Evaporation film thickness SPC process monitoring feedback adjustment method and device and storage medium

Abstract

The invention discloses an evaporation film thickness SPC process monitoring feedback adjustment method and device and a storage medium, and the method comprises the steps: building a film thickness result adjustment feedback model based on historical data in combination with an actual rule relation between an actual production film thickness measurement result and a device parameter; considering the stability and risk of equipment and a process, and establishing a film thickness compensation coefficient to ensure the stability of an adjustment result; and after a measurement result is transmitted to the SPC system, the SPC system adjusts a feedback model based on a film thickness result, calculates related parameter suggested adjustment amount, and feeds back and notifies a technologist. According to the invention, based on the historical measurement result and the equipment parameter adjustment result, the film thickness adjustment compensation coefficient model is established, each measurement result provides the film thickness parameter compensation amount, it is ensured that the next film thickness measurement result tends to the target value, and it is ensured that the film thickness can be maintained near the target value in a long time range. Triggering of abnormal film thickness is reduced, occurrence of disqualification and continuous output are reduced, the project yield is prompted, and cost is reduced.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor manufacturing technology, and in particular to a method, device and storage medium for monitoring feedback adjustment of SPC process of evaporated film thickness. Background Art

[0002] At present, OLED technology accounts for an increasing proportion in the display industry, and is increasingly widely used in wearables, mobile phones, and mid-sized cars. At the same time, the core of OLED technology lies in the evaporation of organic film layers. In the manufacturing process of OELD panels, the stability and yield of the evaporation process are the top priorities of OLED factories. In the actual production process, due to the limitations of the evaporation process itself, the final cost of the product is mainly concentrated in the evaporation process. How to ensure the stability and yield of the production results of the evaporation process is the key prerequisite for reducing costs and increasing efficiency in the OLED industry.

[0003] Generally, in the production process, after all the film layers of the evaporation process are completed, the detection equipment is used for measurement. The measuring equipment transmits the measurement results to SPC. The SPC system monitors and judges according to the specifications & control limits and judgment rules set in the monitoring parameter control chart. If the judgment is not triggered, no feedback will be given, and the process unit will not be notified by email or other means to make adjustments, even if it may be on the edge of the specification limit. If the judgment is triggered, the process department will be notified to confirm and adjust and improve. After receiving the results, the person in charge of the process confirms the measurement results and checks the production process parameter results and related possible reasons, and then calculates the parameter compensation amount based on the parameter results, and adjusts the parameter settings on the equipment side to ensure that the subsequent film thickness results remain within the stable range. This process, from the end of the film thickness measurement result measurement to the adjustment of the relevant person in charge, takes a long time, especially the person in charge needs to calculate the compensation adjustment amount based on the film thickness measurement results & equipment parameter results. If the process takes too long, it may cause the continuous output of unqualified products in this process or even flow to the back stage, resulting in unnecessary product scrapping, increasing production costs and reducing yield.

[0004] At the same time, in the process of actual film thickness monitoring and adjustment, due to occasional fluctuations in the equipment, the film thickness will not be adjusted to the target value in one adjustment process, but will need to be adjusted repeatedly to gradually adjust to the target. However, in the actual monitoring process, if there is no result that triggers the abnormality, the SPC system will not notify the process unit, and personnel need to actively check and compare in the SPC system, resulting in the inability of personnel to adjust the results in real time, causing adjustment delays. When the notification is received, the product is out of specification due to the triggering of the abnormality, resulting in scrapping. The existing monitoring and adjustment mechanism for the thickness of evaporated films has a long waiting time and manual calculation time for the adjustment results, which leads to the continuous output of unqualified products and flows to the back-end, causing waste and increasing costs. Therefore, the current monitoring and adjustment method for the thickness of evaporated films can no longer meet the needs of actual production monitoring in factories. How to improve the efficiency of the real-time adjustment results of the thickness of evaporated films and know the adjustment values ​​of the parameters related to the thickness when the film thickness measurement results come out has become a key to improving the yield and reducing costs. The purpose of the present invention is to solve this kind of problem. Summary of the invention

[0005] The present invention provides a method, device and storage medium for monitoring feedback adjustment of SPC process of evaporation film thickness, which can at least solve one of the technical problems in the background technology.

[0006] To achieve the above object, the present invention adopts the following technical solutions: A method for monitoring and adjusting the SPC process of evaporation film thickness, comprising the following steps: Based on the basic rules of evaporation film thickness adjustment, combined with the actual relationship between actual production film thickness measurement results and equipment parameters, a film thickness result adjustment feedback model based on historical data is established; Combined with the actual historical rules, considering the stability and risks of equipment and process, the film thickness compensation coefficient is established to ensure the stability of the adjustment results; After the measurement results are transmitted to the SPC system, the SPC system adjusts the feedback model based on the film thickness results, calculates the recommended adjustment amounts for the relevant parameters, and provides feedback to the process personnel.

[0007] Furthermore, a film thickness result adjustment feedback model based on historical data is established, including a step of calculating the offset of the evaporation film thickness measurement result. Calculate the film thickness deviation, ΔA, based on the film thickness results detected by the equipment and the target value set for the corresponding product and film layer requirements. m =Mean (实际) -Target (膜厚) ; The thickness of the evaporated film is the function of the evaporation material, the film forming temperature and the film forming time: ∂A=λ1*∂T c +(1-λ1)*∂t A m is the film thickness result, λ1 is the temperature coefficient, T c is the film forming temperature, t is the film forming time; It also includes the T corresponding to the product that obtains the current film thickness measurement result. c and t, as follows, Based on the film thickness measurement results, the film forming temperature T corresponding to the product of the FDC system is obtained through the interface. cand time t, and obtain the target value T of the current corresponding product, equipment, chamber temperature and time c 1, t1; that is: ΔT c =T c - Target(temperature),Δt=t-Target(time) .

[0008] Furthermore, the film thickness compensation coefficient is established, including taking into account the fluctuation of production equipment, the fluctuation of actual adjustment results and theoretical adjustment results. In order to ensure the stability and risk of automatic adjustment results, the stability & risk parameter coefficient is considered to be added: ∂A=φ 1 *l 1 *∂T c +φ 2 *(1-l 1 )*∂t ; φ1、φ2 It is the temperature and time supplement coefficient summarized from the historical adjustment result data model;

[0009]

[0010] Right now:

[0011] φ1 is the coefficient of the temperature adjustment and film thickness variation law of the same product, equipment, and chamber, which takes into account the potential risk that the adjustment result may fluctuate in the opposite direction of the expected adjustment result in the actual process; φ2 is the coefficient of the temperature adjustment and time variation law of the same product, equipment, and chamber, which takes into account the potential risk that the actual adjustment result of the actual process may warn of the opposite adjustment result; at the same time, considering the fluctuation differences of the process at different times, φ1 and φ2 need to be updated and adjusted regularly, and dynamically adjusted and updated based on the latest historical time.

[0012] Furthermore, the SPC system adjusts the feedback model based on the film thickness results and calculates the recommended adjustment amounts for related parameters, including When the current product film thickness measurement result is A, the film thickness offset is ΔA m , the corresponding temperature and time compensation results are: ΔT c =

[0013] Δt=

[0014] Tc &t Expected adjustment result value: T c(预期) =T c +ΔT c =T c -

[0015] t (预期) =t+Δt=t-

[0016] Based on the model, the SPC system calculates the recommended adjustment results for temperature and time compensation, and feeds back the calculated results to the user by email or other means, for the user to refer to and decide whether to make adjustments.

[0017] On the other hand, the present invention further discloses a computer-readable storage medium storing a computer program, wherein when the computer program is executed by a processor, the processor executes the steps of the above method.

[0018] On the other hand, the present invention further discloses a computer device, including a memory and a processor, wherein the memory stores a computer program, and when the computer program is executed by the processor, the processor executes the steps of the above method.

[0019] It can be seen from the above technical scheme that the present invention provides a method for monitoring feedback and adjusting the SPC process of the thickness of a vapor deposited film. The method is based on the basic law of the adjustment of the thickness of the vapor deposited film, combined with the actual regular relationship between the actual production film thickness measurement results and the equipment parameters, to establish a feedback model for adjusting the film thickness results based on historical data. Combined with the actual historical laws, considering the stability and risks of the equipment and process, a film thickness compensation coefficient is established to ensure the stability of the adjustment results. After the measurement results are transmitted to the SPC system, the SPC system calculates the recommended adjustment amount of the relevant parameters based on the adjustment model, and feeds back to notify the process, thereby reducing the parameter calculation time of the process personnel and improving efficiency. At the same time, the equipment capacity and process stability are different at different times and stages, and the compensation coefficient model needs to be re-established regularly as needed.

[0020] Specifically, the present invention proposes a new SPC process monitoring feedback adjustment method for vapor deposition film thickness. Based on historical measurement results and equipment parameter adjustment results, a film thickness adjustment compensation coefficient model is established to provide a film thickness parameter compensation amount for each measurement result, thereby ensuring that the next film thickness measurement result tends to the target value, ensuring that the film thickness can be maintained near the target value for a long time, reducing the triggering of film thickness anomalies, reducing the occurrence of unqualified products and continuous output, improving engineering yield, and reducing costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a flowchart of the present invention; Figure 2 is the film thickness measurement result and T c Temperature result trend graph. DETAILED DESCRIPTION

[0022] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, 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. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments.

[0023] like Figure 1 As shown, the SPC process monitoring feedback adjustment method for the evaporation film thickness described in this embodiment includes the following steps: S1, calculation of offset of evaporation film thickness measurement results; In the panel display industry, the evaporation process is the core key process step, providing the light-emitting layer and compensation layer for the entire panel display product. According to the film thickness results detected by the equipment and the target values ​​set for the corresponding products and film layer requirements, the film thickness deviation, ΔA, is calculated. m =Mean (实际) -Target (膜厚) .

[0024] It is known that the thickness of the evaporated film is a function of the evaporation material, the film forming temperature and the film forming time: ∂A=λ1*∂T c +(1-λ1)*∂t A m is the film thickness result, λ1 is the temperature coefficient, Tc is the film forming temperature, and t is the film forming time.

[0025] S2. Obtain the T corresponding to the product with the current film thickness measurement result c and t Based on the film thickness measurement results, the film forming temperature T corresponding to the product of the FDC system is obtained through the interface. c and film forming time t, and obtain the target value T of the current corresponding product, equipment, chamber temperature and film forming time c 1, t1. That is: ΔT c =T c -Target (温度) ,Δt=t-Target (成膜时间) 。

[0026] S3, Data Model Definition Taking into account the fluctuations of production equipment, the fluctuations of actual adjustment results and theoretical adjustment results, in order to ensure the stability and risk of automatic adjustment results, consider adding parameter stability & risk coefficient: ∂A=φ 1 *l 1 *∂T c +φ 2 *(1-l 1 )*∂t。

[0027] φ1、φ2 It is the temperature and film-forming time supplementary coefficient summarized from the historical adjustment parameter result data model.

[0028]

[0029]

[0030] Right now:

[0031] φ1 is the coefficient of temperature adjustment and film thickness variation of the same product, equipment, and chamber, taking into account the potential risk that the adjustment result in the actual process may fluctuate in the opposite direction of the expected adjustment result; φ2 is the coefficient of film formation time adjustment and film thickness variation of the same product, equipment, and chamber, taking into account the potential risk that the actual adjustment result in the actual process may be the opposite of the warning adjustment result. At the same time, considering the fluctuation difference of the process in different time periods, φ1 and φ2 need to be regularly updated, verified and adjusted, and dynamically adjusted and updated based on the latest historical data.

[0032] S4. Suggested Adjustment Results When the current product film thickness measurement result is A, the film thickness offset is ΔA m , the corresponding temperature and time compensation results are: ΔT c =

[0033] Δt=

[0034] T c &t Expected adjustment result value: T c(预期) =T c +ΔT c =T c -

[0035] t (预期) =t+Δt=t-

[0036] Based on the model, the SPC system calculates the temperature and time compensation adjustment results, and sends the calculated results to the user by email or other means, and the user makes a reference to whether to make adjustments. This reduces the need for users to calculate and output adjustment results based on measurement results.

[0037] like Figure 2 In the actual process, the film thickness measurement results are not adjusted in the direction or degree expected by the temperature adjustment results, and process fluctuations are inevitable. Therefore, based on the compensation coefficient, it can be ensured that the film thickness results due to process fluctuations are out of specification. This method can avoid excessive fluctuations in film thickness results between batches and ensure the stability of the process.

[0038] In practice, in the production process of OLED panel display, based on the adjustment law of evaporation film thickness, the function of film thickness, temperature and time is defined. Considering the fluctuation of equipment and the fact that the actual measurement results in the actual process are not completely consistent with the expected adjustment results, and even the situation of unexpected reverse adjustment in the actual process, it is necessary to add risk factors to improve the instability and risk of adjustment results. Based on the historical data of temperature, time and actual film thickness results, a mathematical model is established to formulate risk correlation coefficients. The film thickness adjustment law should consider the risk factor. When SPC receives the film thickness measurement data and obtains the temperature and time results of the product during production, it calculates the recommended adjustment amount of temperature and time based on the film thickness adjustment law function considering the risk factor. Feedback the recommended adjustment amount to the technical department in the form of email or other forms. The technical department adjusts the parameters based on the recommended adjustment amount fed back by SPC. There is no need to manually calculate the output parameter adjustment amount, which improves efficiency and reduces the output of defective products.

[0039] On the other hand, the present invention further discloses a computer-readable storage medium storing a computer program, wherein when the computer program is executed by a processor, the processor executes the steps of the above method.

[0040] On the other hand, the present invention further discloses a computer device, including a memory and a processor, wherein the memory stores a computer program, and when the computer program is executed by the processor, the processor executes the steps of the above method.

[0041] In another embodiment provided in the present application, a computer program product including instructions is also provided, which, when executed on a computer, enables the computer to execute any of the evaporation film thickness SPC process monitoring feedback adjustment methods in the above embodiments.

[0042] It is understandable that the system, device and storage medium provided in the embodiments of the present invention correspond to the method provided in the embodiments of the present invention, and the explanation, examples and beneficial effects of the relevant contents can refer to the corresponding parts in the above methods.

[0043] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented using software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the process or function described in the embodiment of the present application is generated in whole or in part. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions may be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions may be transmitted from a website site, a computer, a server or a data center by wired (e.g., coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) mode to another website site, computer, server or data center. The computer-readable storage medium may be any available medium that a computer can access or a data storage device such as a server or a data center that includes one or more available media integrated. The available medium may be a magnetic medium (e.g., a floppy disk, a hard disk, a tape), an optical medium (e.g., a DVD), or a semiconductor medium (e.g., a solid-state drive Solid State Disk (SSD)), etc.

[0044] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0045] Each embodiment in this specification is described in a related manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the system embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment.

[0046] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for monitoring and feedback adjustment of SPC process of evaporation film thickness, characterized in that: The following steps are included: Based on the basic rules of evaporation film thickness adjustment, combined with the actual relationship between actual production film thickness measurement results and equipment parameters, a film thickness result adjustment feedback model based on historical data is established; Combined with the actual historical rules, considering the stability and risks of equipment and process, the film thickness compensation coefficient is established to ensure the stability of the adjustment results; After the measurement results are transmitted to the SPC system, the SPC system adjusts the feedback model based on the film thickness results, calculates the recommended adjustment amounts for the relevant parameters, and provides feedback to the process personnel.

2. The SPC process monitoring feedback adjustment method for evaporation film thickness according to claim 1, characterized in that: Establishing a film thickness result adjustment feedback model based on historical data includes the steps of calculating the offset of the evaporation film thickness measurement results. Calculate the film thickness deviation, ΔA, based on the film thickness results detected by the equipment and the target value set for the corresponding product and film layer requirements. m =Mean (实际) -Target (膜厚) ; The thickness of the evaporated film is the function of the evaporation material, the film forming temperature and the film forming time: ∂A=λ1*∂T c +(1-λ1)*∂t A m is the film thickness result, λ1 is the temperature coefficient, Tc is the film forming temperature, and t is the film forming time; It also includes the T corresponding to the product that obtains the current film thickness measurement result. c and t, as follows, Based on the film thickness measurement results, the film forming temperature T corresponding to the product of the FDC system is obtained through the interface. c and time t, and obtain the target value T of the current corresponding product, equipment, chamber temperature and time c 1, t1; that is: ΔT c =T c - Target (temperature), Δt = t-Target (time) 。 3. The SPC process monitoring feedback adjustment method for evaporation film thickness according to claim 2, characterized in that: Establishing the film thickness compensation coefficient includes taking into account the fluctuation of production equipment, the fluctuation of actual adjustment results and theoretical adjustment results. In order to ensure the stability and risk of automatic adjustment results, consider adding stability & risk parameter coefficients: ∂A=φ 1 *λ 1 *∂T c +φ 2 *(1-λ 1 )*∂t ； φ1、φ2 It is the temperature and time supplement coefficient summarized from the historical adjustment result data model; Right now: φ1 is the coefficient of the temperature adjustment and film thickness variation law of the same product, equipment, and chamber, which takes into account the potential risk that the adjustment result may fluctuate in the opposite direction of the expected adjustment result in the actual process; φ2 is the coefficient of the temperature adjustment and time variation law of the same product, equipment, and chamber, which takes into account the potential risk that the actual adjustment result of the actual process may warn of the opposite adjustment result; at the same time, considering the fluctuation differences of the process at different times, φ1 and φ2 need to be updated and adjusted regularly, and dynamically adjusted and updated based on the latest historical time.

4. The SPC process monitoring feedback adjustment method for evaporation film thickness according to claim 3, characterized in that: The SPC system adjusts the feedback model based on the film thickness results and calculates the recommended adjustment amounts for related parameters, including When the current product film thickness measurement result is A, the film thickness offset is ΔA m , the corresponding temperature and time compensation results are: ΔT c = Δt= T c &t Expected adjustment result value: T c(预期) =T c +ΔT c =T c - t (预期) =t+Δt=t- Based on the model, the SPC system calculates the recommended adjustment results for temperature and time compensation, and feeds back the calculated results to the user by email or other means, for the user to refer to and decide whether to make adjustments.

5. A computer-readable storage medium storing a computer program, wherein when the computer program is executed by a processor, the processor is caused to perform the steps of the method according to any one of claims 1 to 4.

6. A computer device comprising a memory and a processor, wherein the memory stores a computer program, and when the computer program is executed by the processor, the processor executes the steps of the method according to any one of claims 1 to 4.

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