a computer). For example, machine-readable (e.g., computer-readable) storage mediums include machine-readable (e.g., computer-readable) storage mediums such as read-only memory (ROM), random-access memory (RAM), magnetic disk storage mediums, optical storage mediums, and flash memory devices.

[0058] One example is the method. A target design for a metalens is obtained. The target design includes target design metaatoms. Based on the regional shift of the metalens' planned metaatoms relative to the target design metaatoms, one or more processors generate a mask design.

[0059] Another example is a non-temporary computer-readable storage medium containing stored instructions. When executed by one or more processors, the instructions cause one or more processors to obtain a target design for the metalens and generate a mask design based on the region shift. The target design includes target design metaatoms. The region shift is the region shift of the metalens' planned manufacturing metaatoms relative to the target design metaatoms.

[0060] A further example is the method. A target design for a metalens is obtained. The target design includes a target design metaatom. The target design metaatom has a corresponding first planned-to-manufacture metaatom. A mask design is generated by one or more processors. The mask design includes a modified metaatom corresponding to the target design metaatom. The modified metaatom has a corresponding second planned-to-manufacture metaatom. For each modified metaatom, the region shift between the region of the corresponding target design metaatom and the region of the corresponding second planned-to-manufacture metaatom is smaller than the region shift between the region of the corresponding target design metaatom and the region of the corresponding first planned-to-manufacture metaatom.

[0061] The aforementioned disclosures describe the implementations of this disclosure with reference to specific exemplary implementations. It will be apparent that various modifications can be made to the implementations of this disclosure without departing from the broader intent and scope of the implementations of this disclosure as specified in the following claims. Where this disclosure refers to several elements in the singular, two or more elements may be depicted in the drawings, and similar elements will be labeled with similar numbers. Therefore, this disclosure and the drawings should be considered in an illustrative rather than restrictive sense.

Claims

1. A step of obtaining a target design for a metalens, wherein the target design includes a target design metaatom. A method comprising the step of generating a mask design by one or more processors based on the regional shift of the metaatoms to be manufactured for the metalens relative to the target design metaatoms.

2. A step of manufacturing a photolithography mask based on the mask design, The method according to claim 1, further comprising the step of manufacturing the metalens, which includes using the photolithography mask in a photolithography process.

3. The step of generating the mask design is, A step of obtaining a lookup table containing mask patterns, wherein each mask pattern in the lookup table is indexed at least partially based on the region of the corresponding target design metaatom. For each of the aforementioned target design metaatoms, the step of obtaining a mask pattern from the lookup table corresponding to the region of each of the aforementioned target design metaatoms, The method according to claim 1, further comprising the step of generating the mask design including the acquired mask pattern.

4. The step of generating the mask design is, The steps include performing optical proximity correction along with edge position error technique based on the target design in order to obtain a provisional mask design including a first perturbed metaatom, The steps include: simulating the planned metaatoms based on the aforementioned provisional mask design; The steps include determining the region deviation of the simulated planned-to-manufacture metaatom from the target-design metaatom, When the aforementioned area deviation is within the design specification range, the step is to assign the provisional mask design as the mask design, When the aforementioned region deviation is not within the design specification range, For each of the region deviations that are outside the design specification range, the step of determining a target bias based on the region of the corresponding simulated planned-to-manufacture metaatom and the region of the corresponding target-design metaatom, The method according to claim 1, comprising the step of applying the respective target bias to the corresponding first perturbation metaatom in the provisional mask design for each determined target bias in order to obtain the corresponding second perturbation metaatom in the provisional mask design.

5. The method according to claim 4, wherein the target bias is determined based on the difference between an approximation of the region of the corresponding target design metaatom and the region of the planned-to-manufacture metaatom to be simulated, the region of the planned-to-manufacture metaatom to be simulated is based on the corresponding simulated planned-to-manufacture metaatom, and the incremental region change of the corresponding first perturbation metaatom is based on an incremental target bias.

6. The method according to claim 4, wherein the step of applying each of the target biases further includes the step of applying a decay rate together with the respective target biases to the corresponding first perturbation metaatom in the provisional mask design in order to obtain the corresponding second perturbation metaatom in the provisional mask design.

7. The step of generating the mask design is, Iterate until the domain deviation falls within the design specification range. A step of performing optical proximity correction along with edge position error technique based on a design in order to obtain a provisional mask design including a first perturbed metaatom, wherein the design is the target design in the first iteration and the provisional mask design from the preceding iteration in subsequent iterations. The steps include: simulating the planned metaatoms based on the aforementioned provisional mask design; The steps include determining the region deviation of the simulated planned-to-manufacture metaatom from the target-designed metaatom, For each of the region deviations that are outside the design specification range, the step of determining a target bias based on the region of the corresponding simulated planned-to-manufacture metaatom and the region of the corresponding target-design metaatom, The process includes the step of applying the respective target bias to the corresponding first perturbation metaatom in the provisional mask design for each determined target bias in order to obtain the corresponding second perturbation metaatom in the provisional mask design, The method according to claim 1, wherein the step of generating the mask design further includes the step of assigning the provisional mask design as the mask design.

8. The method according to claim 7, wherein the target bias is determined based on the difference between an approximation of the region of the corresponding target design metaatom and the region of the planned-to-manufacture metaatom to be simulated, the region of the planned-to-manufacture metaatom to be simulated is based on the corresponding simulated planned-to-manufacture metaatom, and the incremental region change of the corresponding first perturbation metaatom is based on an incremental target bias.

9. The method according to claim 7, wherein the step of applying each of the target biases further includes the step of applying a decay rate together with the respective target biases to the corresponding first perturbation metaatom in the provisional mask design in order to obtain the corresponding second perturbation metaatom in the provisional mask design.

10. A non-temporary computer-readable storage medium containing stored instructions, wherein when the stored instructions are executed by one or more processors, the one or more processors To obtain a target design for a metalens, wherein the target design includes a target design metaatom. A non-temporary computer-readable storage medium that generates a mask design based on the regional shift of the metaatoms to be manufactured for the metalens relative to the target design metaatoms.

11. When executed by the one or more processors, the instruction causes the one or more processors to generate the mask design. When the instruction is further executed by the one or more processors, the one or more processors Obtaining a lookup table containing mask patterns, wherein each mask pattern in the lookup table is indexed at least partially based on the region of the corresponding target design metaatom. For each of the aforementioned target design metaatoms, a mask pattern is obtained from the lookup table corresponding to the region of each of the aforementioned target design metaatoms. A non-temporary computer-readable storage medium according to claim 10, comprising an instruction to generate the mask design including the acquired mask pattern.

12. When executed by the one or more processors, the instruction causes the one or more processors to generate the mask design. When the instruction is further executed by the one or more processors, the one or more processors In order to obtain a provisional mask design including the first perturbed metaatom, optical proximity correction is performed based on the target design, along with edge position error technique. The planned metaatoms to be manufactured are simulated based on the aforementioned provisional mask design, To determine the regional deviation of the simulated planned-to-manufacture metaatom from the target-design metaatom, When the aforementioned area deviation is within the design specification range, the provisional mask design is assigned as the mask design, When the aforementioned region deviation is not within the design specification range, For each of the region deviations that fall outside the design specification range, a target bias is determined based on the region of the corresponding simulated planned-to-manufacture metaatom and the region of the corresponding target-design metaatom. A non-temporary computer-readable storage medium according to claim 10, comprising instructions to cause the system to apply the respective target bias to the corresponding first perturbation metaatom in the provisional mask design for each determined target bias in order to obtain the corresponding second perturbation metaatom in the provisional mask design.

13. The non-temporary computer-readable storage medium according to claim 12, wherein the target bias is determined based on the difference between an approximation of the region of the corresponding target design metaatom and the region of the planned-to-manufacture metaatom to be simulated, the region of the planned-to-manufacture metaatom to be simulated is based on the corresponding simulated planned-to-manufacture metaatom, and the incremental region change of the corresponding first perturbation metaatom is based on an incremental target bias.

14. When executed by the one or more processors, the instruction causes the one or more processors to generate the mask design. When the instruction is further executed by the one or more processors, the one or more processors Iterate until the domain deviation falls within the design specification range. To obtain a provisional mask design containing a first perturbed metaatom, the optical proximity correction is performed based on the design, along with an edge position error technique, wherein the design is the target design in the first iteration and the provisional mask design from the preceding iteration in subsequent iterations. The planned metaatoms to be manufactured are simulated based on the aforementioned provisional mask design, To determine the region deviation of the simulated planned-to-manufacture metaatom from the target-designed metaatom, For each of the region deviations that fall outside the design specification range, a target bias is determined based on the region of the corresponding simulated planned-to-manufacture metaatom and the region of the corresponding target-design metaatom. In order to obtain the corresponding second perturbation metaatom in the provisional mask design, the process involves applying the respective target bias to the corresponding first perturbation metaatom in the provisional mask design for each determined target bias, and when this is performed by one or more processors, the process further involves one or more processors A non-temporary computer-readable storage medium according to claim 10, including an instruction to assign the provisional mask design as the mask design.

15. The non-temporary computer-readable storage medium according to claim 14, wherein the target bias is determined based on the difference between an approximation of the region of the corresponding target design metaatom and the region of the planned-to-manufacture metaatom to be simulated, the region of the planned-to-manufacture metaatom to be simulated is based on the corresponding simulated planned-to-manufacture metaatom, and the incremental region change of the corresponding first perturbation metaatom is based on an incremental target bias.

16. A step of obtaining a target design for a metalens, wherein the target design includes a target design metaatom, and the target design metaatom has a corresponding first planned-to-manufacture metaatom. A method comprising the steps of generating a mask design by one or more processors, which includes a modified metaatom corresponding to the target design metaatom, wherein the modified metaatom has a corresponding second planned-to-manufacture metaatom, and for each modified metaatom of the modified metaatom, the region shift between the region of the corresponding target design metaatom and the region of the corresponding second planned-to-manufacture metaatom is smaller than the region shift between the region of the corresponding target design metaatom and the region of the corresponding first planned-to-manufacture metaatom.

17. The method according to claim 16, wherein the step of generating the mask design is rule-based based on the region of the target design metaatom.

18. The method according to claim 16, wherein the step of generating the mask design uses a lookup table (LUT) containing available modified metaatoms indexed based on each region of the target design metaatom.

19. The method according to claim 16, wherein the step of generating the mask design is model-based, based on the regional deviation between each approximate value of the region of the target design metaatom and the region of the simulated planned-to-manufacture metaatom.

20. The step of generating the mask design is performed for each modified metaatom of the modified metaatoms, The steps include determining a target bias based on approximate values ​​of the regions of the corresponding target design metaatoms and the regions of the planned-to-manufacture metaatoms obtained from each of the modified metaatoms, The method according to claim 16, comprising the step of applying the target bias to the region of the corresponding target design metaatom, wherein the target bias applied to the region of the corresponding target design metaatom obtains at least partially the respective modified metaatom.

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