A method for controlling non-product wafers in semiconductor process

Abstract

The present invention relates to the field of semiconductor manufacturing technology, and discloses a method for controlling non-product wafers in a semiconductor process. Non-product wafers are put into a non-product wafer type identification module and the type of non-product wafer put in is determined. The types of non-product wafers include control wafer source wafers, control wafers, furnace tube control wafers, warm-up wafers, and baffle wafers. The corresponding process flow is processed according to the acquired non-product wafer types. The control wafer source wafer is preprocessed, the control wafer is automatically or manually put into operation, the furnace tube control wafer is bound, the warm-up wafer is debugged, and the baffle wafer is filled. The present invention is used for an efficient and accurate control method for non-product wafers in a semiconductor manufacturing process, and for automatically intervening in the control of the production process with non-product wafers, and strictly controlling the interference of non-product wafers with product wafers in the process production process to improve the yield and production efficiency.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor manufacturing technology, and specifically, to a method for controlling non-product wafers in a semiconductor process, which is used for an efficient and accurate method for controlling non-product wafers in a semiconductor manufacturing process and for automatically intervening in a production process with non-product wafers, thereby strictly controlling the interference of non-product wafers with product wafers in the process production process to improve yield and production efficiency. Background Art

[0002] In the process of semiconductor chip manufacturing, the process from silicon wafer to final product is an extremely complex process, which involves hundreds of complex processes such as oxidation, lithography, etching, doping, thin film deposition, metallization, etc. At present, semiconductor chip manufacturing is becoming more and more sophisticated, complex, and customized. The Manufacturing Execution System (MES) has become an indispensable management tool for semiconductor production. Its function can control the entire process of semiconductor production and manufacturing, optimize the production process, ensure reliable product performance, and meet user customization needs. The types of products managed in the MES system include production lots that actually need to be delivered and non-product lots (NPW); the main function of non-product lots is to ensure the stability of the process of manufacturing product lots, accurate equipment parameters, and improve production efficiency and yield. The focus of management in the existing MES system is mostly product lots, and the control of non-product lots is relatively chaotic. Some types of non-product lots even have no clear control in the system, and rely entirely on manual control and recording by operators. Since the process involves a lot of measurement stations, measuring every batch of products will lead to low production efficiency and increased pressure on the production line. Imprecise process control can easily lead to unnecessary scrap and rework, bringing additional wafer manufacturing costs to the factory.

[0003] Therefore, in order to solve the above problems, the present invention adopts a highly efficient and accurate control method for non-product wafers in the semiconductor manufacturing process and automatically intervenes in the production process of non-product wafers to strictly control the intervention of non-product wafers in the process production process to improve the yield and production efficiency. Summary of the invention

[0004] The purpose of the present invention is to provide a method for controlling non-product wafers based on semiconductor process flow, through an efficient and accurate control method for non-product wafers in the semiconductor manufacturing process and automatic intervention and control of the production process by non-product wafers, strictly controlling the intervention of non-product wafers in the process production process on product wafers, so as to improve yield and production efficiency.

[0005] The present invention is implemented by the following technical solution: A method for controlling non-product wafers in a semiconductor process, comprising the following steps:

[0006] In the non-product slice type identification module, non-product slices are put in and the type of the put in non-product slices is determined. The types of non-product slices include control slice source slices, control slices, furnace tube control slices, warm-up slices and baffle slices.

[0007] Perform corresponding process flow processing according to the acquired non-product slice type, perform step A on the control slice source slice, perform step B on the control slice, perform step C on the furnace tube control slice, perform step D on the warm-up slice, and perform step E on the baffle slice;

[0008] Step A. Preprocessing the control source film using a machine;

[0009] Step B. The method of putting the control piece into operation includes manual putting and automatic putting. The manual putting or automatic putting of the control piece is selected according to the machine status. When the machine equipment changes the production process parameters, exceeds the specification or undergoes maintenance, the manual putting of the control piece starts the process flow; when the machine equipment periodically monitors the production parameters, the automatic putting of the control piece starts the process flow;

[0010] Step C. When the process flow of the product slice reaches the furnace tube station, the furnace tube control slice and the product slice are bound together, and the furnace tube control slice and the product slice are processed together in the furnace tube equipment;

[0011] Step D. When the machine equipment needs to restore or adjust the working temperature and adjust or switch the process parameter group, use the warm-up sheet for debugging;

[0012] Step E. The baffles include filling baffles and edge baffles. When the machine needs to be fully loaded for process, the filling baffles are used to fill all the empty slots of the machine; when some furnace tube machines are performing process, the edge baffles are used to fill the slots at both ends of the furnace tube to control the product yield.

[0013] In this technical solution, through the efficient and accurate control method of non-product wafers in the semiconductor manufacturing process and the automatic intervention and control of non-product wafers in the production process, the intervention of non-product wafers in the process production process on product wafers is strictly controlled to improve the yield and production efficiency.

[0014] In order to better implement the present invention, further, the method of determining the type of non-product sheets input by the non-product sheet type identification module includes:

[0015] Presetting the use triggering condition of each type of non-product slice in the non-product slice type identification module through the type identification module;

[0016] When the process flow or equipment status of the product piece triggers the above conditions, the corresponding non-product piece is dispatched.

[0017] In order to better implement the present invention, further, step A includes:

[0018] The machines include A1 and A2 machines;

[0019] Step Aa. When the A1 machine uses the control sheet for the first time, first put in the control sheet source sheet LOTA1, and the control sheet source sheet LOTA1 goes to the FORUSE site to be used. At this time, the control sheet LOTA1.01 of the A1 machine is established in batches;

[0020] Step Ab. When the A1 machine needs to use the control sheet again, determine whether the previously invested control sheet source sheet LOTA1 is still available. If so, there is no need to reinvest the control sheet source sheet, and directly split the batch to create the control sheet LOTA1.02. If not, reinvest the control sheet source sheet;

[0021] Step Ac. When the A2 machine needs to use the control slice and the control slices of the A1 machine and the A2 machine are not compatible, it is necessary to re-invest the control slice source slice LOTA2, and move the control slice source slice LOTA2 to the FORUSE waiting site. At this time, the control slice LOTA2.01 of the A2 machine is batched and established.

[0022] In order to better implement the present invention, further, the processing method of automatically putting the control piece into operation in step B includes:

[0023] The automatic input control piece is automatically put into the machine according to the cycle set in the system;

[0024] Obtain the measurement results of the control piece after it is processed on the machine;

[0025] Use optical methods to analyze the measurement results through a statistical process control system, and combine it with the machine control system to determine whether the current state of the machine needs to be adjusted.

[0026] In order to better implement the present invention, further, the processing method of manually inserting the control piece in step B includes:

[0027] When the production process parameters of the machine equipment are changed, the control sheet is used to test whether the parameters of the machine equipment are correct. When the test machine equipment parameters are incorrect, the machine equipment is adjusted until they are adjusted correctly. Only then can the process parameters be used to produce product sheets;

[0028] When the machine equipment exceeds the specification, adjust the process parameters of the machine equipment, only allow the control piece to be manually put into the machine equipment, and perform corresponding measurements on the control piece, until the measurement result of the control piece is correct, the machine equipment is allowed to release and continue to produce product pieces;

[0029] When the machine equipment is maintained, before the machine equipment is put into production again, the control piece is manually inserted into the machine equipment to perform the process flow, and the measurement results are used to determine whether the equipment can continue to be put into production.

[0030] In order to better implement the present invention, further, the process flow of starting the control piece in step B includes:

[0031] Separate the required control slices from the batch of control slice source slices;

[0032] After pre-processing and cleaning the control piece, the data is measured at the front measurement site;

[0033] After the pre-measurement data is correct, the process is carried out on the designated process machine equipment of the required control piece;

[0034] The data is measured at the post-measurement site, and multiple corresponding measurement equipment is selected for measurement according to different parameters. The measurement data reflects the results of the process equipment that the control piece passes through.

[0035] In order to better implement the present invention, further, the operation of cleaning the control sheet includes:

[0036] After cleaning the control piece, the number of cleanings is recorded as 1;

[0037] The number of times the control sheet can be recycled is pre-defined in the system, and the measurement is performed after cleaning to obtain the measurement results;

[0038] Based on the measurement results, it is determined whether the control piece should continue to be used in a circular manner according to the configuration or be downgraded for use in other process flows, or whether the control piece should be downgraded to a baffle piece.

[0039] In order to better implement the present invention, further, step C includes:

[0040] After the furnace tube process is completed, each furnace tube control piece is measured to obtain the measurement results;

[0041] According to the measurement results, the process results of the furnace tube machine for the product batch are obtained and the product batch is processed.

[0042] In order to better implement the present invention, further, a method for obtaining the process results of the furnace tube machine for a product batch according to the measurement results and processing the product batch includes:

[0043] dividing the batches of furnace tube control sheets into batches from the furnace tube control sheet source sheets;

[0044] Configure the position of the furnace tube control piece in the furnace tube according to different process steps;

[0045] Before the measurement of the furnace tube control sheet is completed, the product batch is not allowed to continue the subsequent process;

[0046] Check the measurement results at the measurement process site;

[0047] If the results of all measurement process sites are normal, the furnace tube control sheet and the product sheet are automatically untied, and the measurement results are automatically assigned to the product sheet, and the product sheet continues to carry out the subsequent process; the furnace tube control sheet is marked as used and merged into the furnace tube control sheet source sheet batch;

[0048] If the measurement result is abnormal, the product batch is not allowed to continue the subsequent process. The furnace tube control sheet enters the exception handling process to determine whether the processing result is passed. If so, the product sheet batch is automatically released to continue the subsequent process flow; otherwise, the engineer needs to make a judgment to determine the subsequent rework process of the product sheet; the furnace tube control sheet is marked as used and merged into the furnace tube control sheet source sheet batch.

[0049] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0050] (1) The present invention can accurately and strictly control the interference of non-product wafers with product wafers in the process production flow, so as to improve the yield and production efficiency;

[0051] (2) A portion of the non-product sheets used in the present invention may be derived from discarded product sheets, and the utilization of the non-product sheets can save costs;

[0052] (3) The present invention can accurately feedback equipment data, guide machine equipment maintenance plans and periodic maintenance, and ensure long-term stable operation of the equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] The present invention is further described in conjunction with the following drawings and embodiments, and all the concepts and innovations of the present invention should be regarded as the disclosed contents and the protection scope of the present invention.

[0054] Figure 1 The present invention provides a flow chart of a method for controlling non-product wafers in a semiconductor process.

[0055] Figure 2 A flow chart of controlling a source chip and a control chip in a method for controlling non-product chips in a semiconductor process provided by the present invention.

[0056] Figure 3 The present invention provides a flow chart of a furnace tube control chip source chip and a furnace tube control chip in a method for controlling non-product chips in a semiconductor process.

[0057] Figure 4The present invention provides a flow chart of a warm-up chip in a method for controlling non-product chips in a semiconductor process.

[0058] Figure 5 The present invention provides a flow chart of blocking wafers in a method for controlling non-product wafers in a semiconductor process. DETAILED DESCRIPTION

[0059] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. It should be understood that the described embodiments are only part of the embodiments of the present invention, not all of the embodiments, and therefore should not be regarded as limiting the scope of protection. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technical personnel in this field without making creative work are within the scope of protection of the present invention.

[0060] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "disposed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0061] Embodiment 1:

[0062] This embodiment is based on a method for controlling non-product wafers in a semiconductor process. Figure 1-Figure 5 As shown in the figure, semiconductor measurement processes are mainly divided into the following three categories: film thickness measurement, overlay between layers and other processes. Film thickness measurement is optical measurement or translucent film (Thickness or Optical Critical Dimension, referred to as OCD); overlay between layers (Overlay, referred to as OVL) is the mutual cooperation between measurement processes, and front and back alignment is the most basic requirement; other processes such as wafer substrate thickness, bending warpage, wafer morphology analysis, resistivity, atomic microscope or ultrasonic measurement of step height, etc., and this part of the semiconductor measurement process is applicable to all measurements proposed in this article.

[0063] The method for controlling non-product wafers in the semiconductor process is as follows: First, non-product wafers include control source wafers, control wafers, furnace tube control wafers, warm-up wafers and baffle wafers; by effectively managing and using non-product wafers to intervene in the product wafer production process, the product yield can be maintained and the equipment specifications and processes can be confirmed to be correct, so as to prevent unnecessary scrapping and increase costs.

[0064] like Figure 2 As shown, the wafer type is a dedicated control wafer or a control wafer that has been downgraded in other process steps; a product wafer that does not meet the shipping standards or is scrapped; a control wafer source wafer is a collection of control wafers before they are actually put into the control wafer process, and is essentially also a control wafer; create control wafers: batch the required control wafers from the control wafer source wafers; the number of measurement sites in the control wafer process flow may vary depending on the process, and there may be multiple measurement dimensions such as film thickness, length and width, which are configured according to actual needs; return control wafers: merge the control wafers into the control wafer source wafer batch after the control wafer process ends, and mark the used control wafers as used. After all control wafers in this control wafer source wafer batch have been used once, a unified cleaning cycle is performed.

[0065] Embodiment 2:

[0066] This embodiment is further optimized on the basis of Embodiment 1. In this embodiment, the use trigger conditions of each type of non-product sheet are pre-set in the non-product sheet type identification module through the type identification module; when the process flow or equipment status of the product sheet triggers the said condition, the corresponding non-product sheet is dispatched, and the different scenarios corresponding to the non-product sheet intervening in the product sheet production process are identified to determine the type of non-product sheet involved.

[0067] The other parts of this embodiment are the same as those of Embodiment 1, and thus will not be described in detail.

[0068] Embodiment 3:

[0069] This embodiment is further optimized on the basis of Embodiment 1. In this embodiment, the monitor source lot is controlled: pre-processed in a dedicated monitor source flow, and used to establish monitor lots in batches after arriving at the FORUSE site, and the use of the monitor source lot is controlled:

[0070] When the A1 machine uses the control slice for the first time, it is necessary to first put in the control slice source slice LOTA1 and move the source slice to the FORUSE waiting site. At this time, the control slice LOTA1.01 of the A1 machine can be split into batches;

[0071] When the A1 machine needs to use the control slice again, if there is any remaining control slice source slice LOTA1 that has been invested previously, there is no need to invest the control slice source slice again. Instead, the control slice LOTA1.02 can be directly created by splitting the batch. If there is not enough control slice source slice, invest the control slice source slice again.

[0072] Based on the first point, if the A2 machine needs to use a control piece, and the control pieces of the A1 and A2 machines are not universal, it is necessary to re-invest the control piece source piece LOTA2, and move the source piece to the FORUSE site to be used. At this time, the control piece LOTA2.01 for the A2 machine can be split into batches.

[0073] The other parts of this embodiment are the same as those of Embodiment 1, and thus will not be described in detail.

[0074] Embodiment 4:

[0075] This embodiment is further optimized on the basis of the first embodiment. In this embodiment, the automatically put-in control slice is automatically put into the machine according to the cycle set in the system. This system is a data modeling system, and the corresponding data modeling can be performed according to the actual production situation of the factory. The data model of the non-product slice is also established in the system. At the same time, the non-product slice type identification module is combined to determine the type of the non-product slice put in.

[0076] The monitor lot refers to the monitor lot that actually participates in the process control of the product lot, which is divided into the automatically invested monitor lot and the manually invested monitor lot. The automatically invested monitor lot is automatically invested according to the cycle set in the system to monitor whether the production parameters of the machine are stable. According to the measurement results of the monitor lot after the process is performed on the machine, the optical method is analyzed by the statistical process control system (Statistical Process Control, referred to as SPC), combined with the machine control related system, to comprehensively judge whether the current state of the equipment needs to be adjusted. The measurement results of the monitor lot after the process is performed on the machine refer to the measurement standards defined by the user according to different processes, and the equipment and processes corresponding to the monitor lot. The specific standards can be modeled and modified accordingly in the system according to the actual needs of the user. In addition, the optical method mentioned in this embodiment is not limited to the optical method. All measurement means and methods may be applied according to different processes or equipment, and the final measurement results and data will enter the SPC system for analysis.

[0077] The other parts of this embodiment are the same as those of Embodiment 1, and thus will not be described in detail.

[0078] Embodiment 5:

[0079] This embodiment is further optimized on the basis of the embodiment 1. In this embodiment, the manually-initiated control piece is mainly used in the following situations:

[0080] After new equipment is moved in or the production process parameters of the machine are changed, use the control film to test whether the equipment parameters are correct. Only after they are adjusted correctly can the process parameters be used to produce product films. The judgment is made through the results of post-measurement. If the adjustment is not correct once, use another batch of control films to continue until it is adjusted correctly.

[0081] After the product slices produced by the machine have been measured, they have already exceeded the specification. In order to prevent more product slices from having problems, the machine is put on hold. At this time, the machine process parameters need to be adjusted, and only the control slices are allowed to pass through the machine, and the control slices are measured accordingly. The machine is not allowed to be released until the measurement results of the control slices are correct, and the product slices can continue to be produced. The corresponding measurement is set according to user needs, configured in the system, and the upper and lower limits are configured;

[0082] After the machine equipment is maintained, before it is put back into production, it is necessary to test and evaluate the maintenance results, and verify whether the equipment can produce normally. At this time, a control piece is used to perform the process flow on the equipment, and based on the measurement results, it is determined whether the equipment can continue to be put into production.

[0083] The other parts of this embodiment are the same as those of Embodiment 1, and thus will not be described in detail.

[0084] Embodiment 6:

[0085] This embodiment is further optimized on the basis of embodiment 1. In this embodiment, the process flow of the control sheet is as follows:

[0086] Separate the required control slices from the batch of control slice source slices;

[0087] After pretreatment, cleaning, and pre-measurement stations, pretreatment is defined by the user according to different process technologies and equipment, and only corresponding stations are added to the system flow;

[0088] After the pre-measurement data is correct, the process is carried out on the designated machine that needs the control piece. Pre-measurement refers to the measurement before the control piece is put into the process equipment, and the purpose is to confirm that this batch of control pieces can be used; all measurements in the system have preset upper and lower limits, and the specific values ​​are defined by the customer when modeling; if there is an abnormal piece in the batch, the batch is judged to be abnormal. If the measurement result is abnormal, it will automatically trigger the exception handling process (OCAP). If there is still a problem after OCAP processing, this batch of control pieces cannot be used and will be scrapped accordingly;

[0089] Post-measurement can be carried out on multiple measuring machines for different parameters. All measurement data reflect the results of the process machine that the control piece has passed through. Post-measurement refers to the measurement of the control piece after it has been processed by the process equipment. It is mainly to determine whether the process equipment can achieve the expected results. By comparing with the data from the pre-measurement, it can be calculated whether the process meets the accuracy requirements.

[0090] The other parts of this embodiment are the same as those of Embodiment 1, and thus will not be described in detail.

[0091] Embodiment 7:

[0092] This embodiment is further optimized on the basis of embodiment 6. In this embodiment, the number of times the control sheet is used after cleaning is recorded as 1, and the system predetermines the number of times the control sheet can be recycled; after cleaning, it is measured, and according to the measurement results, it is determined whether the control sheet will continue to be recycled according to the configuration, or be downgraded for use in other process flows or downgraded to a baffle sheet, etc. The predetermined number of times is defined according to user needs when modeling the system. If the measurement result does not exceed the upper and lower limits of the process, it can be recycled; if the measurement result exceeds the upper and lower limits of the process, it will be downgraded to a baffle sheet or other process flows according to the judgment of the engineer.

[0093] The other parts of this embodiment are the same as those of Embodiment 6, and thus will not be described in detail.

[0094] Embodiment 8:

[0095] This embodiment is further optimized on the basis of Embodiment 1. In this embodiment, the furnace tube control sheet (FurnaceMonitor Lot) is based on the special process requirements of the furnace tube equipment. The furnace tube equipment can process multiple batches of product sheets at a time. If each batch needs to be measured after the process is completed, it will greatly affect the production efficiency and bring unnecessary pressure to the production line.

[0096] The batches of furnace tube control sheets are divided into batches from the batches of furnace tube control sheet source sheets. The number of furnace tube control sheets in each batch is determined according to the different processes pre-configured in the system and the number of product batches undergoing furnace tube processing. Figure 3 As shown, the furnace tube control sheet is a special control sheet, and its source can be a dedicated furnace tube control sheet, a scrapped product sheet, or a control sheet that has been used by other equipment but meets the measurement standards of the furnace tube control sheet; the pre-measurement of the furnace tube control sheet and the product sheet are not related to each other, and all measurement processes from the binding of the furnace tube process to the unbinding must be consistent to ensure that the measurement results using the furnace tube control sheet represent the results of the product sheet; according to different processes, the measurement processes and dimensions of the furnace tube control sheet and the product sheet may also be multiple.

[0097] The other parts of this embodiment are the same as those of Embodiment 1, and thus will not be described in detail.

[0098] Embodiment 9:

[0099] This embodiment is further optimized on the basis of Embodiment 8. When the product slice process reaches the furnace tube station, it needs to be bound to the furnace tube control slice. The furnace tube control slice and the product slice are processed together in the furnace tube equipment. The position of the control slice in the furnace tube can be configured according to different process steps. When modeling the furnace tube control slice, the position of the control slice in the furnace tube equipment can be selected. For example, a furnace tube equipment has a total of 150 slots, and the furnace tube control slice can be defined to be placed in slots 50 and 100. After the furnace tube process is completed, each furnace tube control slice needs to be measured, and the measurement results represent the process results of the furnace tube machine for all product batches entering the furnace tube process this time. Before the measurement is completed, the product batch is not allowed to continue the subsequent process; if the results of all measurement process sites are normal, the furnace tube control sheet and the product sheet are automatically untied, and the measurement results are automatically attached to the product sheet, which is convenient for subsequent report analysis and other data statistics. The product sheet continues to proceed with the subsequent process, and the furnace tube control sheet is marked as used and merged into the furnace tube control sheet source sheet batch; abnormal measurement results mean that one sheet exceeds the upper limit or is lower than the lower limit, which is judged as abnormal. The upper and lower limits are set when the system is modeled according to the actual production needs of the user. When the measurement result is abnormal, the product batch is held and no operation is allowed. The furnace tube control sheet enters the exception handling process (Out of Control Action Plan, referred to as OCAP). If the processing result passes, the product sheet batch is automatically released and the subsequent process flow continues; if the OCAP return result is abnormal, the engineer needs to make a judgment and decide on the subsequent return process of the product sheet. The furnace tube control sheet is marked as used and merged into the furnace tube control sheet source sheet batch; After all the control sheets in the furnace tube control sheet source sheet batch have been used once, the furnace tube control sheet source sheet batch cannot continue to be batched out of the furnace tube control sheet batch, and they must be cleaned and measured uniformly. According to the results, the status of each sheet can be managed independently for recycling or downgrading.

[0100] The other parts of this embodiment are the same as those of Embodiment 8, and thus will not be described in detail.

[0101] In another embodiment, the season lot refers to the fact that some equipment in the semiconductor manufacturing process needs to maintain a certain operating temperature and condition. The season lot is used in the following situations:

[0102] The equipment is on standby for a period of time, during which no wafers have been processed in the equipment. Before the process manufacturing needs to be resumed, a warm-up sheet must be used to return the equipment to normal operating temperature and condition before product wafers are allowed to enter the equipment for processing. An example of why a warm-up sheet must be used to return the equipment to normal operating temperature and condition is given. For example, the ideal internal operating temperature of a certain process equipment is 300 degrees Celsius, and the temperature between 280 degrees Celsius and 320 degrees Celsius meets the requirements. In order to restore the internal operating temperature of the equipment to 300 degrees Celsius as much as possible, a warm-up sheet is required for debugging.

[0103] Taking the vertical reactor as an example, it can be used for any process required in wafer manufacturing, such as oxidation, diffusion, annealing and deposition, depending on the configuration. If a configuration is switched, the operating temperature and working conditions of the machine will change. The warm-up plate must be used to adjust the temperature to the appropriate operating temperature before the product wafer is allowed to enter the equipment for processing.

[0104] Some equipment in the wafer manufacturing process can be configured with several sets of process parameters at the same time. When one set of process parameters has not been used for a period of time, a warm-up sheet must be used to debug this set of process parameters to ensure the yield of the product wafer when this set of process parameters is used for production again. An example of using a warm-up sheet to debug this set of process parameters is given: for example, a certain device has three sets of process parameters set, A, B, and C correspond to three different processes respectively; assuming that A, B, and C contain parameters such as temperature, humidity, and pH, and all parameters have ideal values ​​and upper and lower limits; when no batch uses group A parameters for a period of time (this time is defined by the user according to different processes and different equipment), then when there is a batch that needs to use group A parameters again, it is necessary to use a warm-up sheet to debug group A parameters to ensure that all parameters do not exceed the upper and lower limits and are as close to the ideal value as possible.

[0105] When the equipment runs the same process parameter group continuously or cumulatively, exceeding a certain number may cause yield reduction or other problems. At this time, according to different processes and equipment configuration wafer quantity upper limit, when exceeding this upper limit, you can choose to use the warm-up chip to debug the process parameter group of the equipment.

[0106] like Figure 4 As shown, the warm-up sheet can be a dedicated warm-up sheet, or it can be other used control sheets or product sheets that have been downgraded, or a warm-up sheet used in other equipment can also be used in another equipment; Figure 4 All types of warm-up sheets must meet the inspection standards before the batch can be put into use. After all the warm-up sheets in the batch have been used, the entire batch will be recycled and all actions such as awards can be performed manually.

[0107] In another embodiment, the dummy lot usually uses some scrapped wafers, which can be divided into the following two types according to the usage:

[0108] Fill Dummy: Some special machines require full loading for the process. If the machine is not full, it needs to be filled with fill dummy.

[0109] Side Dummy: In order to control the product yield, when some machines are performing processes, side dummy sheets are placed at the positions where the position parameters of the two ends of the cavity are unstable, to ensure that the product piece is processed in the part with the most stable parameters in the cavity of the equipment.

[0110] like Figure 5 As shown, the baffles are divided into dedicated baffles, downgraded non-product baffles, and scrapped or unusable product baffles.

[0111] The above are only preferred embodiments of the present invention and are not intended to limit the present invention in any form. Any simple modifications or equivalent changes made to the above embodiments based on the technical essence of the present invention fall within the protection scope of the present invention.

Claims

1. A method for controlling non-product wafers in a semiconductor process, characterized in that: The following steps are involved: Input non-product sheets into the non-product sheet type identification module and determine the type of non-product sheets input, wherein the non-product sheet types include control sheet source sheets, control sheets, furnace tube control sheets, warm-up sheets and baffle sheets; Perform corresponding process flow processing according to the acquired non-product sheet types, perform step A operation on the control sheet source sheets, perform step B operation on the control sheets, perform step C operation on the furnace tube control sheets, perform step D operation on the warm-up sheets, and perform step E operation on the baffle sheets; Step A. Pre-process the control sheet source sheets using a machine; Step B. The method of putting the control sheet into operation includes manual operation and automatic operation. The manual operation or automatic operation of the control sheet is selected according to the machine status. When the machine equipment changes the production process parameters, exceeds the specification or undergoes maintenance, the control sheet is manually put into operation to start the process flow; when the machine equipment periodically monitors the production parameters, the control sheet is automatically put into operation to start the process flow; Step C. When the process flow of the product sheet reaches the furnace tube station, the furnace tube control sheet and the product sheet are bound, and the furnace tube control sheet and the product sheet are processed together in the furnace tube equipment; Step D. When the machine equipment needs to restore or adjust the operating temperature and adjust or switch the process parameter group, the warm-up sheet is used for debugging; Step E. The baffles include filling baffles and edge baffles. When the machine needs to be fully loaded for process processing, the filling baffles are used to fill all vacant slots of the machine; when certain furnace tube machines are performing process processing, the edge baffles are used to fill the slots at both ends of the furnace tube when controlling the product yield.

2. A method for controlling non-product wafers in a semiconductor process according to claim 1, characterized in that: The method for determining the type of non-product sheets to be put into use through a non-product sheet type identification module includes: pre-setting the use trigger conditions of each type of non-product sheet through a type identification module in the non-product sheet type identification module; when the process flow or equipment status of the product sheet triggers the said condition, dispatching the corresponding non-product sheet.

3. The method for controlling non-product wafers in a semiconductor process according to claim 1, characterized in that: The step A comprises: the machines include the A1 machine and the A2 machine; step Aa. when the A1 machine uses the control slice for the first time, the control slice source slice LOTA1 is first put in, and the control slice source slice LOTA1 is moved to the site to be used, and the control slice LOTA1.01 of the A1 machine is then batched and established; Step Ab. When the A1 machine needs to use the control sheet again, determine whether the previously invested control sheet source sheet LOTA1 is still available. If so, there is no need to reinvest the control sheet source sheet, and directly split the batch to create the control sheet LOTA1.

02. If not, reinvest the control sheet source sheet; Step Ac. When the A2 machine needs to use the control slice and the control slices of the A1 machine and the A2 machine are not compatible, it is necessary to re-invest the control slice source slice LOTA2 and move the control slice source slice LOTA2 to the site to be used. At this time, the control slice LOTA2.01 of the A2 machine is batched and established.

4. The method for controlling non-product wafers in a semiconductor process according to claim 1, characterized in that: The processing method of automatically inserting the control sheet in step B includes: the automatically inserted control sheet is automatically inserted into the machine according to a cycle set in the system; Obtain the measurement results of the control piece after the process is performed on the machine; Use optical methods to analyze the measurement results through a statistical process control system, and combine with the machine control system to determine whether the current state of the machine needs to be adjusted.

5. The method for controlling non-product wafers in a semiconductor process according to claim 1, characterized in that: The processing method for manually inserting the control piece in step B includes: when the machine equipment changes the production process parameters, using the control piece to test whether the machine equipment parameters are correct, and adjusting the machine equipment when it is tested that the test machine equipment parameters are incorrect, until the adjustment is correct, the process parameters can be used to produce product pieces; when the machine equipment exceeds the specifications, the process parameters of the machine equipment are adjusted, and only the control piece is allowed to be manually inserted into the machine equipment, and the control piece is measured accordingly, until the measurement result of the control piece is correct, the machine equipment is allowed to release and continue to produce product pieces; after the machine equipment is maintained, before the machine equipment is put back into production, the control piece is manually inserted into the machine equipment to carry out the process flow, and it is judged whether the equipment can continue to be put into production based on the measurement results.

6. The method for controlling non-product wafers in a semiconductor process according to claim 1, characterized in that: The process flow of starting the control piece in step B includes: separating the required control piece from the batch of control piece source pieces; measuring data at the front measurement station after pre-processing and cleaning the control piece; after the front measurement data is correct, performing the process on the process machine equipment of the specified required control piece; measuring data at the back measurement station, selecting corresponding multiple measurement machines and equipment for different parameters for measurement, and reflecting the results of the process machine equipment that the control piece has passed through through the measurement data.

7. A method for controlling non-product wafers in a semiconductor process according to claim 6, characterized in that: The operation of cleaning the control plate includes: recording the number of cleanings as 1 after cleaning the control plate; predetermining the number of times the control plate can be recycled in the system, measuring it after cleaning, and obtaining the measurement results; determining based on the measurement results whether the control plate should continue to be recycled according to the configuration or be downgraded for use in other process flows, or downgrading the control plate to a baffle plate.

8. The method for controlling non-product wafers in a semiconductor process according to claim 1, characterized in that: The step C comprises: after the furnace tube process is completed, measuring each furnace tube control sheet to obtain the measurement result; obtaining the process result of the furnace tube machine for the product batch according to the measurement result and processing the product batch.

9. The method for controlling non-product wafers in a semiconductor process according to claim 8, characterized in that: The method for obtaining the process results of the furnace tube machine for the product batch according to the measurement results and processing the product batch includes: dividing the furnace tube control sheet batch from the furnace tube control sheet source sheet; configuring the position of the furnace tube control sheet in the furnace tube according to different process steps; Before the measurement of the furnace tube control sheet is completed, the product batch is not allowed to continue the subsequent process; Check the measurement results at the measurement process site; If the results of all measurement process sites are normal, the furnace tube control sheet and the product sheet are automatically untied, and the measurement results are automatically attached to the product sheet, and the product sheet continues to proceed with the subsequent process; mark the furnace tube control sheet as used and merge it into the furnace tube control sheet source sheet batch; If the measurement result is abnormal, the product batch is not allowed to continue the subsequent process. The furnace tube control sheet enters the exception handling process to determine whether the processing result is passed. If so, the product sheet batch is automatically released to continue the subsequent process flow; otherwise, the engineer needs to make a judgment to determine the subsequent rework process of the product sheet; the furnace tube control sheet is marked as used and merged into the furnace tube control sheet source sheet batch.

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