TWI739958B - Method for adjusting surface uniformity of wafer - Google Patents

Abstract

A method for adjusting surface uniformity of a wafer uses a boom-swing nozzle to spray reactive liquid on the wafer. In the method, first, a surface profile is measured, so as to obtain an initial uniformity. Next, the boom-swing nozzle performs a first boom-swing spray with a first boom-swing mode to change the surface profile of the wafer. The first boom-swing mode depends on the surface profile and the initial uniformity. After performing the first boom-swing spray, the boom-swing nozzle performs a second boom-swing spray with a second boom-swing mode to change the surface profile of the wafer. The second boom-swing mode is different from the first boom-swing mode.

Description

Method for adjusting wafer surface uniformity

The present invention relates to a semiconductor manufacturing process, and more particularly to a method for adjusting the uniformity of the wafer surface.

In the current manufacturing process of semiconductor components, wafers will inevitably be affected by semiconductor processes such as photolithography and etching, resulting in uneven surfaces with high surface uniformity (U%). , Where the higher the surface uniformity here, the rougher the wafer surface. Conversely, the lower the surface uniformity, the smoother the wafer surface. When the wafer has an uneven surface, the entire surface of the wafer may exhibit a convex profile or a concave profile, for example. However, whether it is a convex profile or a concave profile, this uneven surface is not conducive to subsequent manufacturing processes, and may result in a decrease in yield and even the risk of wafer scrap.

The present invention provides a method for adjusting the uniformity of the wafer surface, which uses a boom-swing nozzle to spray chemical liquid onto the wafer to help the wafer surface to become flat.

The method for adjusting the uniformity of the wafer surface provided by an embodiment of the present invention uses a swing-arm nozzle to spray chemical liquid on the wafer. In this method, first, the surface profile of the wafer is measured to obtain the initial uniformity. Then, the swing arm nozzle is used to perform the first swing-arm spraying process (boom-swing spray) according to the first swing arm mode to change the surface profile, wherein the first swing arm mode is determined according to the surface profile and the initial uniformity. After performing the first swing arm spraying process, the swing arm nozzle is made to perform a second swing arm spraying process according to a second swing arm mode to change the surface profile, wherein the second swing arm mode is different from the first swing arm mode.

In an embodiment of the present invention, during the first swing arm spraying process and the second swing arm spraying process, the wafer is rotated.

In an embodiment of the present invention, the amplitude of swing of the first swing arm mode is different from the amplitude of swing of the second swing arm mode.

In an embodiment of the present invention, a first swing arm speed change (variation of speed) of the first swing arm mode is different from a second swing arm speed change of the second swing arm mode.

In an embodiment of the present invention, when the measured surface profile of the wafer is a convex profile, the first swing arm spraying process and the second swing arm spraying process are performed. After performing the first swing arm spraying process and before performing the second swing arm spraying process, it also includes stopping the swinging of the swing arm nozzle to perform a static spraying process.

In an embodiment of the present invention, during the first swing arm spraying process, the swing arm nozzle swings at a constant rate.

In an embodiment of the present invention, during the second swing arm spraying process, the swing arm nozzle passes through the center of the wafer and swings between two opposite edges of the wafer, wherein the swing arm nozzle is in the center of the wafer It swings non-equally with one edge of the wafer.

In an embodiment of the present invention, the method for adjusting the uniformity of the wafer surface further includes after performing the second swing arm spraying process, making the swing arm nozzle perform the third swing arm spraying process according to the third swing arm mode to change Surface profile, where the third swing arm mode is different from the first swing arm mode and the second swing arm mode.

In an embodiment of the present invention, when the measured surface profile of the wafer is a concave profile, the first swing arm spraying process, the second swing arm spraying process, and the third swing arm spraying process are performed, and the second swing arm spraying process is performed. During the three-swing-arm spraying process, the velocity of the swing-arm nozzle in the center of the wafer is less than the velocity of the swing-arm nozzle on both sides adjacent to the center of the wafer.

The method for adjusting the uniformity of the wafer surface provided by another embodiment of the present invention uses a swing-arm nozzle to spray chemical liquid on the wafer. In this method, first, the surface profile of the wafer is measured to obtain the initial uniformity. Then, the swing arm nozzle is made to perform the swing arm spraying process according to the swing arm mode to change the surface profile. The swing arm mode in the swing arm spraying process is determined according to the surface profile and the initial uniformity. After the first swing arm spraying process, stop swinging of the swing arm nozzle to perform a static spraying process.

In the above embodiment of the present invention, the swing arm nozzle is used to perform at least one swing arm spraying process to change the distribution density of the chemical liquid in multiple areas on the wafer (such as the central area and the peripheral area), thereby changing the distribution density in these areas. Etching rate. In this way, the surface uniformity of the wafer can be reduced, and the surface of the wafer can be flattened.

In order to make the above-mentioned features and advantages more obvious and understandable, the following specific examples are given in conjunction with the accompanying drawings, and detailed descriptions are made as follows.

1A and 1B are schematic cross-sectional views of wafers that can be processed by the method for adjusting the uniformity of the wafer surface according to an embodiment of the present invention. Please refer to FIG. 1A and FIG. 1B. Both wafers 100a and 100b may be wafers that have undergone at least one semiconductor process. For example, the wafers 100a and 100b may both be wafers that have undergone at least one of deposition, lithography, and etching processes. Therefore, multiple semiconductor element prototypes can be formed on the surface of the wafers 100a and 100b, and the semiconductor element is, for example, a transistor. The wafers 100a and 100b have uneven surfaces. For example, the wafer 100a shown in FIG. 1A has a convex surface 101a, and the wafer 100b shown in FIG. 1B has a concave surface 101b.

Wafers 100a and 100b are semi-finished products that have not yet been completed. In other words, the wafers 100a and 100b must undergo subsequent processes such as baking, lithography, etching, and cleaning before being diced and packaged. However, since the wafers 100a and 100b have uneven surfaces (convex surface 101a and concave surface 101b), the uneven surface may cause a decrease in yield during subsequent semiconductor manufacturing processes. When the surface uniformity of both the convex surface 101a and the concave surface 101b is greater than 5%, the wafer 100a or 100b may need to be reworked. For example, in some semiconductor manufacturing processes today, when the surface uniformity of both the convex surface 101a and the concave surface 101b is greater than 5%, 10%, or 15%, the wafer 100a or 100b will need to be reworked. When the surface uniformity of both the convex surface 101a and the concave surface 101b is much greater than 15%, the wafer 100a or 100b may be forced to be scrapped. In this regard, the method for adjusting the uniformity of the wafer surface according to an embodiment of the present invention can change the surface contours of both the wafers 100a and 100b, and promote the flatness of the surfaces of the wafers 100a and 100b, thereby helping to improve the quality. Rate.

2A is a schematic top view of a swing arm spraying device used in a method for adjusting wafer surface uniformity according to an embodiment of the present invention, and FIG. 2B is a schematic side view of the swing arm spraying device in FIG. 2A. Please refer to FIG. 2A and FIG. 2B. The method of adjusting the uniformity of the wafer surface in this embodiment is performed by using a swing arm spraying device 200. In detail, the swing arm spraying device 200 includes a swing arm nozzle 210, and the method for adjusting the uniformity of the wafer surface in this embodiment is to use the swing arm nozzle 210 to spray the chemical liquid 21 on the wafer 201, wherein the chemical liquid 21 can be moved. In addition to the film and partical attached to the wafer 201 or removing part of the wafer 201 from the surface of the wafer 201, the chemical solution 21 can change the surface profile of the wafer 201.

The chemical solution 21 can be a cleaning solution, an etching solution, or a photoresist removal solution. Therefore, the method for adjusting the uniformity of the wafer surface in this embodiment can be performed in at least one of the three processes of cleaning, etching, and photoresist removal. The cleaning process It can be a cleaning process after etching or after removing the photoresist, wherein the aforementioned etching can be dry etching or wet etching. In addition, the wafer 201 shown in FIGS. 2A and 2B may be the wafer 100a shown in FIG. 1A or the wafer 100b shown in FIG. 1B, that is, the wafer 201 may have a convex surface 101a as shown in FIG. The concave surface 101b shown.

The swing arm spraying device 200 further includes a shaft 220, and the swing arm nozzle 210 includes a swing arm 211 and a nozzle head 212. The swing arm 211 is connected to the nozzle head 212, and the rotating shaft 220 is pivotally connected to the swing arm 211 so that the swing arm 211 can swing relative to the wafer 201 along the rotating shaft 220. Taking FIG. 2A as an example, the swing arm 211 can swing back and forth between two opposite edges E1 (right edge) and edge E2 (left edge) of the wafer 201, wherein the swing arm 211 can pass through the center C2 of the wafer 201. In this way, the swing arm nozzle 210 can spray the liquid medicine 21 onto the surface of the wafer 201 while swinging, so as to perform the swing arm spraying process. The swing arm spraying device 200 also includes a stage (not shown) that carries the wafer 201, which can spin to drive the wafer 201 to rotate, so that the liquid medicine 21 can be driven by centrifugal force to extend outward, and the crystal The rotation speed of the circle 201 may be about 1000 rpm.

3 is a schematic flowchart of a method for adjusting the uniformity of a wafer surface according to an embodiment of the present invention. 2A and 3, in the method for adjusting the uniformity of the wafer surface of this embodiment, first, step S301 is performed to measure the surface profile of the wafer 201 to obtain the initial uniformity, wherein the surface of the wafer 201 The contour and initial uniformity can be measured with an optical profilometer. After measuring the surface profile of the wafer 201, the entire surface of the wafer 201 can be known. For example, it is known that the entire surface of the wafer 201 exhibits a convex profile (as shown in FIG. 1A) or a concave profile (as shown in FIG. 1B). ).

When the measured initial uniformity is greater than 5%, for example, greater than 10% or 15%, step S302 is performed to perform the first swing arm spraying process, that is, the swing arm nozzle 210 performs the first swing arm in the first swing arm mode The spraying process is used to change the surface profile of the wafer 201, wherein the first swing arm mode is determined according to the surface profile measured in step S301 and the initial uniformity. When the measured initial uniformity is less than 5%, step S302 may not be performed, and a general regular process (regular process) may be performed instead, such as general cleaning, etching, and photoresist removal of wafers with normal uniformity. Waiting for the process.

Please refer to Figure 2A, Figure 3 and Figure 4A. 4A is a schematic diagram showing the relationship between the velocity of the swing arm nozzle 210 and the position of the wafer 201 in the first swing arm spraying process. That is to say, FIG. 4A also depicts the first swing arm mode of the first swing arm spraying process and its first swing arm rate change. In FIG. 4A, the horizontal axis represents the position of the wafer 201, and the vertical axis represents the velocity of the nozzle head 212 at different positions on the wafer 201. In detail, a value of zero on the horizontal axis of FIG. 4A indicates that the position is at the center C2 of the wafer 201, and the positive and negative values of the horizontal axis of FIG. 4A respectively represent the half of the center C2 of the wafer 201.

Take the wafer 201 shown in FIG. 2A as an example, the horizontal axis value 60 mm in FIG. 4A represents the position of the wafer 201 in the direction of 60 mm from the center C2 to the edge E1, and the horizontal axis value -20 mm in FIG. 4A It represents a position 20 mm from the center C2 to the edge E2 of the wafer 201. Therefore, the larger the absolute value of the horizontal axis value in FIG. 4A is, the closer the position is to the edge E1 or E2 of the wafer 201. Conversely, the smaller the absolute value of the horizontal axis value in FIG. 4A, the closer the representative position is to the center C2 of the wafer 201.

The velocity shown on the vertical axis of FIG. 4A is a relative velocity, which is a percentage of the maximum velocity of the nozzle head 212. In detail, when the swing arm spraying device 200 starts the swing arm nozzle 210 to swing, the nozzle head 212 has a maximum speed limit, and the relative speed shown on the vertical axis of FIG. 4A is a ratio of the maximum speed. Therefore, the maximum value of the vertical axis in Fig. 4A is 100%. In addition, in this embodiment, the maximum velocity of the nozzle head 212 may be 250 mm/sec.

In the first swing arm mode shown in FIG. 4A, the velocity of the nozzle head 212 in a position greater than 60 mm and less than -60 mm is zero. This means that the swing range of the swing arm nozzle 210 is approximately 60 mm to the left and right of the center C2 of the wafer 201. Therefore, the amplitude of swing of the swing arm nozzle 210 is 60 mm, that is, the nozzle head The displacement distance of 212 on wafer 201 is 120 mm. In addition, in this embodiment, the radius of the wafer 201 may be 150 mm. Therefore, when the nozzle head 212 is at a position greater than 60 mm or less than -60 mm, the nozzle head 212 is still about 90 mm away from the edge of the wafer 201 (for example, the edge E1 or E2).

It can be seen from FIG. 4A that in the process of performing step S302, when the nozzle head 212 is approximately between -60 mm and -20 mm and approximately between 60 mm and 20 mm, The velocity of the nozzle head 212 is basically a constant value and is 30% of the maximum velocity (for example, 250 mm/sec), which is, for example, 75 mm/sec. When the nozzle head 212 is approximately between -20 mm and 20 mm, the speed of the nozzle head 212 is basically a constant value, and is 50% of the maximum speed, which is, for example, 125 mm/sec. After step S302 is executed, then step S303 is executed to make the swing arm nozzle 210 perform the second swing arm spraying process according to the second swing arm mode to change the surface profile of the wafer 201, wherein the second swing arm mode is different from the first swing arm mode. One swing arm mode, and the second swing arm mode is shown in Figure 4B.

Please refer to Figure 2A, Figure 3 and Figure 4B. 4B is a diagram of the relationship between the swing arm nozzle velocity and the wafer position in the second swing arm spraying process in FIG. 3, wherein the horizontal axis of FIG. 4B is the same as the horizontal axis of FIG. 4A, and the vertical axis of FIG. 4B is also the same as that of FIG. The vertical axis of 4A, that is, the definitions of both the horizontal axis and the vertical axis of FIG. 4B are the same as the horizontal axis and the vertical axis of FIG. 4A, and the description will not be repeated here. In addition, in the second swing arm mode shown in FIG. 4B, the same as the first swing arm mode, the swing range of the swing arm nozzle 210 is also 60 mm to the left and right to the center C2 of the wafer 201. That is, the swing arm swing of the first swing arm mode is the same as the swing arm swing of the second swing arm mode. However, in the second swing arm mode of other embodiments, the swing arm swing of the second swing arm mode may also be different from the swing arm swing of the first swing arm mode shown in FIG. 4A.

Comparing FIGS. 4A and 4B, it can be seen that the first swing arm speed change of the first swing arm mode is different from the second swing arm speed change of the second swing arm mode. As shown in FIG. 4B, in the process of performing step S303, when the nozzle head 212 is approximately between -60 mm and -20 mm and approximately between 60 mm and 20 mm, the nozzle The speed of the head 212 is basically a constant value and is 20% of the maximum speed (for example, 250 mm/sec), which is, for example, 50 mm/sec. When the nozzle head 212 is approximately at a position between -20 mm and 20 mm, the speed of the nozzle head 212 is basically a constant value and is 60% of the maximum speed, which is, for example, 150 mm/sec. It can be seen that the speed change of the first swing arm in FIG. 4A is different from the speed change of the second swing arm in FIG. 4B.

When entering from the first swing arm spraying process (step S302) to the second swing arm spraying process (step S301), the nozzle head 212 is positioned at the center C2 of the wafer 201 and its vicinity (centered at the center C2, with a radius of 20 mm). The speed of the circular area inside) will increase from 50% of the maximum speed to 60% of the maximum speed, but in the peripheral area away from the center C2 (centered on the center C2, the radius is between 20 mm and 60 mm The annular area of the nozzle head 212 will decrease from 30% of the maximum velocity to 20% of the maximum velocity. It can be seen that the velocity of the nozzle head 212 in the central area of the wafer 201 increases, but the velocity of the peripheral area outside the central area decreases.

2A, 3, and 4C, after the second swing arm spraying process is performed, then step S304 is executed to make the swing arm nozzle 210 perform the third swing arm spraying process according to the third swing arm mode to change the crystal The surface profile of circle 201, in which the third swing arm mode is shown in Fig. 4C. The definitions of the horizontal axis and the vertical axis of FIG. 4C are the same as those of the horizontal axis and the vertical axis of FIG. 4A, so the description will not be repeated. Comparing FIGS. 4A to 4C, it can be seen that the third swing arm mode of FIG. 4C is different from the first swing arm mode of FIG. 4A and the second swing arm mode of FIG. 4B. In particular, the third swing arm rate change of the third swing arm mode is obviously different from the first swing arm rate change and the second swing arm rate change.

It can be seen from FIG. 4C that in the process of performing step S304, when the nozzle head 212 is approximately between -60 mm and -20 mm and approximately between 60 mm and 20 mm, The speed of the nozzle head 212 is not a fixed value, and is 20% to 25% of the maximum speed, for example, between 50 mm/sec and 62.5 mm/sec. The closer the nozzle head 212 is to the center C2 of the wafer 201, the nozzle The faster the speed of the head 212. When the nozzle head 212 is approximately between -20 mm and 20 mm, the speed of the nozzle head 212 is also indeterminate, and is 40% to 50% of the maximum speed, for example, between 100 mm/sec. Between 125 mm/sec, the closer the nozzle head 212 is to the center C2 of the wafer 201, the slower the speed of the nozzle head 212 is. In other words, the velocity of the swing-arm nozzle 210 at the center C2 of the wafer 201 is smaller than the velocity of the swing-arm nozzle 210 on both sides of the wafer 201 center C2. However, the velocity of the nozzle head 212 in the central area is still faster than the velocity in the peripheral area away from the center C2 (the annular area with the center C2 as the center and a radius between 20 mm and 60 mm).

In particular, during the first swing arm spraying process (step S302), the second swing arm spraying process (step S303), and the third swing arm spraying process (step S304), the swing arm spraying device 200 will rotate The wafer 201, so that the liquid medicine 21 (see FIG. 2B) on the wafer 201 can extend outward. In addition, in this embodiment, regardless of the first, second or third swing arm spraying process, the flow rate of the liquid medicine 21 output by the nozzle head 212 is constant regardless of the influence of the swing of the swing arm nozzle 210. However, in other embodiments, the nozzle head 212 can be set to output the liquid medicine 21 at different flow rates according to different swing arm spraying processes (for example, the first to third swing arm spraying processes). Therefore, the nozzle head 212 is not limited to outputting the liquid medicine 21 at a fixed flow rate.

Based on the above, the method for adjusting the uniformity of the wafer surface in this embodiment is to use the swing arm nozzle 210 to perform a multi-channel swing arm spraying process (for example, the first to third swing arm spraying processes) to spray the liquid chemical 21 on the wafer. 201 (see FIG. 2B), thereby changing the initial uniformity of the wafer 201, so that the surface uniformity of the wafer 201 is reduced, and the surface of the wafer 201 becomes flat. In this way, it is helpful to maintain or improve the yield rate and reduce the risk of wafer scrap.

In addition, in the first to third swing arm modes shown in FIGS. 4A to 4C, the nozzle head 212 is positioned at the center C2 of the wafer 201 and its vicinity (a circular area within a radius of 20 mm with the center C2 as the center). ) Is greater than the velocity in the peripheral area away from the center C2 (the ring area with the center C2 as the center and the radius between 20 mm and 60 mm). This can promote the distribution density of the chemical liquid 21 in the central area of the wafer 201 to be lower than the distribution density in the peripheral area of the wafer 201, so that the etching rate of the chemical liquid 21 on the peripheral area of the wafer 201 is greater than that of the central area of the wafer 201. In this way, the first to third swing arm spraying processes disclosed in FIGS. 4A to 4C are suitable for wafers with concave contours, such as the wafer 100b shown in FIG. 1B. In other words, when the measured surface profile of the wafer 201 is a concave profile (such as wafer 100b in FIG. 1B), the first swing arm spraying process (step S302) and the second swing arm spraying process (step S303) and the third swing arm spraying process (step S304) to help the surface of the wafer 201 with the concave contour to be flat.

It is worth mentioning that in the embodiment shown in FIG. 3, the method for adjusting the uniformity of the wafer surface may include performing a third swing arm spraying process, but in other embodiments, the method for adjusting the uniformity of the wafer surface is also It is not necessary to perform the third swing arm spraying process, such as the method disclosed in the following FIGS. 5 and 6A to 6C. Therefore, the method of adjusting the uniformity of the wafer surface is not limited to the third swing arm spraying process. In other words, step S304 shown in FIG. 3 can be omitted.

5 is a schematic flowchart of a method for adjusting the uniformity of a wafer surface according to another embodiment of the present invention, and FIGS. 6A to 6C sequentially disclose the first swing arm spraying process, the static spraying process, and the second swinging arm in FIG. 5 In the spraying process, the definitions of the horizontal axis and the vertical axis in FIGS. 6A to 6C are the same as the horizontal axis and the vertical axis in FIG. 4A, so the description will not be repeated. 2A and FIG. 5, the method of adjusting the uniformity of the wafer surface in this embodiment is similar to the foregoing embodiment. For example, this embodiment also uses the swing arm spraying device 200 shown in FIGS. 2A and 2B, and is also applicable to the wafer 201, where the radius of the wafer 201 can also be 150 mm. However, this embodiment is still different from the foregoing embodiments, and the following mainly introduces the differences between the two.

Specifically, in the method for adjusting the uniformity of the wafer surface in this embodiment, first, step S501 is performed to measure the surface profile of the wafer 201 to obtain the initial uniformity, wherein the measurement method can be the same as the previous embodiment. Step S301 in (see Figure 3). When the measured initial uniformity is greater than 5%, for example, greater than 10% or 15%, step S502 is executed to perform the first swing arm spraying process, that is, the swing arm nozzle 210 performs the first swing arm mode according to the first swing arm mode of FIG. 6A. A swing arm spraying process changes the surface profile of the wafer 201. The first swing arm mode in the first swing arm spraying process is determined according to the surface profile and initial uniformity. When the measured initial uniformity is less than 5%, step S502 may not be performed, or a general formal process may be performed instead, for example, the general cleaning, etching, and photoresist removal processes for wafers with normal uniformity .

Please refer to Figure 2A, Figure 5 and Figure 6A. FIG. 6A illustrates the first swing arm spraying process in step S502. Different from the first swing arm spraying process shown in FIG. 4A, during the first swing arm spraying process shown in FIG. 6A, the swing arm nozzle 210 will wait at a position between -60 mm and 60 mm. The velocity swing, where the velocity of the swing arm nozzle 210 is 40% of the maximum velocity. After the first swing arm spraying process is performed, then step S503 is executed to stop the swinging arm nozzle 210 to perform the static spraying process.

Please refer to FIG. 2A, FIG. 5 and FIG. 6B, where FIG. 6B illustrates the static spraying process of step S503. It can be seen from FIG. 6B that during the static spraying process shown in FIG. 6B, the swing arm nozzle 210 does not swing, and the nozzle head 212 is located at the center C2 of the wafer 201. In this way, the non-swing nozzle head 212 can increase the distribution density of the chemical liquid 21 (see FIG. 2B) in the central area of the wafer 201, so that the etching rate of the chemical liquid 21 on the central area of the wafer 201 can be greater than that of the periphery of the wafer 201 The etching rate of the area. After the static spraying process is performed, step S504 is executed to perform the second swing arm spraying process.

Please refer to FIG. 2A, FIG. 5 and FIG. 6C. FIG. 6C illustrates the second swing arm spraying process in step S504. It can be seen from FIG. 6C that during the second swing arm spraying process shown in FIG. 6C, the swing arm nozzle 210 swings between the two opposite edges E1 and E2 of the wafer 201, and is between -60 mm and -60 mm. The position between 60 mm swings at non-equal speed. At this time, the swing arm nozzle 210 passes through the center C2 of the wafer 201, and swings at a non-equal rate between the center C2 of the wafer 201 and one of the edges (for example, the edge E1 or E2) of the wafer 201. In addition, the closer the nozzle head 212 is to the center C2, the faster the velocity of the nozzle head 212 is. Conversely, the farther away the nozzle head 212 is from the center C2, the slower the velocity of the nozzle head 212 is. When the nozzle head 212 moves to the center C2, the speed of the nozzle head 212 can reach the maximum speed in the second swing arm mode, which can be 40% of the maximum speed (for example, 250 mm/sec), such as 100 mm/sec. Second.

It must be noted that during the first swing arm spraying process (step S502), the static spraying process (step S503), and the second swing arm spraying process (step S504), the swing arm spraying device 200 will rotate the wafer 201 to The liquid medicine 21 (see FIG. 2B) on the wafer 201 can extend outward. In addition, regardless of the impact of the swing of the swing arm nozzle 210, the flow rate of the liquid medicine 21 output by the nozzle head 212 is constant regardless of whether the first, second, or static spraying process is performed. However, in other embodiments, the nozzle head 212 can be set to output the liquid medicine 21 at different flow rates according to different swing arm spraying processes. Therefore, the nozzle head 212 is not limited to outputting the liquid medicine 21 at a fixed flow rate.

Based on the above, the static spraying process performed in this embodiment (as shown in FIG. 6B) can increase the distribution density of the chemical solution 21 in the central area of the wafer 201, and promote the etching rate of the chemical solution 21 to the central area of the wafer 201 to be greater than that of the opposite The etching rate of the peripheral area of the wafer 201. Therefore, the first swing arm spraying process, the static spraying process, and the second swing arm spraying process disclosed in FIGS. 6A to 6C are suitable for wafers with convex contours, such as the wafer 100a shown in FIG. 1A. In other words, when the measured surface profile of the wafer 201 is a convex profile (such as wafer 100a in FIG. 1A), the first swing arm spraying process (step S502) and the static spraying process (step S503) can be performed in sequence. ) And the second swing arm spraying process (step S504) to help the convex contour of the wafer 201 surface to be flat.

It is worth mentioning that, in the embodiment shown in FIG. 5, the method of adjusting the uniformity of the wafer surface can also increase the third swing arm spraying process. Therefore, the method for adjusting the uniformity of the wafer surface can also include three swing arm spraying processes, and it is not limited to only two swing arm spraying processes: the first and second swing arm spraying processes. In addition, in other embodiments, the method for adjusting the uniformity of the wafer surface in FIG. 5 may also omit step S504, that is, omit the second swing arm spraying process. Therefore, after performing step S501, the swing arm nozzle 210 can be made to perform the only swing arm spraying process in the swing arm mode (for example, step S502) to change the surface profile of the wafer 201, wherein the swing arm mode is based on this The surface profile and initial uniformity are determined. After the swing arm spraying process is performed, the swinging of the swing arm nozzle 210 is stopped, and the static spraying process is performed (for example, step S503). After that, no other swing arm spraying process is performed (for example, step S504).

In summary, the method for adjusting the uniformity of the wafer surface in the above embodiments of the present invention is to use the swing arm nozzle to perform at least one swing arm spraying process to change the chemical liquid on the wafer in multiple areas (such as the central area and the peripheral area). The distribution density within the region), thereby changing the etching rate in these regions. In this way, the surface uniformity of the wafer can be reduced, and the surface of the wafer can be promoted to be flat, thereby helping to maintain or improve the yield rate and reduce the risk of wafer scrap.

Although the present invention has been disclosed in the above embodiments, it is not intended to limit the present invention. Those with ordinary knowledge in the technical field to which the present invention pertains can make some changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be subject to those defined by the attached patent application scope.

21. ‧Nozzle head 220‧‧‧Shaft C2‧‧‧Center E1, E2‧‧‧Edge S301~S304, S501~S504‧‧‧Step

1A and 1B are schematic cross-sectional views of wafers that can be processed by the method for adjusting the uniformity of the wafer surface according to an embodiment of the present invention. 2A is a schematic top view of a boom-swing spraying apparatus used in a method for adjusting the uniformity of a wafer surface according to an embodiment of the present invention. Fig. 2B is a schematic side view of the swing arm spraying device in Fig. 2A. 3 is a schematic flowchart of a method for adjusting the uniformity of a wafer surface according to an embodiment of the present invention. FIG. 4A is a diagram of the relationship between the swing arm nozzle velocity and the wafer position in the first swing arm spraying process in FIG. 3. FIG. 4B is a diagram of the relationship between the swing arm nozzle velocity and the wafer position in the second swing arm spraying process in FIG. 3. 4C is a diagram of the relationship between the swing arm nozzle velocity and the wafer position in the third swing arm spraying process in FIG. 3. FIG. 5 is a schematic flowchart of a method for adjusting the uniformity of a wafer surface according to another embodiment of the present invention. FIG. 6A is a diagram of the relationship between the swing arm nozzle velocity and the wafer position in the first swing arm spraying process in FIG. 5. FIG. 6B is a graph of the relationship between the swing arm nozzle velocity and the wafer position in the static spraying process in FIG. 5. FIG. 6C is a diagram of the relationship between the swing arm nozzle velocity and the wafer position in the second swing arm spraying process in FIG. 5.

Steps S301, S302, S303, S304‧‧‧

Claims (9)

A method for adjusting the uniformity of the wafer surface, which uses a swing arm nozzle to spray a chemical liquid on a wafer. The method for adjusting the uniformity of the wafer surface includes: measuring a surface profile of the wafer to obtain a Initial uniformity; make the swing arm nozzle perform a first swing arm spraying process according to a first swing arm mode to change the surface profile, wherein the first swing arm mode is based on the surface profile and the initial uniformity Determine; and after performing the first swing arm spraying process, make the swing arm nozzle perform a second swing arm spraying process according to a second swing arm pattern to change the surface profile, wherein the second swing arm pattern is different In the first swing arm mode, the swing arm swing of the first swing arm mode is different from the swing arm swing of the second swing arm mode. The method for adjusting the uniformity of the wafer surface according to claim 1, wherein the wafer is rotated during the first swing arm spraying process and the second swing arm spraying process. The method for adjusting the uniformity of the wafer surface according to claim 1, wherein a first swing arm rate change of the first swing arm mode is different from a second swing arm rate change of the second swing arm mode. The method for adjusting the uniformity of the wafer surface according to claim 1, wherein when the measured surface profile of the wafer is a convex profile, the first swing arm spraying process and the second swing arm spraying process are performed The process, after performing the first swing arm spraying process and before performing the second swing arm spraying process, further includes: stopping the swinging arm nozzle to perform a static spraying process. The method for adjusting the uniformity of the wafer surface as described in claim 1 or 4, which During the spraying process of the first swing arm, the swing arm nozzle swings at a constant rate. The method for adjusting the uniformity of the wafer surface according to claim 1 or 4, wherein during the second swing arm spraying process, the swing arm nozzle passes through the center of the wafer, and is positioned on opposite sides of the wafer. Swing between edges, wherein the swing arm nozzle swings non-equally between the center of the wafer and one of the edges of the wafer. The method for adjusting the uniformity of the wafer surface as described in claim 1, further comprising: after the second swing arm spraying process, the swing arm nozzle is used to perform a third swing arm spraying according to a third swing arm pattern Process to change the surface profile, wherein the third swing arm mode is different from the first swing arm mode and the second swing arm mode. The method for adjusting the uniformity of the wafer surface according to claim 7, wherein when the measured surface profile of the wafer is a concave profile, the first swing arm spraying process and the second swing arm spraying process are performed And the third swing arm spraying process, and during the third swing arm spraying process, the speed of the swing arm nozzle in the center of the wafer is less than that of the swing arm nozzle on both sides adjacent to the center of the wafer rate. A method for adjusting the uniformity of the wafer surface, which uses a swing arm nozzle to spray a chemical liquid on a wafer. The method for adjusting the uniformity of the wafer surface includes: measuring a surface profile of the wafer to obtain An initial uniformity; let the swing arm nozzle perform a swing arm spraying process according to a swing arm mode to change the surface profile, wherein the swing arm mode is determined according to the surface profile and the initial uniformity, where During the spraying process of the swing arm, the nozzle of the swing arm swings at a constant rate; and after the spraying process of the swing arm is performed, the swing of the swing arm nozzle is stopped to perform a static spraying process.

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