Method for improving productivity of photoetching equipment

Abstract

The invention discloses a method for improving the productivity of photoetching equipment. The method comprises the following steps: acquiring priorities, quantity information and process information of all products on a current station line of a previous process; according to the priorities of all the products, a scoring rule is formulated; according to the scoring rule and the process information, respectively calculating the sum of points of the same photomask products in all the products; the previous procedure performs batch dispatching on all the products according to the integral sum to obtain a dispatching sequence of all the products; and sorting the photomasks required to be used by the photoetching site according to the dispatching sequence. According to the method, the specific sequence of switching of the photomasks in the photoetching area can be quickly mastered, misoperation possibly occurring when online personnel inquire and judge product types can be reduced, meanwhile, the production efficiency of a machine table is improved, and the production cycle of product operation is shortened.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor manufacturing, and particularly relates to a method for improving the production capacity of lithography equipment. Background Art

[0002] In the semiconductor industry, lithography is a key process in chip production and manufacturing. The most core equipment in the process is the lithography machine, and its resolution determines the minimum line width of semiconductor circuits. With the continuous evolution of semiconductor advanced process nodes, the production efficiency of lithography machines plays an important role in product manufacturing. Therefore, improving the production capacity of lithography machines has become one of the urgent problems to be solved in the semiconductor industry.

[0003] The lithography machine is the most complex and expensive equipment in chip manufacturing. It contains multiple working units inside, and the link combination of the working units together determines the production cycle of wafers in the lithography process. Moreover, the parameter settings of the process directly affect the production capacity evaluation of the lithography machine. Inside the lithography machine, the processing of wafers is basically completed by three major steps: coating, exposure, and development. Among them, the frequent replacement of photomasks in the exposure step will increase the time cost of wafer production. The fundamental reason is that the dispatching order of the previous process is random, resulting in products with the same photomask not being able to enter the lithography process site in batches.

[0004] Regarding the hot issue of frequent photomask switching, the conventional practice of the existing technology in the industry is to optimize the dispatching logic of the products at the current station in the lithography area, and adopt the same-photomask dispatching method to reduce the number of photomask switches. The specific practice of the existing technology is to query the MES system to master the status of the current photomask, and after manual transportation, place the photomask to be used into the machine tool for exposure processing of the wafer. If the processing levels of the wafers are different, engineers need to manually search for and replace the photomasks. In simple cases, the photomasks can be directly transferred between machine tools, while when the photomask is in the photomask chamber or warehouse, a series of operations to find and move the photomask will delay the production process of the product. If the process progress before and after is not fully considered when replacing the photomask, it will also cause process delays for a large number of products and reduce the output efficiency of the lithography machine.

[0005] There are some problems with the method of only optimizing the products at the current station in the lithography area in the existing technology: If the arrival times of different batches of products with the same photomask at the lithography machine tool are too far apart, it will cause the products waiting for operation at the current station to wait for subsequent products with the same photomask for a long time, which will greatly increase the time cost and seriously affect the production efficiency of the lithography machine tool. Summary of the Invention

[0006] The purpose of the present invention is to provide a method for improving the production capacity of lithography equipment, aiming to solve the problem in the existing technology that only dispatching the products at the current station in the lithography area results in too large a difference in the arrival times of products with the same photomask at the lithography machine tool, too long waiting time for the products to be processed by the lithography equipment, and affecting the production efficiency of the lithography machine tool.

[0007] To achieve the above object, the present invention is realized through the following technical solutions:

[0008] The present invention provides a method for improving the production capacity of a lithography device, including:

[0009] Obtaining the priority, quantity information, and process information of all products on the current station line of the previous process;

[0010] Formulating a scoring rule according to the priority of all the products;

[0011] Calculating the total score of products with the same photomask among all the products respectively according to the scoring rule and the process information;

[0012] The previous process batches and assigns all the products according to the total score to obtain the dispatching order of all the products;

[0013] Sorting the photomasks required for the lithography station according to the dispatching order.

[0014] Preferably, the process information includes the product level information of all products on the current station line of the previous process, and the product level information corresponds one-to-one with the photomask information.

[0015] Preferably, the scoring rule includes:

[0016] Dividing the priority of all the products into several product grades, and each product grade corresponds to a product weight coefficient.

[0017] Preferably, the higher the product grade, the greater the corresponding product weight coefficient.

[0018] Preferably, according to the quantity information and the product level information, determine the quantity of products in each product grade corresponding to each type of photomask required to be used.

[0019] Preferably, calculate the total score of products with the same photomask according to the product quantity, the product weight coefficient, and the total product quantity in the quantity information.

[0020] Preferably, the total score G is calculated using the following formula:

[0021] G = (N1*H1 + N2*H2 + N3*H3…Nm*HT) / S

[0022] In the formula, N1, N2, N3…Nm respectively represent the product weight coefficients, N1 > N2 > N3 >…> Nm;

[0023] T represents the Tth grade, and the product grades include, from high to low in sequence: the 1st grade, the 2nd grade, the 3rd grade…the Tth grade;

[0024] H1, H2, H3…HT respectively represent the quantities of products of the same photomask when the product grades are the 1st grade, the 2nd grade, the 3rd grade…the Tth grade;

[0025] S represents the total quantity of products.

[0026] Preferably, the step of grouping and dispatching all the products according to the total integral sum to obtain the dispatching order of all the products in the front-end process includes: there are multiple total integral sums, arranging the multiple total integral sums in ascending or descending order to obtain an arrangement order, and sorting each type of product of the same photomask among all the products according to the arrangement order; the larger the total integral sum, the more preferential the shipping order of the corresponding product of the same photomask.

[0027] Preferably, the step of sorting the photomasks required for the lithography station according to the dispatching order includes: there are multiple types of photomasks required for the lithography station, and each type of photomask corresponds to one level of products in the front-end process, that is, each type of photomask corresponds to one total integral sum. Arranging the multiple total integral sums in ascending or descending order to obtain an arrangement order of products, and sorting all types of the photomasks according to the arrangement order of products; the larger the total integral sum, the more preferential the shipping order of the corresponding photomask.

[0028] Preferably, sorting the photomasks required for the lithography station according to the dispatching order to obtain the sorting of the photomasks, and verifying the grouping rate of the on-line products at the lithography station according to the sorting of the photomasks. The higher the grouping rate, the higher the production efficiency of the corresponding lithography equipment.

[0029] Preferably, according to the sorting of the photomasks, the number of photomask switches n is obtained, and the grouping rate λ is calculated by the following formula:

[0030] λ = S / n

[0031] In the formula, S represents the total quantity of products.

[0032] Compared with the prior art, the present invention has the following beneficial effects:

[0033] The present invention provides a method for improving the production capacity of a lithography device. By optimizing the lot dispatching method of the previous process, the production efficiency of the lithography device is improved. The lot grouping method of the previous process is improved and combined with the lot grouping means of the current lithography layer, so as to shorten the interval time for products of the same reticle batch to reach the lithography station. Furthermore, lot dispatching for products of the same reticle is realized to reduce the number of reticle switches. The present invention can not only quickly master the specific sequence of reticle switches in the lithography area, but also reduce the misoperations that may occur when on-line personnel query and judge the product type. At the same time, the production efficiency of the machine tool is improved and the production cycle of product operation is shortened. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the technical solutions of the present invention, the drawings required for description will be briefly introduced below. Obviously, the drawings in the following description are an embodiment of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts:

[0035] Figure 1 It is a schematic diagram of the dispatching result of the dispatching method in the production of the prior art lithography device;

[0036] Figure 2 It is a flowchart of the method for improving the production capacity of a lithography device provided by an embodiment of the present invention;

[0037] Figure 3 It is a schematic diagram of the dispatching result of the dispatching method provided by an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0038] The following further details the method for improving the production capacity of a lithography device proposed by the present invention in conjunction with the attached Figures 1 - 3 drawings and specific embodiments. According to the following description, the advantages and features of the present invention will be clearer. It should be noted that the drawings are in a very simplified form and all use non-precise scales, only for the purpose of conveniently and clearly assisting in explaining the embodiments of the present invention. In order to make the purpose, features and advantages of the present invention more obvious and understandable, please refer to the drawings. It should be noted that the structures, ratios, sizes, etc. shown in the drawings of this specification are only used to cooperate with the content disclosed in the specification for those who are familiar with this technology to understand and read, and are not used to limit the limiting conditions of the implementation of the present invention. Therefore, they do not have technical essence. Any modification of the structure, change of the ratio relationship or adjustment of the size should still fall within the scope covered by the technical content disclosed in the present invention without affecting the effects that the present invention can produce and the purposes that can be achieved.

[0039] In view of the problem that in the prior art, only the products at the current station in the lithography area are dispatched, resulting in a large difference in the arrival time of products with the same photomask at the lithography machine stage, a long waiting time for the lithography equipment to perform operations, and an impact on the production efficiency of the lithography machine stage, this embodiment provides a method for improving the production capacity of the lithography equipment.

[0040] The following is a detailed description of the method for improving the production capacity of the lithography equipment provided in this embodiment through specific embodiments and in combination with the attached Figure 2 and the attached Figure 3 ,. Refer to Figure 2 As shown, the specific steps of the method include:

[0041] Step S1: Obtain the priority, quantity information, and process information of all products on the current station line of the previous process; the process information includes the product level information of all products on the current station line of the previous process, and the product level information corresponds one-to-one with the photomask information. Products at the same level refer to products in the same layer in lithography production, and products in the same layer use the same photomask.

[0042] In this embodiment, the previous process refers to the production sites in other areas in front of the lithography main machine stage, that is, the previous process is the non-lithography area, and the current lithography station is the lithography area.

[0043] Step S2: According to the priorities of all the products, formulate a scoring rule; the scoring rule includes: dividing the priorities of all the products into several product levels, and each product level corresponds to a product weight coefficient. The higher the product level, the greater the corresponding product weight coefficient.

[0044] Step S3: Integral calculation. According to the scoring rule and the process information, calculate the total integral of the products with the same photomask among all the products respectively; according to the quantity information and the product level information, determine the quantity of products at each product level corresponding to each type of photomask required to be used. According to the product quantity, the product weight coefficient, and the total product quantity in the quantity information, calculate the total integral of the products with the same photomask. The total integral G is calculated using the following formula:

[0045] G = (N1*H1 + N2*H2 + N3*H3…Nm*HT) / S (1)

[0046] In the formula, N1, N2, N3…Nm respectively represent the product weight coefficients, N1 > N2 > N3 >…> Nm, where m is a positive integer; T represents the Tth level, and the product levels include, from high to low: the 1st level, the 2nd level, the 3rd level…the Tth level, where T is a positive integer; H1, H2, H3…HT respectively represent the product quantities of the products with the same photomask when the product levels are the 1st level, the 2nd level, the 3rd level…the Tth level; S represents the total product quantity.

[0047] The following takes an actual application as an example. In this example, the products are classified into first, second, third, and other grades, and the corresponding weights of products in different grades are: N1, N2, N3, N4 (where N1 > N2 > N3 > N4). There are three types of photomasks used in the lithography process in the example, namely: photomask A, photomask B, and photomask C. The quantities of products in the first, second, third, and other grades in the products of the previous process at the current station corresponding to photomask A are: K1, K2, K3, K4; the quantities of products in the first, second, third, and other grades in the products of the previous process at the current station corresponding to photomask B are: L1, L2, L3, L4; the quantities of products in the first, second, third, and other grades in the products of the previous process at the current station corresponding to photomask B are: M1, M2, M3, M4. The total quantity of all products on the line of the previous process at the current station is S.

[0048] Calculate the total score of products at each level in the previous process according to the scoring rules, and classify and sort the products of different photomasks based on the score of each level of products; products with a larger score value are given priority for shipping.

[0049] From the above formula (1), it can be obtained that the total score of all products using photomask A in the products on the line of the previous process at the current station is: (N1 * K1 + N2 * K2 + N3 * K3 + N4 * K4) / S.

[0050] The total score of all products using photomask B in the products on the line of the previous process at the current station is: (N1 * L1 + N2 * L2 + N3 * L3 + N4 * L4) / S.

[0051] The total score of all products using photomask C in the products on the line of the previous process at the current station is: (N1 * M1 + N2 * M2 + N3 * M3 + N4 * M4) / S.

[0052] According to the above calculations, the specific calculations of the total scores of the three photomasks are shown in Table 1 below:

[0053]

[0054] Table 1

[0055] Step S4: Batch grouping and dispatching. The previous process performs batch grouping and dispatching on all the products according to the total score to obtain the dispatching order of all the products; the specific steps include: there are multiple total scores, arranging the multiple total scores in ascending or descending order to obtain an arrangement order, and sorting each product of the same photomask among all the products according to the arrangement order; the larger the total score, the more preferential the shipping order of the corresponding product of the same photomask.

[0056] According to the above calculations, the total points of products at different levels are obtained. In the previous process, the LOT (LOT refers to the product) with a higher total reticle points will be preferentially grouped and dispatched, so as to reduce the time interval for the LOTs with the same reticle to reach the lithography production machine, increase the grouping rate of the products on the lithography line, and the calculation formula of the grouping rate refers to the calculation formula in the following formula (2).

[0057] In this embodiment, the essence of the grouping and dispatching in the previous process is to make more batches of LOTs with the same reticle appear at the lithography station in the same time, and reduce the number of reticle replacements at the lithography station.

[0058] Step S5: Reticle sorting, sort the reticles required by the lithography station according to the dispatching order. The reticle sorting is based on the preferential grouping and dispatching mode of LOTs with the same reticle in the previous layer (i.e., the previous process mentioned above), so that the LOTs on the line enter the lithography station in batches, and the integral calculation is the basis for grouping and dispatching in the previous process. Therefore, the steps of grouping and dispatching are integral calculation, grouping and dispatching, and reticle sorting. Sort the reticles required by the lithography station according to the dispatching order, and its specific steps include: The types of reticles required by the lithography station include multiple types, and each type of reticle corresponds to a level of product in the previous process, that is, each type of reticle corresponds to a total integral. Arrange the multiple total integrals in ascending or descending order to obtain the arrangement order of the products, and sort all types of the reticles according to the arrangement order of the products; The larger the total integral, the more preferential the dispatching order of the corresponding reticle.

[0059] Sort the reticles required by the lithography station according to the dispatching order to obtain the reticle sorting. According to the reticle sorting, verify the grouping rate of the products on the lithography line. According to the reticle sorting, obtain the number of reticle switches n, and the grouping rate λ is calculated by the following formula:

[0060] λ = S / n (2)

[0061] In the formula, S represents the total amount of products.

[0062] In the production of lithography equipment, the higher the grouping rate, the higher the production efficiency of the corresponding lithography equipment.

[0063] Compare Appendix Figure 1 and Appendix Figure 3 It can be seen that taking the setting of three reticles: reticle A, reticle B, and reticle C as an example, the prior art and this embodiment adopt different methods for the dispatching results of dispatching. As shown in Appendix Figure 3It can be seen that according to the above batch grouping and dispatching method, the same reticle LOTs grouped preferentially enter the lithography station in batches in the previous process, and then are uniformly dispatched at the lithography station. This not only realizes the continuous batch operation of products with the same reticle within the same time period, reduces the number of reticle replacements, and increases the batch grouping rate, but also can improve the working efficiency of the main machine tool to increase the production capacity of the lithography machine.

[0064] In summary, the above embodiments propose a method for improving the production efficiency of lithography equipment by optimizing the batch grouping and dispatching method of the previous process. Refer to Figure 3 the schematic diagram of the dispatching result of the dispatching method provided by the shown embodiment, which is different from the logic of the conventional dispatching in the prior art (refer to Figure 1 shown). By improving the previous layer batch grouping method and combining it with the current layer batch grouping means, the interval time for products with the same reticle to reach the lithography station is shortened, and then batch grouping and dispatching of products with the same reticle are realized to reduce the number of reticle switches. This method can not only quickly master the specific sequence of reticle switching in the lithography area, but also reduce the misoperations that may occur when on-line personnel query and judge the product type. At the same time, it improves the production efficiency of the machine tool and shortens the production cycle of product operation. The present embodiment proposes a new reticle batch grouping and dispatching method, that is, the batch grouping and dispatching method of the previous process, which reduces the number of reticle switches when processing products with different reticles at the current lithography station through pre-batch grouping of the previous layer, and the goods discharging method becomes more orderly, providing great reference value for the production capacity improvement of lithography machines in the industry.

[0065] It should be noted that in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "including a..." does not exclude the existence of additional identical elements in the process, method, article or device including the said element.

[0066] It should be noted that the devices and methods disclosed in the embodiments of this article can also be implemented in other ways. The device embodiments described above are merely illustrative. For example, the flowcharts and block diagrams in the accompanying drawings show the possible architectures, functions, and operations of devices, methods, and computer program products according to multiple embodiments of this article. In this regard, each block in the flowchart or block diagram may represent a module, program, or part of code, and the part of the module, program segment, or code contains one or more executable instructions for implementing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the blocks may occur in a different order than that marked in the accompanying drawings. For example, two consecutive blocks can actually be executed substantially in parallel, and they can sometimes be executed in the reverse order, depending on the functions involved. It should also be noted that each block in the block diagram and / or flowchart, as well as the combination of blocks in the block diagram and / or flowchart, can be implemented by a dedicated hardware-based system for performing the specified functions or actions, or can be implemented by a combination of dedicated hardware and computer instructions.

[0067] In addition, each functional module in the various embodiments of this article can be integrated together to form an independent part, or each module can exist alone, or two or more modules can be integrated to form an independent part.

[0068] Although the content of the present invention has been introduced in detail through the above preferred embodiments, it should be recognized that the above description should not be considered as a limitation of the present invention. After those skilled in the art have read the above content, various modifications and alternatives to the present invention will be obvious. Therefore, the protection scope of the present invention should be defined by the appended claims.

Claims

1. A method for improving the production capacity of a lithography device, characterized in that, The method includes: Obtaining the priority, quantity information, and process information of all products on the current station line of the previous process; Formulating a scoring rule according to the priorities of all the products; Calculating the total score of products with the same photomask among all the products respectively according to the scoring rule and the process information; The previous process batches and assigns all the products according to the total score to obtain the dispatching order of all the products; Sorting the photomasks required for the lithography station according to the dispatching order.

2. The method for improving the production capacity of a lithography device according to claim 1, characterized in that, The process information includes the product level information of all products on the current station line of the previous process, and the product level information corresponds to the photomask information one by one.

3. The method for improving the production capacity of a lithography device according to claim 2, characterized in that, The scoring rule includes: Dividing the priorities of all the products into several product grades, and each product grade corresponds to a product weight coefficient.

4. The method for improving the production capacity of a lithography device according to claim 3, characterized in that, The higher the product grade, the greater the corresponding product weight coefficient.

5. The method for improving the production capacity of a lithography device according to claim 4, characterized in that, According to the quantity information and the product level information, determining the quantity of products of each product grade in the products corresponding to each type of photomask required to be used.

6. The method for improving the production capacity of a lithography device according to claim 5, characterized in that, Calculating the total score of products with the same photomask according to the product quantity, the product weight coefficient, and the total product quantity in the quantity information.

7. The method for improving the production capacity of a lithography device according to claim 6, characterized in that, The total score G is calculated using the following formula: G = (N1 * H1 + N2 * H2 + N3 * H3 … Nm * HT) / S In the formula, N1, N2, N3 … Nm respectively represent the product weight coefficients, and N1 > N2 > N3 > … > Nm; T represents the Tth grade, and the product grades include, from high to low in sequence: the 1st grade, the 2nd grade, the 3rd grade … the Tth grade; H1, H2, H3 … HT respectively represent the product quantities of products with the same photomask when the product grades are the 1st grade, the 2nd grade, the 3rd grade … the Tth grade; S represents the total product quantity.

8. The method for improving the production capacity of a lithography device according to claim 1, characterized in that, The step of the previous process batch-assigning and dispatching all the products according to the total score to obtain the dispatching order of all the products includes: there are multiple total scores, arranging the multiple total scores in ascending or descending order to obtain an arrangement order, and sorting each type of product with the same photomask among all the products according to the arrangement order; the greater the total score, the more preferential the discharging order of the product with the same photomask corresponding to it.

9. The method for improving the production capacity of a lithography device according to claim 1, characterized in that, The step of sorting the photomasks required for the lithography station according to the dispatching order includes: there are multiple types of photomasks required for the lithography station, and each type of photomask corresponds to a level of products in the previous process, that is, each type of photomask corresponds to a total score. Arranging the multiple total scores in ascending or descending order to obtain an arrangement order of products, and sorting all types of the photomasks according to the arrangement order of the products; the greater the total score, the more preferential the discharging order of the photomask corresponding to it.

10. The method for improving the production capacity of a lithography device according to claim 9, characterized in that, Sorting the photomasks required for the lithography station according to the dispatching order to obtain the sorting of the photomasks. According to the sorting of the photomasks, verifying the batch rate of the products on the lithography station line. The higher the batch rate, the higher the production efficiency of the corresponding lithography equipment.

11. The method for improving the production capacity of a lithography device according to claim 10, characterized in that, According to the sorting of the photomasks, the number of photomask switches n is obtained, and the lot grouping rate λ is calculated using the following formula: λ = S / n where S represents the total quantity of products.

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