Photoresist removal method and device

Abstract

The present invention provides a photoresist removal method and device, comprising: a wet stripping step: using a substrate conveying device to convey a substrate into a wet stripping chamber to remove photoresist from the substrate surface; a defect detection step: using a defect detection device to detect the total amount of photoresist residue on the substrate surface; if the total amount of photoresist residue is lower than a preset value, performing a wet stripping step and a defect detection step for the next substrate; if the total amount of photoresist residue is higher than a preset value, performing a stripping rework step and repeating the defect detection step; wherein the stripping rework step comprises: using the substrate conveying device to convey the substrate again into the wet stripping chamber to remove the photoresist residue on the substrate surface. The present invention can detect whether there is photoresist residue on the substrate online, and automatically select a rework time and a spray pipe arm swing program based on the distribution of the photoresist residue area and the amount of photoresist residue, thereby improving rework efficiency.

Description

Technical Field

[0001] The invention belongs to the field of semiconductor integrated circuit manufacturing and relates to a photoresist removal method and device. Background Art

[0002] As semiconductor device feature sizes continue to shrink, wet stripping processes are becoming increasingly important, enabling precise control of photoresist removal and minimizing raw material loss. Wet stripping offers a wide range of adaptability, requires minimal time, and causes minimal damage to silicon wafers, making it suitable for most photoresist and substrate materials.

[0003] In the wet stripping process, due to fluctuations in the stripping solution temperature, fluctuations in the substrate photoresist thickness, or changes in the stripping solution concentration, the stripping ability of the stripping solution will change, which may cause photoresist residues on the surface of the substrate. After testing, substrates with photoresist residues need to be stripped again, which seriously affects product output.

[0004] As the demand for semiconductor components continues to increase, there are higher requirements for high output of semiconductor components without expanding production capacity. Rework efficiency is an important reference indicator for testing product output.

[0005] Currently, the industry primarily uses immersion strippers and single-wafer strippers. Regardless of whether a batch of products is stripped using an immersion stripper or a single-wafer stripper, after the entire batch has completed the stripping process, the products are sent to an inspection machine for defect detection (to check for the presence of photoresist residue). Substrates with photoresist residue must be distinguished from normal substrates, and then the abnormal substrates are stripped and reworked. Because the residual photoresist area and amount on abnormal substrates vary, the rework process must accommodate different residual conditions, resulting in a generally longer rework time. Substrate identification, handling, and rework waste significant time, resulting in low rework efficiency and impacting output.

[0006] In the single-wafer stripping process, the main factors affecting rework efficiency are the time required to distinguish substrates and the rework process. How to avoid manual separation of substrates and accurately control the rework process time are major challenges facing wet stripping. Summary of the Invention

[0007] In view of the above-mentioned shortcomings of the prior art, the object of the present invention is to provide a photoresist removal method and device for solving the problems of low rework efficiency and inability to accurately control the rework time in the prior art.

[0008] To achieve the above-mentioned and other related purposes, the present invention provides a method for removing photoresist, comprising the following steps:

[0009] Wet stripping step: using a substrate conveying device to convey the substrate into a wet stripping chamber to remove the photoresist on the surface of the substrate;

[0010] Defect detection step: using a defect detection device to detect the total amount of photoresist residue on the surface of the substrate, if the total amount of photoresist residue is lower than a preset value, then performing a wet stripping step and a defect detection step for the next substrate; if the total amount of photoresist residue is higher than the preset value, then performing a stripping rework step and repeating the defect detection step;

[0011] The debonding and rework step includes: using the substrate conveying device to convey the substrate to the wet debonding chamber again to remove the photoresist remaining on the surface of the substrate.

[0012] Optionally, the defect detection device detects the total amount of photoresist residue including the following steps:

[0013] Taking a photo of the substrate;

[0014] Based on the photographed photos, the size of each residual region is measured and the area of each residual region and the residual photoresist thickness at the center of the corresponding residual region are calculated, where the area of the nth residual region is S n , the thickness of the residual photoresist at the center of the nth residual area is H n , n is an integer, and n≥0;

[0015] Calculate the total photoresist residue P, where P = S1*H1+S2*H2+…+S n *H n .

[0016] Optionally, the method further includes a step of calculating the time required for debonding and reworking the substrate, and performing the debonding and reworking step based on the time required for debonding and reworking.

[0017] Optionally, the time required for the desizing and rework is t=P / {(S1+S2+...+S n )*V}, where P is the total amount of photoresist residue, S n is the area of the nth residual area, V is the average rate of debonding per unit area, n is an integer, and n≥0.

[0018] Optionally, in the stripping and rework step, a stripping solution is supplied based on the distribution of the photoresist residual area.

[0019] Optionally, the substrate sheet includes at least two areas arranged in sequence from the center of the substrate sheet to the edge of the substrate sheet. When the photoresist residue area is only distributed in one of the areas, in the degumming and rework step, the degumming liquid supply arm only swings back and forth between the inner edge and the outer edge of the area with photoresist residue; when the photoresist residue area is distributed in at least two areas, the degumming liquid supply arm swings back and forth between the inner edge of the innermost area with photoresist residue and the outer edge of the outermost area with photoresist residue.

[0020] Optionally, the substrate piece includes an inner circle area, a middle circle area and an outer circle area distributed in sequence from the center of the substrate piece to the edge of the substrate piece, wherein the inner edge of the inner circle area is the center of the substrate piece, and the distance between the outer edge of the inner circle area and the center of the substrate piece is one-third of the radius of the substrate piece; the inner edge of the middle circle area coincides with the outer edge of the inner circle area, and the distance between the outer edge of the middle circle area and the center of the substrate piece is two-thirds of the radius of the substrate piece; the inner edge of the outer circle area coincides with the outer edge of the middle circle area, and the outer edge of the outer circle area is the outer edge of the substrate piece.

[0021] Optionally, the method further includes calculating the time required for photoresist stripping and reworking of the substrate based on the distribution of the photoresist residual area, and performing the photoresist stripping and reworking step based on the time required for the photoresist stripping and reworking.

[0022] Optionally, calculating the time required for the stripping and rework of the substrate based on the distribution of the photoresist residual area includes: calculating the time required for the stripping and rework of different areas of the substrate, and taking the time required for the stripping and rework of the area with the longest stripping and rework time as the stripping and rework time of the substrate.

[0023] Optionally, calculating the time required for de-bonding and rework of different areas of the substrate comprises the following steps:

[0024] Providing an experimental substrate, measuring the thickness of the photoresist at m points in an i-th region of the experimental substrate, wherein i is an integer greater than 0 and m is an integer greater than 1;

[0025] Placing the experimental substrate into the wet stripping chamber for a preset time T to remove a portion of the photoresist on the surface of the experimental substrate;

[0026] again measuring the thickness of the photoresist at the m points in the i-th region of the experimental substrate;

[0027] Adding the photoresist thickness changes before and after photoresist stripping at the m points in the i-th region of the experimental substrate and dividing the sum by m and T to obtain an average photoresist stripping rate for the i-th region of the experimental substrate;

[0028] In the defect detection step, the defect detection device is used to detect the total amount of photoresist residue in the i-th area of the substrate, and the total amount of photoresist residue in the i-th area of the substrate is divided by the total photoresist residue area of the i-th area of the substrate and the average debonding rate of the i-th area of the experimental substrate to obtain the time required for debonding rework of the i-th area of the substrate.

[0029] Optionally, using the defect detection device to detect the total amount of photoresist residue in the i-th area of the substrate comprises the following steps:

[0030] Taking a photo of the substrate;

[0031] Based on the photographed photos, the size of each residual region in the i-th region of the substrate is measured and the area of each residual region and the residual photoresist thickness at the center of the corresponding residual region are calculated, where the area of the n-th residual region is S n , the thickness of the residual photoresist at the center of the nth residual area is H n , n is an integer, and n≥0;

[0032] Calculate the total photoresist residue P in the i-th area of the substrate, where P = S1*H1+S2*H2+…+S n *H n .

[0033] The present invention also provides a photoresist removal device, comprising:

[0034] A substrate sheet conveying device, used for conveying substrate sheets;

[0035] Wet stripping chamber, used to remove photoresist from the surface of the substrate;

[0036] A defect detection device is used to detect the total amount of photoresist residue on the surface of the substrate and compare the total amount of photoresist residue with a preset value. If the total amount of photoresist residue is lower than the preset value, the substrate conveying device is controlled by a control module connected to the defect detection device, the wet removal chamber and the substrate conveying device to convey the next substrate to the wet stripping chamber; if the total amount of photoresist residue is higher than the preset value, the substrate conveying device is controlled by the control module to convey the substrate to the wet stripping chamber again to perform a stripping rework step, and after the stripping rework, the substrate is conveyed to the defect detection device again for photoresist residue detection.

[0037] Optionally, the defect detection device further includes a camera module connected to the control module for taking pictures of the substrate, a size measurement module for measuring the size of each residual area and calculating the area of the residual area, and a thickness measurement module for measuring the thickness of the residual photoresist.

[0038] Optionally, the control module is further configured to calculate a time required for debonding and reworking the substrate piece, and control a debonding and reworking time of the substrate piece in the wet debonding chamber based on the time required for debonding and reworking.

[0039] Optionally, the time required for the desizing and rework is t=P / {(S1+S2+...+S n )*V}, where P is the total amount of photoresist residue, S n is the area of the nth residual area, V is the average rate of debonding per unit area, n is an integer, and n≥0.

[0040] Optionally, the wet stripping chamber further includes a stripping liquid supply arm, and the control module is further configured to control the stripping liquid supply arm to supply the stripping liquid to a preset area of the substrate based on the distribution of the photoresist residue area.

[0041] Optionally, the control module is further configured to calculate a time required for photoresist stripping and rework of the substrate based on a distribution of photoresist residue areas, and control a time required for photoresist stripping and rework of the substrate in the wet photoresist stripping chamber based on the time required for photoresist stripping and rework.

[0042] As described above, the photoresist removal method and apparatus of the present invention can detect online whether there is photoresist residue on a substrate, automatically measure the size of the photoresist residue area, calculate the residual area and thickness of the photoresist residue, and automatically select the rework time and the spray pipe arm swing program based on the distribution of the photoresist residue area and the amount of photoresist residue. Because abnormal substrates are directly reworked online, no manual identification is required, and the rework conditions (rework time, spray pipe arm swing program) are determined by the photoresist residue area and amount of the substrate, the rework time of abnormal substrates can be accurately controlled, thereby improving rework efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 Shown is a process flow chart of the photoresist removal method of the present invention.

[0044] Figure 2 The schematic diagram shows a substrate sheet including an inner circle area, a middle circle area, and an outer circle area sequentially distributed from the center of the substrate sheet to the edge of the substrate sheet.

[0045] Figure 3 The diagram shows 49 measurement points distributed in the inner, middle, and outer areas of the substrate.

[0046] Component number description

[0047] 100 Inner Circle Area

[0048] 200 Central Area

[0049] 300 outer area DETAILED DESCRIPTION

[0050] The following describes the embodiments of the present invention through specific examples. Those skilled in the art will readily understand the other advantages and benefits of the present invention from the disclosure herein. The present invention may also be implemented or applied through various other specific embodiments, and the details in this specification may be modified or altered based on different viewpoints and applications without departing from the spirit of the present invention.

[0051] See also Figures 1 to 3 It should be noted that the diagrams provided in this embodiment are merely schematic illustrations of the basic concept of the present invention. Therefore, the diagrams only show components related to the present invention and are not drawn according to the number, shape, and size of components in actual implementation. In actual implementation, the type, quantity, and proportion of each component may be changed arbitrarily, and the component layout may also be more complex.

[0052] Example 1

[0053] This embodiment provides a method for removing photoresist. Figure 1 , shown as a process flow diagram of the method, comprising the following steps:

[0054] Wet stripping step: using a substrate conveying device to convey the substrate into a wet stripping chamber to remove the photoresist on the surface of the substrate;

[0055] Defect detection step: using a defect detection device to detect the total amount of photoresist residue on the surface of the substrate, if the total amount of photoresist residue is lower than a preset value, then performing a wet stripping step and a defect detection step for the next substrate; if the total amount of photoresist residue is higher than the preset value, then performing a stripping rework step and repeating the defect detection step;

[0056] The debonding and rework step includes: using the substrate conveying device to convey the substrate to the wet debonding chamber again to remove the photoresist remaining on the surface of the substrate.

[0057] As an example, the time required for photoresist stripping and rework is automatically calculated based on the photoresist residue of an abnormal substrate (a substrate with a total photoresist residue higher than a preset value), and the rework is completed.

[0058] As an example, the wet stripping machine used in the photoresist removal method of this embodiment includes a wet stripping chamber, a defect detection device and a substrate conveying device, wherein the wet stripping chamber is responsible for completing the wet stripping process, the defect detection device can adopt a defect scanner, which is responsible for scanning and taking pictures of the photoresist residues and calculating the residual thickness according to the refractive index of the light source, and the substrate conveying device is responsible for the operation of the substrate between each module.

[0059] The technical solution of this embodiment is described below using a batch of 25 substrates as an example.

[0060] Step 1: The first substrate is subjected to a stripping process in the wet stripping chamber using a mass production process, and then returned to the defect detection device for photoresist residue scanning. If the result is normal (the total amount of photoresist residue is lower than a preset value), the second substrate is stripped (see step 4 below); if the result is abnormal (the total amount of photoresist residue is higher than a preset value), the defect detection device automatically takes a photo of the substrate, measures the size of each residual area based on the photographed photo, and calculates the area of each residual area and the residual photoresist thickness at the center of the corresponding residual area, where the area of the nth residual area is S n , the thickness of the residual photoresist at the center of the nth residual area is H n , n is an integer, and n ≥ 0, and then automatically calculate the total photoresist residue P, where P = S1*H1+S2*H2+…+S n *H n .

[0061] As an example, the size of the nth residual region includes the length L n and width W n , the area S of the nth residual region n =L n *W n .

[0062] As an example, the residual photoresist thickness is calculated based on the refractive index of the light source, which is well known to those skilled in the art and will not be described in detail here.

[0063] Step 2: The abnormal substrate is transferred to the wet stripping chamber again by the substrate transfer device. The system automatically calculates the time required for the substrate to be stripped and reworked, and performs the stripping and rework step based on the time required for the stripping and rework.

[0064] As an example, the time required for the stripping rework is t=P / {(S1+S2+...+S n )*V}, where P is the total amount of photoresist residue, S nis the area of the nth residual area, V is the average rate of adhesive stripping per unit area, n is an integer, and n ≥ 0. Based on the time required for the adhesive stripping rework, the adhesive stripping liquid is supplied to the entire surface of the substrate to perform the adhesive stripping rework step. In this embodiment, the average rate of adhesive stripping per unit area V is obtained based on daily monitoring data.

[0065] As an example, obtaining the average adhesive removal rate V per unit area based on daily monitoring data includes the following steps:

[0066] (1) Measure the photoresist thickness of a test substrate, and refer to the measured value as the previous value.

[0067] As an example, the number of measurement points is 49, which are denoted as a1, a2, ..., a49. Of course, in other embodiments, the number and distribution of measurement points can also be adjusted as needed, which should not unduly limit the scope of protection of the present invention.

[0068] (2) The experimental substrate is sent into the wet debonding chamber for partial debonding, and the debonding time is recorded as T.

[0069] (3) Measure the photoresist thickness of the experimental substrate after stripping again, and refer to the measured value as the post-value, which is recorded as b1, b2, ..., b 49 .

[0070] (4) Calculate the average rate of debonding per unit area of the experimental substrate, denoted as V. Where:

[0071] V={(a1-b1)+(a2-b2)+...+(a 49 -b 49 )} / 49 / T.

[0072] Step 3: After rework, the substrate is returned to the defect detection device for photoresist residue scanning. If the result is normal, proceed to step 4; if there is still residue, rework and inspection are performed according to steps 2 and 3 until the substrate meets the requirements.

[0073] Step 4: The second substrate piece is subjected to the debonding process in the wet debonding chamber using the mass production procedure, and is returned to the defect detection device for photoresist residue scanning. If the result is normal, the debonding process for the third substrate piece is carried out; if there is residue, the second and third steps are followed for rework and inspection until the substrate piece meets the requirements.

[0074] By analogy, the system completes the wet stripping process of 25 substrates and automatically detects and reworks them. Of course, in other embodiments, the number of substrates in a batch can be adjusted as needed, and this should not overly limit the scope of protection of the present invention.

[0075] The photoresist removal method of this embodiment can detect the presence of photoresist residue on substrates online, automatically measure the size of the residual photoresist area, calculate the residual area and thickness, and automatically estimate the time required for photoresist removal rework based on the amount of photoresist residue on abnormal substrates, thereby completing the rework. Because abnormal substrates are directly reworked online without manual identification, and the rework conditions are determined by the amount of photoresist residue on the substrates, the rework time for abnormal substrates can be precisely controlled, improving rework efficiency.

[0076] Example 2

[0077] This embodiment adopts basically the same technical solution as the first embodiment, except that, in the degumming and rework step, the first embodiment supplies degumming liquid to the entire substrate surface, while the present embodiment supplies degumming liquid based on the distribution of the photoresist residual area.

[0078] As an example, the swing arm area of the arm (liquid spraying pipe) containing the degumming liquid is automatically calculated based on the abnormal photoresist residual area of the substrate, and the rework is completed.

[0079] As an example, the substrate sheet includes at least two areas arranged in sequence from the center of the substrate sheet to the edge of the substrate sheet. When the photoresist residue area is only distributed in one of the areas, in the degumming and rework step, the degumming liquid supply arm only swings back and forth between the inner edge and the outer edge of the area with photoresist residue; when the photoresist residue area is distributed in at least two areas, the degumming liquid supply arm swings back and forth between the inner edge of the innermost area with photoresist residue and the outer edge of the outermost area with photoresist residue.

[0080] As an example, Figure 2 As shown, the substrate sheet includes an inner circle area 100, a middle circle area 200 and an outer circle area 300 distributed in sequence from the center of the substrate sheet to the edge of the substrate sheet, wherein the inner edge of the inner circle area 100 is the center of the substrate sheet, and the distance between the outer edge of the inner circle area 100 and the center of the substrate sheet is one-third of the radius of the substrate sheet; the inner edge of the middle circle area 200 coincides with the outer edge of the inner circle area 100, and the distance between the outer edge of the middle circle area 200 and the center of the substrate sheet is two-thirds of the radius of the substrate sheet; the inner edge of the outer circle area 300 coincides with the outer edge of the middle circle area 200, and the outer edge of the outer circle area 300 is the outer edge of the substrate sheet.

[0081] The technical solution of this embodiment is described below using a batch of 25 substrates as an example.

[0082] Step 1: The first substrate is stripped in the wet stripping chamber using the mass production process. The substrate is then returned to the defect detection device for photoresist residue scanning. If the result is normal, the second substrate is stripped. If there is any residue, the system automatically records the residue areas A1, A2, A3, ..., A n .

[0083] Step 2: The abnormal substrate is transferred to the wet debonding chamber again by the substrate conveyor. The system selects the corresponding swing arm program according to the residual area distribution and completes the debonding process. The swing arm program corresponds to the following:

[0084] a) The residual area is only distributed in the inner circle area, and the arm containing the debonding liquid swings from the center of the substrate to the outer edge of the inner circle and swings back and forth;

[0085] b) The residual area is only distributed in the middle circle area, and the arm containing the debonding liquid swings from the outer edge of the inner circle of the substrate to the outer edge of the middle circle and swings back and forth;

[0086] c) The residual area is only distributed in the outer circle area, and the arm containing the debonding liquid swings from the outer edge of the middle circle of the substrate to the outer edge of the outer circle and swings back and forth;

[0087] d) The residual area is distributed in both the inner and middle circle areas, and the arm containing the debonding liquid swings from the center of the substrate to the outer edge of the middle circle and swings back and forth;

[0088] e) The residual area is distributed in both the inner and outer ring areas, and the arm containing the debonding liquid swings from the center of the substrate to the outer edge of the outer ring and swings back and forth;

[0089] f) The residual area is distributed in the middle circle area and the outer circle area at the same time, and the arm containing the debonding liquid swings from the outer edge of the inner circle of the substrate to the outer edge of the outer circle and swings back and forth;

[0090] g) The residual areas are distributed in the inner circle, the middle circle and the outer circle at the same time, and the arm containing the debonding liquid swings from the center of the substrate to the outer edge of the outer circle and swings back and forth.

[0091] It should be pointed out that in this step, the system can automatically calculate the time required for the degumming and rework of the substrate piece as in the second step of Example 1, and perform the degumming and rework step based on the time required for the degumming and rework. The method for calculating the time required for the degumming and rework can be found in Example 1 and will not be repeated here.

[0092] Step 3: After rework, the substrate is returned to the defect detection device for photoresist residue scanning. If the result is normal, proceed to step 4; if there is still residue, rework and inspection are performed according to steps 2 and 3 until the substrate meets the requirements.

[0093] Step 4: The second substrate piece is subjected to the debonding process in the wet debonding chamber using the mass production procedure, and is returned to the defect detection device for photoresist residue scanning. If the result is normal, the debonding process for the third substrate piece is carried out; if there is residue, the second and third steps are followed for rework and inspection until the substrate piece meets the requirements.

[0094] Similarly, the system completes the wet stripping process for 25 substrates and automatically inspects and reworks them.

[0095] The photoresist removal method of this embodiment can detect online whether there is photoresist residue on a substrate, automatically measure the size of the photoresist residue area, calculate the residual area and thickness of the photoresist residue, and automatically estimate the time required for photoresist removal rework based on the amount of photoresist residue on the abnormal substrate. It can also automatically select the liquid spray arm swing program based on the distribution of the photoresist residue area and complete the rework. Because abnormal substrates are directly reworked online, no manual distinction is required, and the rework time is determined by the amount of photoresist residue on the substrate, and the arm swing program containing the liquid spray is determined by the distribution of the photoresist residue area on the substrate, the rework time of abnormal substrates can be precisely controlled, improving rework efficiency.

[0096] Example 3

[0097] This embodiment and the second embodiment adopt basically the same technical solution, the difference being that, in the degumming and rework step, the second embodiment supplies degumming liquid based on the distribution of the photoresist residual area, and automatically calculates the time required for degumming and rework of the substrate based on the total photoresist residual amount of the substrate, while this embodiment not only supplies degumming liquid based on the distribution of the photoresist residual area, but also calculates the time required for degumming and rework of the substrate based on the distribution of the photoresist residual area.

[0098] As an example, the rework time of the abnormal substrate and the swing program of the liquid spray pipe are automatically calculated based on the photoresist residue amount and residue area of the abnormal substrate, and the rework is completed.

[0099] As an example, the time required for the stripping and rework of the substrate piece is calculated based on the distribution of the photoresist residual area by the following method: the time required for the stripping and rework of different areas of the substrate piece is calculated, and the time required for the stripping and rework of the area with the longest stripping and rework time is taken as the stripping and rework time of the substrate piece.

[0100] As an example, calculating the time required for the debonding rework of different areas of the substrate includes the following steps:

[0101] (1) providing an experimental substrate, and measuring the thickness of the photoresist at m points in the i-th region of the experimental substrate, wherein i is an integer greater than 0, and m is an integer greater than 1;

[0102] In this embodiment, the residual photoresist thickness is calculated based on the refractive index of the light source.

[0103] (2) placing the experimental substrate into the wet stripping chamber for a preset time T to remove a portion of the photoresist on the surface of the experimental substrate;

[0104] (3) measuring the thickness of the photoresist at the m points in the i-th area of the experimental substrate again;

[0105] (4) superimposing the photoresist thickness changes before and after photoresist stripping at the m points in the i-th region of the experimental substrate, and dividing the sum by m and T to obtain an average photoresist stripping rate for the i-th region of the experimental substrate;

[0106] (5) In the defect detection step, the defect detection device is used to detect the total amount of photoresist residue in the i-th area of the substrate, and the total amount of photoresist residue in the i-th area of the substrate is divided by the total photoresist residue area of the i-th area of the substrate and the average debonding rate of the i-th area of the experimental substrate to obtain the time required for debonding rework of the i-th area of the substrate.

[0107] As an example, using the defect detection device to detect the total amount of photoresist residue in the i-th area of the substrate includes the following steps:

[0108] 1. Taking a photo of the substrate;

[0109] II. Measure the size of each residual region in the i-th region of the substrate based on the photographed photo and calculate the area of each residual region and the residual photoresist thickness at the center of the corresponding residual region, where the area of the n-th residual region is S n , the thickness of the residual photoresist at the center of the nth residual area is H n , n is an integer, and n≥0;

[0110] As an example, the size of the nth residual region includes the length L n and width W n , the area S of the nth residual region n =L n *W n .

[0111] III. Calculate the total amount of photoresist residue P in the i-th area of the substrate, where P = S1*H1+S2*H2+…+S n *H n .

[0112] The technical solution of this embodiment is described below using a batch of 25 substrates as an example.

[0113] Step 1: Measure the photoresist thickness of a piece of experimental substrate, and the measured value is called the previous value.

[0114] As an example, the number of measurement points is 49, which are denoted as a1, a2, ..., a49. Figure 3 As shown, the 49 points are distributed in the inner, middle, and outer regions of the substrate. The division rules for the inner, middle, and outer regions can be found in Example 2 and will not be repeated here. Of course, in other embodiments, the number of measurement points and the division of regions can be adjusted as needed, and this should not unduly limit the scope of protection of the present invention.

[0115] Step 2: The experimental substrate is placed into the wet debonding chamber for partial debonding, and the debonding time is recorded as T.

[0116] Step 3: Measure the photoresist thickness of the experimental substrate again after stripping, and the measured value is called the post-value, recorded as b1, b2, ..., b 49 .

[0117] Step 4: Calculate the average debonding rate of the inner, middle, and outer regions of the experimental substrate, and record it as V A , V B , V C .in:

[0118] V A ={(a1-b1)+(a2-b2)+...+(a9-b9)} / 9 / T;

[0119] V B ={(a 10 -b 10 )+(a 11 -b 11 )+...+(a 25 -b 25 )} / 16 / T;

[0120] V C ={(a 26 -b 26 )+(a 27 -b 27 )+...+(a 49 -b 49 )} / 24 / T.

[0121] Step 5: The first substrate is stripped in the wet stripping chamber using the mass production process, and then returned to the defect detection device for photoresist residue scanning. If the result is normal, the second substrate is stripped. If there is residue, the defect detection device automatically takes a photo, measures the length L and width W of each residue area, automatically records the residue area, and determines the distribution area of the residue area on the substrate (inner circle, middle circle, outer circle), and the inner circle is recorded as A1, A2, A3, ..., A n , the middle circle is marked as B1, B2, B3, ..., B n , the outer circle is marked as C1, C2, C3, ..., C n The system automatically calculates the area of each area (length L*width W), and the inner circle is counted as S A1 , S A2 ,...,S An , the middle circle is counted as S B1 , S B2 ,...,S Bn , the outer ring is counted as S C1 , S C2 ,...,S Cn , and the thickness of the residual glue in the center of the corresponding area, the inner circle is counted as H A1 , H A2 ,...,H An , the middle circle is counted as H B1 , H B2 ,...,H Bn , the outer ring is counted as H C1 , H C2 ,...,H Cn The system automatically calculates the total amount of photoresist residue in each circle, and the inner circle is recorded as P A =S A1 *H A1 +S A2 *H A2 +...+S An *H An , the middle circle is marked as P B =S B1 *H B1 +S B2 *H B2 +...+S Bn *H Bn , the outer circle is recorded as PC=S C1 *H C1 +S C2 *H C2 +...+S Cn *H Cn .

[0122] Step 6: The abnormal substrate is transferred to the wet stripping chamber again by the substrate conveyor. The system selects the rework time and arm swing program based on the amount of photoresist residue and the residual area and completes the stripping process. The process time and arm swing program selection logic is as follows:

[0123] a) The residual area is only distributed in the inner circle area: the time required for degumming and rework is t = P A / (S A *V A )=(S A1 *H A1 +S A2 *H A2 +...+S An *H An ) / {(S A1 +S A2 +...+S An )*(a1-b1+a2-b2+...+a9-b9) / 9 / T}, the arm containing the debonding liquid swings from the center of the substrate to the outer edge of the inner circle and swings back and forth;

[0124] b) The residual area is only distributed in the middle circle area: the time required for debonding and rework is t = P B / (S B *V B )=(S B1 *H B1 +S B2 *H B2 +...+S Bn *H Bn ) / {(S B1 +S B2 +...+S Bn )*(a 10 -b 10 +a 11 -b 11 +...+a 25 -b 25 ) / 16 / T}, the arm containing the debonding liquid swings from the outer edge of the inner circle of the substrate to the outer edge of the middle circle and swings back and forth;

[0125] c) The residual area is only distributed in the outer area: the time required for degumming and rework is t = P C / (S C *V C )=(S C1 *H C1 +S C2 *H C2 +...+S Cn *H Cn ) / {(S C1 +S C2 +...+SCn )*(a 26 -b 26 +a 27 -b 27 +...+a 49 -b 49 ) / 24 / T}, the arm containing the debonding liquid swings from the outer edge of the middle circle of the substrate to the outer edge of the outer circle and swings back and forth;

[0126] d) The residual area is distributed in the inner and middle areas at the same time: the time required for degumming and rework is t=max(P A / (S A *V A ), P B / (S B *V B )), the arm containing the debonding liquid swings from the center of the substrate to the outer edge of the middle circle and swings back and forth, where max means taking the maximum value;

[0127] e) The residual area is distributed in both the inner and outer areas: the time required for degumming and rework is t=max(P A / (S A *V A ), P C / (S C *V C )), the arm containing the debonding liquid swings from the center of the substrate to the outer edge of the outer circle and swings back and forth;

[0128] f) The residual area is distributed in the middle and outer areas at the same time: the time required for degumming and rework is t=max(P B / (S B *V B ), P C / (S C *V C )), the arm containing the debonding liquid swings from the outer edge of the inner circle of the substrate to the outer edge of the outer circle and swings back and forth;

[0129] g) The residual area is distributed in the inner circle, middle circle and outer circle at the same time. The time required for de-glueing and rework is t=max(P A / (S A *V A ), P B / (S B *V B ), P C / (S C *V C )), the arm containing the debonding liquid swings from the center of the substrate to the outer edge of the outer circle and swings back and forth.

[0130] Step 7: After rework, the substrate is returned to the defect detection device for photoresist residue scanning. If the result is normal, proceed to step 8; if there is still residue, rework and inspection are performed according to steps 5 and 6 until the substrate meets the requirements.

[0131] Step 8: The second substrate piece is subjected to the debonding process in the wet debonding chamber using the mass production procedure, and is returned to the defect detection device for photoresist residue scanning. If the result is normal, the debonding process for the third substrate piece is carried out; if there is residue, the process is reworked and inspected according to steps 5 and 6 until the substrate piece meets the requirements.

[0132] Similarly, the system completes the wet stripping process for 25 substrates and automatically inspects and reworks them.

[0133] The photoresist removal method of this embodiment can detect the presence of photoresist residue on a substrate online, automatically measure the size of the residual photoresist area, calculate the residual area and thickness, and automatically select the rework time and spray arm swing program based on the distribution of the residual photoresist area and the amount of residual photoresist. Because abnormal substrates are directly reworked online, no manual identification is required, and the rework conditions (rework time and spray arm swing program containing the adhesive stripping solution) are determined by the residual photoresist area and amount on the substrate, the rework time of abnormal substrates can be precisely controlled, improving rework efficiency.

[0134] Example 4

[0135] In this embodiment, a photoresist removal device is provided, including a substrate conveying device, a wet stripping chamber and a defect detection device, wherein the substrate conveying device is used to convey substrates, the wet stripping chamber is used to remove photoresist on the surface of the substrate, and the defect detection device is used to detect the total amount of photoresist residue on the surface of the substrate and compare the total amount of photoresist residue with a preset value. If the total amount of photoresist residue is lower than the preset value, the substrate conveying device is controlled by a control module connected to the defect detection device, the wet stripping chamber and the substrate conveying device to convey the next substrate to the wet stripping chamber; if the total amount of photoresist residue is higher than the preset value, the substrate conveying device is controlled by the control module to convey the substrate to the wet stripping chamber again for a stripping rework step, and after the stripping rework, the substrate is conveyed to the defect detection device again for photoresist residue detection.

[0136] As an example, the defect detection device also includes a camera module connected to the control module for taking pictures of the substrate, a size measurement module for measuring the size of each residual area and calculating the area of the residual area, and a thickness measurement module for measuring the thickness of the residual photoresist.

[0137] As an example, the control module is further configured to calculate a time required for debonding and reworking the substrate piece, and control a debonding and reworking time of the substrate piece in the wet debonding chamber based on the time required for debonding and reworking.

[0138] As an example, the time required for the stripping rework is t=P / {(S1+S2+...+S n )*V}, where P is the total amount of photoresist residue, S n is the area of the nth residual area, V is the average rate of debonding per unit area, n is an integer, and n≥0.

[0139] As an example, the wet stripping chamber further includes a stripping liquid supply arm, and the control module is further configured to control the stripping liquid supply arm to supply the stripping liquid to a preset area of the substrate based on the distribution of the photoresist residue area.

[0140] As an example, the control module is also used to calculate the time required for the substrate stripping rework based on the distribution of the photoresist residual area, and control the stripping rework time of the substrate in the wet stripping chamber based on the time required for the stripping rework.

[0141] The photoresist device of this embodiment can detect online whether there is photoresist residue on the substrate, automatically measure the size of the photoresist residue area, calculate the residue area and the photoresist residue thickness, and automatically select the rework time and the spray pipe swing arm program according to the distribution of the photoresist residue area and the residual amount of photoresist.

[0142] In summary, the photoresist removal method and device of the present invention can detect online whether there is photoresist residue on a substrate, automatically measure the size of the photoresist residue area, calculate the residual area and photoresist residue thickness, and automatically select the rework time and the spray pipe arm swing program based on the distribution of the photoresist residue area and the amount of photoresist residue. Because abnormal substrates are directly reworked online, no manual distinction is required, and the rework conditions (rework time, spray pipe arm swing program) are determined by the photoresist residue area and the amount of residue on the substrate, the rework time of abnormal substrates can be accurately controlled, thereby improving rework efficiency.

[0143] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the present invention. Anyone skilled in the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by one of ordinary skill in the art without departing from the spirit and technical principles disclosed herein are intended to be covered by the claims of the present invention.

Claims

1. A method for removing photoresist, characterized in that: The following steps are involved: Wet stripping step: using a substrate conveying device to convey the substrate into a wet stripping chamber to remove the photoresist on the surface of the substrate; Defect detection step: using a defect detection device to detect the total amount of photoresist residue on the surface of the substrate, if the total amount of photoresist residue is lower than a preset value, then proceeding to the wet stripping step and defect detection step of the next substrate; If the total amount of photoresist residue is higher than the preset value, a photoresist stripping and reworking step is performed, and the defect detection step is repeated; Steps for calculating the time required for photoresist stripping and rework: Calculate the time required for photoresist stripping and rework based on the amount of photoresist residue or the distribution of the photoresist residue area; Among them, the degumming and rework step includes: using the substrate sheet conveying device to convey the substrate sheet to the wet degumming chamber again, and controlling the degumming and rework time of the substrate sheet in the wet degumming chamber based on the time required for the degumming and rework to remove the photoresist remaining on the surface of the substrate sheet.

2. The photoresist removal method according to claim 1, wherein: The defect detection device detects the total amount of photoresist residue and comprises the following steps: Taking a photo of the substrate; Based on the photographed photos, the size of each residual region is measured and the area of each residual region and the residual photoresist thickness at the center of the corresponding residual region are calculated, where the area of the nth residual region is S n , the thickness of the residual photoresist at the center of the nth residual area is H n , n is an integer, and n≥0; Calculate the total photoresist residue P, where P = S1*H1+S2*H2+…+S n *H n .

3. The photoresist removal method according to claim 1, wherein: The time required for the desizing and rework is t=P / {(S1+S2+...+S n )*V}, where P is the total amount of photoresist residue, S n is the area of the nth residual area, V is the average rate of debonding per unit area, n is an integer, and n≥0.

4. The photoresist removal method according to claim 1, wherein: In the stripping and rework step, a stripping solution is supplied based on the distribution of the photoresist residual area.

5. The photoresist removal method according to claim 4, wherein: The substrate sheet includes at least two areas arranged in sequence from the center of the substrate sheet to the edge of the substrate sheet. When the photoresist residue area is only distributed in one of the areas, in the degumming and rework step, the degumming liquid supply arm only swings back and forth between the inner edge and the outer edge of the area with photoresist residue; when the photoresist residue area is distributed in at least two areas, the degumming liquid supply arm swings back and forth between the inner edge of the innermost area with photoresist residue and the outer edge of the outermost area with photoresist residue.

6. The photoresist removal method according to claim 4, wherein: The substrate sheet includes an inner circle area, a middle circle area, and an outer circle area distributed in sequence from the center of the substrate sheet to the edge of the substrate sheet, wherein the inner edge of the inner circle area is the center of the substrate sheet, and the distance between the outer edge of the inner circle area and the center of the substrate sheet is one-third of the radius of the substrate sheet; the inner edge of the middle circle area coincides with the outer edge of the inner circle area, and the distance between the outer edge of the middle circle area and the center of the substrate sheet is two-thirds of the radius of the substrate sheet; the inner edge of the outer circle area coincides with the outer edge of the middle circle area, and the outer edge of the outer circle area is the outer edge of the substrate sheet.

7. The photoresist removal method according to any one of claims 4 to 6, wherein: Calculating the time required for the stripping and rework of the substrate based on the distribution of the photoresist residual area includes: calculating the time required for the stripping and rework of different areas of the substrate, and taking the time required for the stripping and rework of the area with the longest stripping and rework time as the stripping and rework time of the substrate.

8. The photoresist removal method according to claim 7, wherein: Calculating the time required for debonding and reworking different areas of the substrate comprises the following steps: Providing an experimental substrate, measuring the thickness of the photoresist at m points in an i-th region of the experimental substrate, wherein i is an integer greater than 0 and m is an integer greater than 1; Placing the experimental substrate into the wet stripping chamber for a preset time T to remove a portion of the photoresist on the surface of the experimental substrate; again measuring the thickness of the photoresist at the m points in the i-th region of the experimental substrate; Adding the photoresist thickness changes before and after photoresist stripping at the m points in the i-th region of the experimental substrate and dividing the sum by m and T to obtain an average photoresist stripping rate for the i-th region of the experimental substrate; In the defect detection step, the defect detection device is used to detect the total amount of photoresist residue in the i-th area of the substrate, and the total amount of photoresist residue in the i-th area of the substrate is divided by the total photoresist residue area of the i-th area of the substrate and the average debonding rate of the i-th area of the experimental substrate to obtain the time required for debonding rework of the i-th area of the substrate.

9. The photoresist removal method according to claim 8, wherein: Using the defect detection device to detect the total amount of photoresist residue in the i-th area of the substrate comprises the following steps: Taking a photo of the substrate; Based on the photographed photos, the size of each residual region in the i-th region of the substrate is measured and the area of each residual region and the residual photoresist thickness at the center of the corresponding residual region are calculated, where the area of the n-th residual region is S n , the thickness of the residual photoresist at the center of the nth residual area is H n , n is an integer, and n≥0; Calculate the total photoresist residue P in the i-th area of the substrate, where P = S1*H1+S2*H2+…+S n *H n .

10. A photoresist removal device, characterized in that: include: A substrate sheet conveying device, used for conveying substrate sheets; Wet stripping chamber, used to remove photoresist from the surface of the substrate; a defect detection device for detecting a total amount of photoresist residue on the surface of the substrate and comparing the total amount of photoresist residue with a preset value; if the total amount of photoresist residue is lower than the preset value, controlling the substrate conveying device to convey the next substrate to the wet stripping chamber via a control module connected to the defect detection device, the wet stripping chamber, and the substrate conveying device; If the total amount of photoresist residue is higher than a preset value, the control module controls the substrate conveying device to convey the substrate to the wet stripping chamber again for a stripping rework step, and after the stripping rework, convey the substrate to the defect detection device again for photoresist residue detection; The control module is further configured to calculate the time required for the substrate stripping and reworking based on the amount of photoresist residue or the photoresist residue area, and to control the substrate stripping and reworking time in the wet stripping chamber based on the time required for the stripping and reworking.

11. The photoresist removal device according to claim 10, wherein: The defect detection device also includes a camera module connected to the control module for taking pictures of the substrate, a size measurement module for measuring the size of each residual area and calculating the area of the residual area, and a thickness measurement module for measuring the thickness of the residual photoresist.

12. The photoresist removal device according to claim 10, wherein: The time required for the desizing and rework is t=P / {(S1+S2+...+S n )*V}, where P is the total amount of photoresist residue, S n is the area of the nth residual area, V is the average rate of debonding per unit area, n is an integer, and n≥0.

13. The photoresist removal device according to claim 10, wherein: The wet stripping chamber further includes a stripping liquid supply arm, and the control module is further configured to control the stripping liquid supply arm to supply the stripping liquid to a preset area of the substrate based on the distribution of the photoresist residue area.

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