TW540126B - Method of monitoring edge bevel rinse and wafer edge exposure - Google Patents

Abstract

A wafer comprising a plurality of marks positioned at a first distance from the center of the wafer is provided. A photoresist layer is coated on a surface of the wafer. An edge bevel rinse (EBR) device is provided to rinse the photoresist layer and form a photoresist pattern in a circular shape, an outer edge of the circular photoresist pattern keeping at least a second distance from the center of the wafer. A baking process, an exposure process, and a development process are performed to the wafer. An after-development-inspection (ADI) process is performed to measure a difference between the first distance and the second distance.

Description

540126 V. Description of the invention (1) Field of the invention The present invention provides a method for detecting abnormalities of edge bevel rinse (EBR) and wafer edge exposure (wafer edge exposure (ffEE)), thereby monitoring a robot arm ( main arm). Background note Almost all chances of infection are used to detect and some containment systems. It is sent to the wafer to break. It is used to say that if the large transmission system is detected, there will be no errors. The conductor process is automated. Based on the equipment included in this device, the wafers used to detect the loading wafers as robotic wafers in the crystal transfer system are set to ensure that the difference of 0 degrees is avoided to avoid the positioning of the crystal arms (ma i η The measured circle transmission is the required degree of instruction and the signal processing equipment is taken into consideration because of the equipment. The circle detection of the wafer wafer is placed, and then the wafer in the arm itself is cleanly transmitted. The correct robotic device of the guide detects the sensitive positioning through the movement of the crystal, and transmits it to the signal of the chip, which is set to the circle detection arm. Due to the requirements, there are some devices that are transmitted to the subsequent transmission wafer contamination. The wafer transmission will be counted and judged. It is reasonable to correctly position the wafer transmission. ::: But it is easy because of all kinds of wafers. Transmission system factors, which affect the factors such as crystal Π ::, ϋ: poor, and parts loss-? Positioning after transmission to process equipment. When the chip is passed

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V. Description of the invention (2) When the positioning is not correct after input to the process equipment, it often affects the correctness of the structure after completion. Because in the precise semiconductor manufacturing process, not only the relative position of each layer structure and the upper and lower structure is extremely important, but also the relative positions of different components in the same layer and junction are very important, so incorrect positioning will cause The problem, especially in the definition of the structure shape: the position of the photolithography process, the problem of this incorrect positioning is even more direct. In addition, if any “inaccurate positioning or moving displacement” occurs during the process of conveying and transferring the wafer, it is more likely to affect the subsequent process and even cause the wafer to be damaged. Taking the conventional yellow light process as an example, The photo-resistance covering development (track) machine equipped with multiple robotic arms often has to be arranged with preventive maintenance (PM) at a fixed frequency to avoid quality problems due to inaccurate positioning ·. However, procedures such as check and calibration in preventive maintenance take considerable time, and the equipment must be down, which severely affects production capacity. Please refer to Figure 1, which is a flowchart 30 of the conventional Huangguang process. As shown in FIG. 1, at least one semiconductor wafer having completed structure (not shown) is first provided (step 10). The size of the semiconductor wafer may be 200 mm or 300 mm. Next, the semiconductor wafer is transferred to a uniform (i η 1 ine) photoresist-covering developing machine using a robot arm (step 12), and then a spin-on is performed on a spin-on coating platform. ) Process (step 14) to

Page 7 540126 V. Description of the invention (3) A photoresist layer is formed on the semiconductor wafer. Next, a cleaning process called edge bevel rinse (EBR) is performed (step 16). Please refer to FIG. 2, which is a schematic diagram of a crystal edge cleaning process (step 16). As shown in Figure 2, the crystal edge cleaning process is to first locate the nozzle 5 (^ at a standby position 52, the waiting position 52 is located outside the projection position 55 directly above the semiconductor wafer 54, and then The semiconductor wafer 54 rotates at a constant speed and moves the nozzle 50 back and forth between a position A and a position 58. Among them, the position A is also located at the projection position 5 directly above the semiconductor wafer 54. The area other than 5 is located at position B. 5 is located directly above the semiconductor wafer 5 4 at the area within projection position 5 5. The nozzle 50 is moved from the position A to the position 57 through the edge of the semiconductor wafer 54 to the position B. Then, it moves to the A position 56 by the edge projection position 57 of the semiconductor wafer. The distance d between the edge projection position 57 of the semiconductor wafer and the B position 58 is the range of crystal edge cleaning, and the nozzle 5 It is at an angle of about 45 degrees with the surface of the semiconductor wafer 54. Then, the semiconductor wafer is transported onto a thermal pad (1107 & 16) by another robot arm for a hard roasting (^ & 1 ^ 1 ^] ^) process (step Step 18). The purpose of the hard baking process is to remove the solvent in the photoresist layer from the photoresist layer, so that the photoresist layer is changed from the original liquid state into a thin film of the state, and the photoresist layer is aligned with the wafer. Surface adhesion (adhesi capability is enhanced to facilitate subsequent processes. After completion, an exposure process (exposure, step 20) and a development process (developerment, step

540126 V. Description of the invention (4) Two to two? A desired pattern is formed in the resist layer. Finally, perform-display: big step 24) to determine the size ... location of the pattern formed in the photoresist layer. Of course, for hard-boiled wafers. The purpose of the crystal edge cleaning to the dagger 3 is to clean the photoresist layer of about 1.5 mm in the edge of the semiconductor wafer. Adding this process can effectively prevent the machine from being contaminated by the liquid photoresist when the conductor wafer is transported to the thermal pad after completion. In addition, in other post-production processes (even non-yellow light processes), it is often necessary to use the arm to pinch the spine! ^ Need to use a mechanical barrier with a claw (clamp) to scratch ==, the claw is easy to The optical layer on the edge of the semiconductor wafer was scratched, so that particles were generated, and the crystal edge cleaning process was added. This problem was also solved. ', — The conductor yellow light process is facing a problem. In order to ensure half =; said two: the correct positioning of Fenghua's neck adjustment robot arm when transmitting to each (process unit), and adjust several times at a time. The loss of production capacity of two robotic arms. To solve this problem, the monitoring method at 2 o’clock is based on the yellow light process r to avoid J: the exact position of 1 is sent to achieve the warning effect.

Moon Dagger avoids too frequent adjustments. T invention overview

540126

Therefore, the method of the "main arm" of the present invention should be adopted to solve the above problems. The purpose of the invention is to provide a monitoring robot arm which is used in a photoresist-covered developing machine in a preferred embodiment. The present invention uses a method to detect the sun and the sun's edge > edge bevel rinse (EBR) and crystal edges An abnormal method of wafer exposure (WEE) to monitor the transmission accuracy of the main arm. First, a wafer is provided, and the wafer includes a plurality of symmetrical marks that are at a first distance from the center of the wafer. The wafer surface is then coated with a photoresist layer and then cleaned with a crystal edge ( edge bevel rinse (EBR) device to clean the photoresist layer to form a circular photoresist layer pattern on the wafer, and make the outer edges of the circular photoresist layer pattern (〇uteredge) away from the wafer. The center of the circle is at least a second distance, and finally the wafer is subjected to processes such as baking, exposure, and development, and a post-development inspection step is performed to measure a difference between the first distance and each of the first and first distances. The main feature of the present invention is to use a wafer with a mark to perform the crystal edge cleaning process after photoresist coating. In this way, not only can the wafer be judged by the relative position of the mark and the remaining photoresist layer. Whether the positioning is wrong, and then confirm the transmission accuracy of the robotic arm, to save time spent unnecessary adjustment. At the same time, a method of re-checking I (doub 1 e check) can be provided to prevent the inspection steps after development from being performed incorrectly. If the check is not performed immediately, a large number of products continue to be manufactured, causing serious problems.

540126

At the same time, the robot arm was contaminated by particles (particles) on the edge of the wafer and semiconductor wafer during the liquid photoresist process (even non-yellow process). At the same time, the claws (clamps) of other subsequent robotic arms are prevented from scratching the control layer, so that after the generation of particles two, the other robotic hand f is used to transport the control sheet α and the semiconductor wafer ^ a hot plate To perform a hard baking process (step 108). The purpose of the hard baking process is to remove the solvent (sol verity) from the photoresist layer in the photoresist layer, so that the photoresist layer is changed from the original liquid state to The solid-state film enhances the adhesion of the photoresist layer to the wafer surface to facilitate subsequent processes. After completion, an exposure process (expOsure, step 11) and a development process are sequentially performed. (Step 112) to form a desired pattern in the photoresist layer. Finally, a post-development inspection (ADI, step 114) is performed to determine that the size and position of the pattern formed in the photoresist layer are correct. For post-inspection, you can check or measure different purposes according to the structure that the control film has completed before the yellow light process, and the process that has been performed. Of course, after the hard-bake process is completed, Before the completion of the yellow light process, it can also include several robotic arm conveying actions. When the wafer and the semiconductor wafer are transferred to the spin coating platform, the positioning is very accurate. After the wafer edge cleaning process, the remaining circular photoresist on the wafer The center of the layer will be concentric with the center of the wafer and the semiconductor wafer, so there will be no deviation. When the wafer or semiconductor wafer is transferred to the spin coating,

Page 12 540126 V. Description of the invention (8) When the positioning of the platform is wrong, the crystal edge, 杳, and taste make the μ μ ^ ^ m ^ ^ μ ^ u Day after day, after Xiao Cheng's process, the offset The phenomenon will occur. The eye is marked with a clear check mark on the control film, so when the inspection is performed after the development, you can use the spear 丨 2 ^ lower limit straight green 忑 1 4 to check the remaining photoresist layer and the upper The relative position of the lower limit line mark is used to monitor the transmission accuracy of the robot + π state robot arm. As shown in Figure 4A ^ t, when the manipulator splits; ^ a when the dentition is operating normally, the remaining photoresist layer 2 The edge of 0 2 will match your grasp. ^ ^ Will be located at the distance of the edge of the control piece 2 0 5fflm, which is exactly at the upper and lower limit of 硷 70, which accounts for 0 / ^, t. The center of No. 2 0 4. When there is a problem with the positioning of the robot arm, the position of the circular photoresist layer 202 on the control sheet 200 will shift, resulting in the result shown in Figure 4B. The above phenomenon is During the crystal edge cleaning process (step 106), the action of the cleaning mechanism itself is correct. However, the present invention can also be used to monitor the crystal edge cleaning machine. As shown in Figure 4C, 'When the positioning of the robot arm is normal, and the crystal edge is too wide (beyond the set value)', the edge of the circular photoresist layer 2 0 2 on the control plate 2 0 will be It is closer to the center of the control piece 2000 than normal. As shown in Figure 4D, when the positioning of the robot arm is normal and the crystal edge is too narrow (less than the set value), the rest of the control ^ 2 0 0 The edge of the circular photoresist layer 202 is closer to the edge of the control piece 200 than normal. As shown in the figure, when the transmission positioning of the robot arm is problematic and the crystal edge is too wide, the control piece The circular photoresist layer 202 remaining on 2000 not only shifts, but also the radius becomes smaller. As shown in Figure 4ρ, when the transmission positioning of the robot arm is problematic and the crystal edges are too narrow, the control piece The circular photoresist layer 2 on 2 0 2 not only shifts, but also has a larger radius.

Page 13 540126 V. Description of the invention (9) Due to the resistance of the coating to the remaining photoresist error, the correction of the operation (double line error caused a major monitoring of the crystal edge to see whether a slice occurred) for the positioning of light energy by Liang Jihe Whether or not ^ save unnecessary ADI steps to carry out the manufacturing process, and the method can also be used to know when the crystal edge is cleaned. The present invention uses ~ bubble and crystal edge cleaning to make the crystal, symmetrical crystal layer Judging by the relative position = this way, not only the time it takes. J to send the accuracy to the method of saving coffee, two: to provide a quick while LM to prevent post-development inspection, did not check immediately, recruiting Method f * Therefore, the Daxia product is lost. And the correctness of the mechanism of the present invention is correct: in the case of too wide or too small. Phase method, and phase manipulator of the crystal layer. You can stop the development and continue to make the crystals. You can use the marked wafers frequently. This 'not only can be set in the equipment.' It is not necessary to check for cancer (doub 1 e. If there is an error, there is no large loss. Wash the mechanism itself.) Moving machinery The resist coating process of the arm and the remaining photoresistance, and confirm the action. The same method, in order to prevent 'a large number of products, the method of the present invention, in order to know that compared to the conventional edge cleaning system of the present invention, the position of the arm can be provided The post-checking process is used to monitor whether the washing process is used in a process, because the recrystallized edges are widened or too small because of the accuracy of the discernment of the crystals, and the recrystallized edges are too wide or too small. The correct check is checked immediately. And what is done correctly is only the preferred embodiment of the present invention. Any application according to the present invention on page 14 540126

Page 15 540126 Brief description of the drawing 112 Development process 114 Inspection after development 130 Flow chart 200 Control sheet 202 Circular photoresist layer 204 Upper and lower limit line marks

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Claims (1)

540126 6. Scope of patent application 1. A method for monitoring the transmission accuracy of a main arm, the method includes the following steps: Provide a wafer with a plurality of marks on the surface, and the number of 4 indicates 0. A first distance from the center of the wafer, and the marks are symmetrical to each other; a spin-on device is used to coat the wafer surface with a photoresist layer; and a crystal edge is used to clean ( edge bevel rinse (EBR) device cleans the photoresist layer on the edge of the wafer to form a circular photoresist layer pattern and a ring region 'surrounding the circular photoresist layer pattern' on the wafer and Each outer edge of the circular photoresist layer pattern is at least a second distance from the center of the wafer; a photobake device is used to bake the photoresist layer on the surface of the wafer; Mask and an exposure device to expose the wafer; develop the wafer using a develop device; and perform an after development inspection (ADI) step To measure the difference between the first distance and each of the second distances, and then measure the transmission accuracy of the main arm. 2. The method according to item 1 of the patent application, wherein the wafer is a film thickness control wafer. 540126 VI. Application for patent scope 3. The method of the first patent scope, wherein the method for cleaning the photoresist layer by the crystal edge cleaning device includes: moving a nozzle to a standby position; using The robotic arm places the wafer at a wafer rotation position below the nozzle; moves the nozzle to a first position, and the first position is located outside a projection position directly above the wafer; and the wafer is at a constant speed Rotate and move the nozzle back and forth between the first position and a second position to clean the photoresist layer on the edge and edge of the wafer. 4. The method of claim 3, wherein the projection position of the second position on the wafer is about the second distance from the center of the wafer. 5. The method according to item 1 of the scope of patent application, wherein each of the marks further includes at least one sub-symbol that is symmetrical to each other, and each of the sub-marks is at a third distance from the center of the wafer. 6. The method according to item 5 of the patent application range, wherein the difference between the first distance and each of the second distances is equal, and each of the second distances is greater than the third distance. 7. The method of claim 5 in which each of the second distances is less than the third distance. Page 540 126 8. The method of claim 1 in the scope of patent application, wherein the difference between the first distance and each of the second distances is not equal. 9. The method according to item 1 of the patent application range, wherein each of the second distances is greater than the first distance. 10. —A method for detecting edge bevel rinse (EBR) and wafer edge exposure (WEE) abnormalities, the method includes the following steps: providing a wafer with a surface including a plurality of marks , The plurality of 4 shows that δ has a first distance from the center of the wafer, and the marks are symmetrical to each other; 'forming a thin film layer on the surface of the wafer; using an edge bevel rinse (EBR) The device cleans the thin film layer near the edge of the wafer to form a circular thin film layer pattern and a ring region surrounding the circular thin film layer pattern on the wafer. Each outer edge is at least a second distance from the center of the wafer; and an inspection step is performed to measure the difference between the first distance and the second distance. 11. The method of claim 10, wherein the thin film layer is a photoresist layer. 540126 6. Application for patent scope 1 2. The method according to item 11 of the patent application scope, wherein the method for cleaning the photoresist layer by the crystal edge cleaning device includes: moving a nozzle to a standby position; Using the robotic arm to place the wafer at a wafer rotation position below the nozzle; moving the nozzle to a first position, and the first position is located in an area other than a projection position directly above the wafer; and Rotate at a high speed and move the nozzle back and forth between the first position and a second position to clean the photoresist layer on the edge of the wafer. 1 3. The method according to item 12 of the scope of patent application, wherein the projection position of the second position on the wafer is about the second distance from the center of the wafer. 14. The method according to item 10 of the scope of patent application, wherein the difference between the first distance and each of the second distances is equal. 15. The method according to item 14 of the scope of patent application, wherein a difference between the first distance and each of the second distances is greater than a specification value. 16. The method according to item 14 of the scope of patent application, wherein a difference between the first distance and each of the second distances is less than a specification value. Page 21 540126 VI. Scope of patent application 1 7 · The method of item 14 of the patent application scope, wherein the difference between the first distance and each of the second distances is equal to a specification value. 18. The method of claim 10 in the scope of patent application, wherein the difference between the first distance and each of the second distances is not equal. Page 22