TW202406674A - Single-sided polishing methof for wafer, method for manufacturing wafer, and single-sided polishing device for wafer - Google Patents

Abstract

Provide a single-sided polishing method for wafers that can obtain wafers of desired shapes. The single-sided polishing method for wafers is a single-sided polishing method for wafers that presses a wafer held by a polishing head against a suede type polishing pad that is larger than the wafer, and uses a single-sided polishing equipment that polishing the wafer by rotating the polishing head and the polishing pad. The method has: a compressibility distribution calculation step finding a compressibility distribution on the radial direction of the polishing pad according to a target shape of the wafer after polishing; a polishing pad adjustment step adjusting the polishing pad to have the compressibility distribution; and a polishing step polishing the wafer using the polishing pad having the compressibility distribution.

Description

Single-side polishing method of wafer, manufacturing method of wafer, and single-side polishing device of wafer

The present invention relates to a single-side polishing method of a wafer, a wafer manufacturing method, and a single-side polishing device of a wafer.

The physical properties of the polishing pad's surface are known to affect processing margins when using a polishing pad to polish a single side of a wafer. As a technique for coping with such an influence, a technique for improving polishing performance by using a polishing pad with a ratio between surface roughness and compressibility within a specific range is known (for example, see Patent Document 1). As another technique, it is known to control the number of rotations of the table on which the polishing pad is arranged and the moving speed of the conditioning head in the radial direction of the table in accordance with the distance between the conditioning head and the center of the table. , a technique whereby the polishing pad surface is uniformly trimmed (for example, refer to Patent Document 2). As yet another technique, the correction amount of the surface shape is changed according to the position of the surface of the polishing cloth, thereby correcting the surface shape of the polishing cloth to correct the deviation of the pressure acting on the wafer (for example, see Patent Document 3). [Prior technical literature] [Patent Document]

[Patent Document 1] Japanese Patent Application Laid-Open No. 2003-142437 [Patent Document 2] Japanese Patent Application Publication No. 2017-064874 [Patent Document 3] Japanese Patent Application Laid-Open No. 2002-187059

[Problem to be solved by the invention]

However, as the requirements for the precision of the wafer shape, especially the ESFQR (Edge Site Flatness Front reference sQuare Deviation) of the wafer periphery, increase, as in the technologies described in Patent Documents 1 to 3, the polishing pad is The overall compressibility, or surface shape uniformity to obtain the desired shape of the wafer can become difficult.

An object of the present invention is to provide a single-side polishing method of a wafer capable of obtaining a wafer of a desired shape, a wafer manufacturing method, and a single-side polishing device of a wafer. [Means used to solve problems]

The single-side polishing method of a wafer according to the present invention presses the wafer held by the polishing head onto a suede-type polishing pad that is larger than the wafer, and rotates the polishing head and the polishing pad. The single-side polishing method of the wafer in the single-side polishing device for polishing the wafer includes: a compressibility distribution calculation step to obtain the radial compressibility distribution of the polishing pad based on the target shape of the polished wafer. ; a polishing pad adjustment step, adjusting the aforementioned polishing pad to have the aforementioned compression ratio distribution; and a polishing step, using the aforementioned polishing pad having the aforementioned compression ratio distribution to polish the aforementioned wafer.

In the single-side polishing method of the wafer of the present invention, it is preferable that the polishing pad adjustment step presses the brush against the polishing pad while rotating the polishing pad, thereby having a different compression ratio from other areas. The annular area is formed on the aforementioned polishing pad.

In the single-side polishing method of the wafer of the present invention, it is preferable that the polishing pad adjustment step forms the annular region so that the thickness of the region having the compressibility distribution is substantially equal.

In the single-side polishing method of the wafer of the present invention, it is preferable that the polishing step is to polish the wafer in a state where the wafer is located further outside the rotation center of the polishing pad, and the polishing pad adjustment step uses The brush forms an annular area, and the annular area is at a position where the rotation center of the polishing pad is set to 0% and a position on the outer edge of the wafer that is farthest from the rotation center. When the position is 100%, the position outside the 99% position and inside the 100% position is set as the inner edge area, and the compression rate is greater than the area inside.

In the single-side polishing method of a wafer of the present invention, it is preferable that the index of the target shape of the wafer is ESFQR.

In the single-side polishing method of the wafer of the present invention, it is preferable that the polishing step is to polish the wafer in a state where the wafer is located further outside the rotation center of the polishing pad, and the polishing pad adjustment step uses The brush forms an annular region such that three or more regions with different compression rates are arranged side by side in the radial direction, and the third region from the inside of the three or more regions with different compression rates is located on the polishing pad. When the rotation center is set to the 0% position and the position on the outer edge of the wafer farthest from the rotation center is set to the 100% position, the position further inside than the 100% position is set to the inner position. The circular area of the edge.

In the single-side polishing method of a wafer of the present invention, it is preferable that the index of the target shape of the wafer is GBIR.

In the single-side polishing method of a wafer of the present invention, it is preferable to include: a step of preparing a polishing device, performing the step of calculating the compressibility distribution and the polishing based on the target shapes that are different from each other on the plurality of single-side polishing devices. a pad adjustment step in which the compressibility distributions of the polishing pads respectively provided by the plurality of single-sided polishing devices are made different from each other; and a polishing device selection step in which the polishing target is selected from among the plurality of single-sided polishing devices. The wafer becomes the aforementioned single-sided polishing device with a set target shape, wherein the aforementioned polishing step uses the aforementioned single-sided polishing device selected in the aforementioned polishing device selecting step to polish the aforementioned wafer.

The wafer manufacturing method of the present invention includes a finishing step of finishing the wafer. In the finishing step, the wafer is polished by the above-mentioned single-side polishing method of the wafer.

The single-side polishing device for wafers of the present invention presses the wafer held by the polishing head against a suede-type polishing pad that is larger than the wafer, and rotates the polishing head and the polishing pad. A single-side polishing device for polishing the aforementioned wafer, including: a polishing pad adjustment portion to adjust the aforementioned polishing pad; a rotational drive portion to rotate the aforementioned polishing head and the aforementioned polishing pad; and a control device, wherein the aforementioned control device includes: compression rate distribution calculation a section that obtains the compressibility distribution in the radial direction of the polishing pad according to the target shape of the polished wafer; a polishing pad adjustment control section that controls the polishing pad adjustment section to adjust the polishing pad to have the compression rate distribution; and a polishing control unit that controls the rotation drive unit to polish the wafer using the polishing pad having the compression ratio distribution.

In the single-side polishing device for wafers of the present invention, it is preferable that the polishing pad adjustment unit includes a brush, and the polishing pad adjustment control unit controls the polishing pad adjustment unit to rotate the polishing pad while pressing the brush. to the aforementioned polishing pad, thereby forming an annular region having a different compressibility from other regions.

In the single-side polishing device for wafers of the present invention, it is preferable that the polishing pad adjustment unit includes a position adjustment unit for adjusting the position of the brush, and the polishing pad adjustment control unit controls the position adjustment unit so that the brush is positioned according to The height position of the aforementioned compression ratio.

[First Embodiment] Hereinafter, the first embodiment of the present invention will be described.

＜Configuration of single-sided polishing device＞ First, the single-side polishing device 1 according to the first embodiment of the present invention will be described with reference to the drawings. The single-side polishing device 1 shown in FIG. 1 polishes one side (the polished surface W1 ) of the wafer W (hereinafter, the polishing by the single-side polishing device 1 may be referred to as "single-side polishing"). The single-sided polishing device 1 includes a polishing section 2 , a polishing pad adjustment section 4 , and a control device 5 .

The polishing section 2 includes a polishing head 21, a head holding section 22, a head lifting section 23, a head driving section 24 as a rotational driving section, a fixed plate 25, a polishing pad 26, a fixed plate driving section 27 as a rotating driving section, and a wafer. The pressure adjusting part 28 and the polishing liquid supply part 29 are provided. In addition, although the polishing part 2 may be equipped with one polishing head 21, in this embodiment, the structure in which the polishing part 2 is equipped with a plurality of polishing heads 21 is illustrated.

Each polishing head 21 is formed in a disk shape. Each polishing head 21 holds the surface (back surface) of the wafer W opposite to the surface W1 (front surface) to be polished through the surface tension of water and the like.

A back pad 211 is provided on the lower surface of the polishing head 21 to cover the entire lower surface. The back pad 211 is made of, for example, a porous resin material, and can contain liquid such as water.

A ridge-shaped retainer ring 212 is arranged on the outer peripheral portion of the lower surface of the back pad 211 . The holding ring 212 contacts the outer peripheral end of the wafer W located inside the holding ring 212 and holds the wafer W so as not to fall out of the gap between the back pad 211 and the polishing pad 26 .

A cylindrical head rotation shaft member 213 is arranged at the center of the upper surface of each polishing head 21 .

The head holding part 22 holds the upper end side part of the head rotation shaft member 213 of each polishing head 21 so that the head rotation shaft member 213 can rotate around its axis. The head holding part 22 holds the head rotation shaft member 213 so that the plurality of polishing heads 21 are aligned at equal intervals on the circumference of a predetermined circle.

The head lifting part 23 raises and lowers the head holding part 22.

The head driving unit 24 is arranged inside the head holding unit 22 . The head drive unit 24 is composed of, for example, a motor, and rotates the head rotation shaft member 213 connected to the rotation shaft of the motor.

The fixed plate 25 is formed in a disk shape and is arranged below the plurality of polishing heads 21 . A cylindrical table rotation shaft member 251 is arranged at the center of the lower surface of the table 25 .

The polishing pad 26 is attached to the upper surface of the platen 25 . The polishing pad 26 is formed into a larger circular shape than the wafer W, and is configured to simultaneously polish the wafers W held by the plurality of polishing heads 21 . The polishing pad 26 is a suede-type soft polishing pad. The compression ratio of the polishing pad 26 is, for example, 23% or more and 36% or less. The polishing pad 26 has a Nap layer. The wafer W is polished by pressing the polished surface W1 of the wafer W against the Nap layer of the polishing pad 26 with a predetermined force. Here, the Nap layer refers to a layer formed by foaming and having a large number of pores.

The table driving part 27 is constituted by, for example, a motor, and rotates the table rotation shaft member 251 connected to the rotation shaft of the motor in the same direction or in the opposite direction to the rotation direction of the polishing head 21 .

The wafer pressing force adjusting unit 28 is a device that fixes the pressing method and adjusts the pressure pressing the wafer W against the polishing pad 26 . In the fixed pressure mode, the entire polishing head 21 is pushed downward through the pressure of a cylinder (cylinder), and the polishing head 21 is pressed to the upper surface of the wafer W through the back pad 211, thereby pressing the wafer W The surface to be polished W1 is pressed against the polishing pad 26 .

The polishing liquid supply part 29 supplies slurry-like polishing liquid to the polishing pad 26 through the nozzle 291 . This polishing liquid is used to polish the polished surface W1 of the wafer W.

In addition, the polishing part 3 may be provided with an oscillating drive unit for oscillating each polishing head 21 in a direction parallel to the polishing surface of the polishing pad 26 . For example, the swing drive holds the head lifting part 23 and causes the head lifting part 23 to reciprocate in one direction (for example, in the left-right direction in FIG. 1 ) during polishing of the wafer W, so that each polishing head 21 The polishing head 21 swings around the rotation axis D. Using such a swing drive unit, by swinging the polishing head 21 during polishing, the width of the outer peripheral portion of the wafer W to be polished can be adjusted through a predetermined adjustment area described later, and the wafer W of a desired shape can be obtained.

The polishing pad adjustment unit 4 adjusts the polishing pad 26 so that the polishing pad 26 has a radial compressibility distribution. The adjusted area of polishing pad 26 becomes more compressible and softer. The polishing pad adjustment part 4 includes a brush holding part 41, a brush 42, a position adjustment part 43, and the above-mentioned fixed plate and fixed plate driving part 27.

The brush holding part 41 includes a rod-shaped brush rotation shaft member 411 extending up and down. At the upper end of the brush rotation shaft member 411, a holding arm 412 extending in the horizontal direction is arranged.

The brush 42 is arranged at the front end side of the holding arm 412 . The brush 42 is composed of a plurality of nylon bristles bundled into a circular shape, and is formed into a shape smaller than the surface of the polishing pad 26 in plan view. Although the details will be described later, by rotating the polishing pad that presses the brush 42 , the compression ratio of the contact area between the polishing pad 26 and the brush 42 becomes high, and a compression ratio distribution is formed in the polishing pad 26 . As the brush 42 , the diameter of a cylindrical shape composed of bundled bristles is preferably 5 mm or less in order to improve the analysis ability of the compressibility distribution. In addition, the length of the bristles of the brush 42 is preferably 0.5 mm or more and 15 mm or less from the viewpoint of suppressing a change in the compression rate due to deformation of the bristles when the brush 42 is pressed against the polishing pad 26 .

The position adjustment part 43 adjusts the position of the brush 42. The position adjustment part 43 raises and lowers the brush rotation shaft member 411, thereby adjusting the height position of the brush 42. The position adjustment part 43 rotates the brush rotation shaft member 411 around its axis to thereby adjust the horizontal position of the brush 42 on the polishing pad 26 .

Here, a method of adjusting the polishing pad 26 to have a compressibility distribution using the polishing head adjustment unit 4 will be described. The position adjustment unit 43 presses the brush 42 against the polishing pad 26 in a state where the holding arm 412 is located at the position shown by the solid line as shown in FIG. 2 based on the control of the control device 5 . Next, the table driving unit 27 rotates the table 25 based on the control of the control device 5 . As the fixed plate 25 rotates, the annular first adjustment area 261 shown by the two-dot dotted line of the polishing pad 26 is adjusted. In addition, when the brush 42 is pressed against the polishing pad 26 with the holding arm 412 positioned at the position indicated by the two-dot dotted line, and the table plate 25 is rotated, the annular third portion of the polishing pad 26 shown by the two-dotted dotted line is rotated. 5 Adjustment area 265 is adjusted. Furthermore, by setting the position of the polishing pad 26 that presses the brush 42 to a predetermined position, the second adjustment area 262, the third adjustment area 263, and the fourth adjustment area 264 respectively indicated by two-dot dotted lines are adjusted.

The compression rate of the adjusted area (adjusted area) becomes greater than the compression rate of the area that has not been adjusted (unadjusted area), for example, the compression rate of the unadjusted area 260 located inside the first adjusted area 261 . In addition, the compression rate of the adjustment area increases as the amount of pressing of the brush 42 with respect to the polishing pad 26 becomes larger (the height position of the brush 42 becomes lower). In addition, when the amount of pressing of the brush 42 with respect to the polishing pad 26 is the same, the compression ratio of the adjustment area becomes larger as the adjustment time becomes longer. In addition, the thickness of the unadjusted area and each adjusted area is substantially equal regardless of the pressing amount of the brush 42 with respect to the polishing pad 26 . Therefore, the polishing pad adjustment part 4 can form an annular adjustment area on the polishing pad 26 so that areas with different compressibility are aligned in the radial direction of the polishing pad 26 and the thicknesses of areas with compressibility distribution are substantially equal. That is, the so-called compression ratio distribution refers to a distribution formed by annular adjustment areas with different compression ratios.

In addition, the higher the compression ratio of the polishing pad 26 is, the smaller the processing margin during polishing becomes. Therefore, for example, in order to make the compression rate of the outer region higher than that of the inner region, by forming a compression rate distribution on the polishing pad 26, it is possible to make the processing margin ratio of the outer region of the wafer W higher than that of the inner region. The inner areas have smaller machining margins.

In addition, in FIG. 2 , although the case where there are five annular adjustment areas with mutually different compression rates is illustrated, the number may be one or more and four or less, or six or more. In addition, the widths of the plurality of adjustment areas may be the same or different. Furthermore, the compression rate distribution may be formed so that the compression rate of the outer region is greater than the compression rate of the inner region, or it may be formed so that the compression rate of the outer region is smaller than the compression rate of the inner region. In addition, while moving the brush 42 in the horizontal direction, the entire polishing pad 26 can be adjusted. When adjusting the entire polishing pad 26, a brush that is the same size as the polishing pad 26 or larger than the polishing pad 26 in plan view may be used. Additionally, a plurality of brushes 42 of different sizes in plan view may be attached to the retaining arm 412 and the brushes 42 selected according to the size of the adjustment area of the polishing pad 26 .

The control device 5 controls the polishing section 2 and the polishing pad adjustment section 4 . As shown in FIG. 3 , the control device 5 includes an input unit 51 , a storage unit 52 , and a control unit 53 .

The input unit 51 is configured by, for example, a touch panel or physical buttons. The input unit 51 is used, for example, for input operations of various settings regarding polishing of the wafer W by an operator, and outputs signals corresponding to the input operations to the control unit 53 . As an input setting, the target shape of the polished surface W1 of the wafer W (hereinafter, sometimes referred to as the "target shape of the wafer W") can be exemplified. In addition, the input unit 51 may also obtain various setting information regarding polishing of the wafer W from an external network connected to the control device 5 .

Here, as indicators indicating the target shape of the wafer W, ESFQR, ZDD (Z-height Double Differentiation), and GBIR (Global flatness Back reference Ideal Range) can be exemplified.

ESFQR is an index indicating the site flatness at the outer peripheral portion (edge) of the wafer W. GBIR is an index indicating the global flatness of the wafer W. ESFQR and GBIR are measured using a flatness measuring device (for example, Wafer sight 2 manufactured by KLA-Tencor).

ESFQR divides the outer periphery of the wafer W into a large number (for example, 72) of sector-shaped areas (parts), and uses the inner plane of the part where the data in the part is calculated by the least squares method as the standard distance from the inner plane of the part. Displacement amount, each part has 1 data.

ZDD is an index indicating the change in slope (curvature) near the outer peripheral portion of the wafer W. ZDD is obtained by quadratic differentiation of the displacement profile of the wafer W from the center of the wafer W to the outermost periphery. A positive value of ZDD indicates that the surface is displaced in the rebound direction, whereas a negative value indicates that the surface is displaced in the sagging direction. The closer the value of ZDD is to 0, it means that the vicinity of the outer peripheral portion of the wafer W is not tilted (flat).

The memory unit 52 stores various information regarding polishing of the wafer W, for example, so that the control unit 53 can read the information. Examples of the information regarding polishing of the wafer W include first correlation information used for calculating the compressibility distribution of the polishing pad 26 and second correlation information used for calculating the adjustment conditions of the polishing pad 26 . In addition, the first related information and the second related information may be stored in, for example, a server device installed in a place far away from the single-sided polishing device 1 . In this case, the information stored in the server device can also be used by a plurality of single-side polishing devices 1 .

The first related information represents the radial compressibility distribution of the polishing pad 26 under preset polishing conditions (such as the pressure or polishing time to press the wafer W onto the polishing pad 26 ), and the shape of the wafer W after single-side polishing. correlation. Here, if the shape of the wafer W before single-side polishing is always the same, the first related information may have the above structure. However, when the shape of the wafer W before single-side polishing may be different, as the first relevant information, the compressibility distribution in the radial direction of the polishing pad 26 and the shape of the wafer W before and after single-side polishing may also be used. Information about shape correlations is applied. In addition, if the polishing conditions are always the same, the first related information may have the above configuration. However, when the polishing conditions may be different, the first relevant information may be the polishing conditions, the radial compressibility distribution of the polishing pad 26, and the wafer before and after single-side polishing (or after single-side polishing). The information related to the shape of W is applied.

The second related information represents the correlation between the radial compressibility distribution of the polishing pad 26 and the adjustment conditions of the polishing pad 26 . Examples of the adjustment conditions including the second related information include the pressing position, the pressing amount, and the adjustment time of the brush 42 with respect to the polishing pad 26 . In addition, the adjustment conditions may further include the size of the brush 42 or the hardness of the bristles.

In addition, the above-mentioned first related information and second related information may be information having a table structure, or may be information represented by a function.

The control unit 53 is provided with a CPU, and the CPU executes programs stored in the memory unit 52 to thereby realize various functions. The control unit 53 includes an information acquisition unit 531, a compression ratio distribution calculation unit 532, a polishing pad adjustment condition calculation unit 533, a polishing pad adjustment control unit 534, and a polishing control unit 535.

The information acquisition unit 531 acquires the first related information and the second related information from the memory unit 52 . The information acquisition unit 531 acquires, for example, the target shape information indicating the target shape of the wafer W set using the input unit 51 .

The compression ratio distribution calculation unit 532 obtains the compression ratio distribution in the radial direction of the polishing pad 26 based on the target shape of the wafer W after single-side polishing, based on the target shape information acquired by the information acquisition unit 531 and the first related information.

In addition, when the shape of the wafer W before single-side polishing may be different, the compressibility distribution calculation unit 532 may also calculate the polishing pad 26 based on the first relevant information including the shape of the wafer W before single-side polishing. radial compressibility distribution. In this case, the information acquisition unit 531 may acquire information indicating the shape before single-side polishing from the input unit 51, or may acquire information indicating the shape before single-side polishing from a shape measuring device. In addition, when the polishing conditions are sometimes different, the compression rate distribution calculation unit 532 may calculate the compressibility distribution in the radial direction of the polishing pad 26 based on the first relevant information including the polishing conditions. In this case, the information acquisition unit 531 may acquire information indicating the polishing conditions from the input unit 51 .

The polishing pad adjustment condition calculation unit 533 determines adjustment conditions for making the compression rate distribution of the polishing pad 26 become the compression rate distribution calculated by the compression rate distribution calculation unit 532 based on the second relevant information acquired by the information acquisition unit 531 .

The polishing pad adjustment control unit 534 controls the polishing pad adjustment unit 4 so as to adjust the polishing pad 26 based on the adjustment conditions obtained by the polishing pad adjustment condition calculation unit 533 .

The polishing control unit 535 controls the polishing unit 2 to rotate the polishing head 21 and the polishing pad 26 to polish the polished surface W1 of the wafer W.

＜Wafer manufacturing method＞ Next, a method of manufacturing the wafer W including a single-side polishing method of the wafer W using the single-side polishing apparatus 1 will be described. As shown in Figure 4, the manufacturing method of wafer W includes: a pulling step (step S1), a block processing step (step S2), a slicing step (step S3), a pre-processing step (step S4), and a simultaneous polishing step on both sides. (Step S5), a single-side finishing step (Step S6) as a finishing step, a cleaning step (Step S7), and a final wafer inspection step (Step S8).

In the pulling step of step S1, the Czochralski method is used to pull the cylindrical silicon single crystal from the silicon melt.

In the block processing step of step S2, the outer periphery of the single crystal ingot is ground and notch processing is performed according to the crystal orientation. Next, the single crystal ingot is cut into a plurality of blocks using, for example, a band saw.

In the slicing step of step S3, the block is sliced into a plurality of wafers W having a thickness of about 1 mm, for example, using an inner peripheral blade cutting machine, a wire saw, or the like.

In the pre-processing step of step S4, while chamfering is performed, rough polishing (lapping) is performed with, for example, an alumina polishing material, so that both surfaces of the wafer W become parallel. Next, after etching or the like is applied if necessary, a planarization process is performed to eliminate the unevenness on the surface of the wafer W.

In the double-side simultaneous polishing step of step S5, the pre-processed wafer W is subjected to mirror finishing to improve flatness. For example, colloidal silica (colloidal silica) liquid or the like is used to perform polishing on both sides to further improve the flatness to obtain a wafer W with a predetermined flatness.

The single-side finishing step of step S6 includes the single-side polishing method of the wafer W of the present invention. In the single-side finishing step, the single-side polishing device 1 is used to polish the polished surface W1 of the wafer W obtained by the two-side simultaneous polishing step. By applying the polishing process through the single-side finishing step, the surface roughness of the polished surface W1 can be adjusted while removing scratches and damage on the polished surface W1 of the wafer W. Details on the single-sided finishing steps are described later.

In the cleaning step of step S7, the wafer W obtained by the single-side finishing step is washed through, for example, an alkaline solution.

In the final wafer inspection step of step S8, surface particles, scratches, etc. existing on the wafer W are inspected using a wafer surface inspection device or the like. After conducting necessary quality inspections, qualified products are packaged and shipped.

Next, the details of the single-sided finishing step of step S6 will be described. As shown in Figure 5, the single-sided finishing step includes: a related information acquisition step (step S61), a target shape information acquisition step (step S62), a compression ratio distribution calculation step (step S63), and a polishing pad adjustment condition calculation step ( Step S64), polishing pad adjustment step (Step S65), wafer setting step (Step S66), polishing step (Step S67), and wafer removal step (Step S68).

In the related information acquisition step of step S61 , the information acquisition unit 531 of the control unit 53 acquires the first related information and the second related information from the storage unit 52 .

In the target shape information acquisition step of step S62, the information acquisition unit 531 acquires the target shape information based on the operator's input operation on the input unit 51. For example, the information acquisition unit 531 acquires information indicating ESFQR, ZDD or GBIR as the target shape information. In addition, the information acquisition unit 531 may acquire the target shape information from an external network via the input unit 51 .

In the compression rate distribution calculation step of step S63, the compression rate distribution calculation unit 532 calculates a calculation method for single-sided polishing based on the first correlation information acquired in the correlation information acquisition step and the target shape information acquired in the target shape acquisition step. The shape of the resulting wafer W becomes the compressibility distribution of the polishing pad 26 of the target shape.

Here, when the index representing the target shape information is ESFQR or ZDD, it is preferable to have a plurality of areas having mutually different compression rates formed by step S65: consisting of two areas, and as shown in the first As shown in FIG. 6 , it includes a circular unadjusted area 26A that has not been adjusted, and an adjusted area 26B that surrounds the unadjusted area 26A and is adjusted into an annular shape. On the other hand, when the index indicating the target shape information is ESFQR, the adjustment area 26B is at a position where the rotation center C of the polishing pad 26 is set to 0% and the wafer W is furthest from the rotation center C of the polishing pad 26 When the position on the outer edge is the 100% position, it is preferable to set the position outside the 99% position and inside the 100% position as an annular area on the inner edge and compress it. The ratio is larger than the inner unadjusted area 26A. In addition, when the index indicating the target shape information is ZDD, the adjustment area 26B may be formed at the same position as in the case of ESFQR, or may be formed further inside or outside than in the case of ESFQR. The compression rate and width of the adjustment area 26B differ according to the value of ESFQR or ZDD represented by the target shape information.

Here, if we want to specifically explain the above-mentioned 100% position in the case where the polishing part 2 is equipped with the swing driving part, in the case where the polishing part 2 is equipped with one polishing head 21, the polishing head 21 is arranged at the center of the swing width. The position on the farthest outer edge of the circle W from the rotation center C of the polishing pad 26 is the 100% position. In addition, when the polishing section 2 is provided with a plurality of polishing heads 21 and each polishing head 21 is arranged at the center of the swing range, the position on the outer edge of the wafer W that is farthest from the rotation center of the polishing pad 26 is 100 %s position. If expressed in another way, when the centers of the plurality of polishing heads 21 are equidistant from the center of the polishing pad 26, the position on the farthest outer edge of the wafer W from the rotation center C of the polishing pad 26 is 100%. .

By polishing using the polishing pad 26 with such a compressibility distribution, the processing margin of the area other than the outer peripheral portion of the wafer W polished with the unadjusted area 26A can be made almost the same. On the other hand, the process margin polished with the adjusted area 26B can be made almost the same. The processing margin of the outer peripheral portion of the wafer W is smaller than that of the inner region. In particular, the adjustment area 26B is set to be an annular area with the inner edge located outside the 99% position and inside the 100% position. By adjusting only the outer peripheral portion of the polishing pad 26 that contacts the wafer W, area, the outer peripheral shape of ESFQR, ZDD, etc. can be controlled without affecting the overall shape of the wafer W. In addition, the position of the outer edge of the adjustment area 26B is not particularly limited, but the position of 120% is shown in FIG. 6 .

In addition, when the index representing the target shape information is GBIR, the plurality of regions having mutually different compression rates formed through the step S65 includes three or more regions, and the third region from the inside is preferably : When the rotation center C of the polishing pad 26 is set to 0% and the position on the outer edge of the wafer W farthest from the rotation center of the polishing pad 26 is set to 100%, the ratio is 100%. The position further inside is the circular area on the inner edge. For example, a circular unadjusted area with the center at 0% and an outer edge at 25%, and a circular first adjustment area with an inner edge at 25% and an outer edge at 55%. , and the compression ratios of the annular second adjustment area where the inner edge is 55% and the outer edge is 120% are preferably different from each other. The compression rate and width of each adjustment area 26B differ according to the value of GBIR represented by the target shape information.

By polishing using the polishing pad 26 with such a compressibility distribution, the processing margin of the wafer W polished in each area in the radial direction can be gradually reduced toward the outer area, and the shape of the wafer W can be finely controlled. .

In addition, a circular area with the center at the 0% position and the outer edge at the 25% position may be set as the adjustment area. Alternatively, an annular area with the inner edge at the 25% position and the outer edge at the 55% position may be set as an unadjusted area. In this case, the processing margin of the center portion of the wafer W can be made small. By changing the compressibility distribution of the polishing pad 26 as described above, the distribution of the processing margin of the wafer W can be changed within the surface of the wafer W. In addition, by selecting the compressibility distribution according to the shape of the wafer W before polishing, a flatter wafer W can be manufactured.

In the polishing pad adjustment condition calculation step of step S64, the polishing pad adjustment condition calculation unit 533 calculates a calculation method for making the compression ratio distribution of the polishing pad 26 into a compression ratio distribution based on the second correlation information acquired in the correlation information acquisition step. The adjustment conditions for the compression ratio distribution determined by the calculation step.

In the polishing pad adjustment step of step S65, the polishing pad adjustment control unit 534 controls the position adjustment unit 43 and the platen driving unit 27 of the polishing pad adjustment unit 4 based on the adjustment conditions obtained in the polishing pad adjustment condition calculation step, and Adjust polishing pad 26. Through this polishing pad adjustment step, the polishing pad 26 capable of bringing the shape of the wafer W into the target shape can be obtained.

In the wafer setting step of step S66 , the wafer W obtained in the double-side simultaneous polishing step is set in the single-side polishing apparatus 1 .

In the polishing step of step S67, the polishing control unit 535 controls the head lifting unit 23, the head driving unit 24, the table driving unit 27, the wafer pressure adjusting unit 28, and the polishing unit 2 of the polishing unit 2 based on the preset polishing conditions. The liquid supply unit 29 polishes the wafer W using the polishing pad 26 adjusted by the polishing pad adjustment unit while swinging the polishing head 21 . Through this polishing step, a wafer W of the target shape can be obtained.

In the wafer removal step of step S68 , the wafer W is removed from the single-side polishing apparatus 1 . The taken-out wafer W is cleaned in the cleaning step of step S7.

<Effects of the first embodiment> According to the first embodiment, the single-sided polishing apparatus 1 includes the following steps: a compressibility distribution calculation step to obtain a radial compressibility distribution of the polishing pad 26 that can make the polished wafer W have a target shape; and a polishing pad adjustment step. , adjusting the polishing pad 26 to have the calculated compressibility distribution; and a polishing step of polishing the wafer W using the adjusted polishing pad 26 . In this way, by adjusting the radial compressibility distribution of the polishing pad 26 according to the target shape of the wafer W, the wafer W of the desired shape can be obtained by using the polishing pad 26 .

As the polishing pad 26, a suede type polishing pad is used. Therefore, the compressibility distribution can be easily formed in the polishing pad 26 .

As a method of forming a compressibility distribution in the polishing pad 26, a ring having a different compressibility from other areas is formed by pressing the brush 42 against the polishing pad 26 while rotating the suede-type polishing pad 26. area method. Therefore, a compressibility distribution can be formed in the polishing pad 26 by a simple method of using only the brush 42 and rotating the polishing pad 26 . In particular, by using the brush 42 with deformed bristles to adjust the suede-type polishing pad 26 instead of a cutting polishing pad 26 like a grindstone, the compression ratio can be finely adjusted efficiently without substantially increasing the thickness of the polishing pad 26. change. Furthermore, when the polishing pad 26 is adjusted using a grindstone, deterioration of the LPD (Light Point Defect) may occur due to adhesion of components of the grindstone to the polishing pad 26 . However, by using the brush 42 , the deterioration of the LPD can be suppressed.

When ESFQR is set as an index indicating the target shape of the wafer W, the polishing pad adjustment unit 4 preferably forms an annular region on the polishing pad 26 to include the compression ratio based on the control of the polishing pad adjustment control unit 534 The circular unadjusted area 26A and the annular adjusted area 26B are different from each other. In this case, the adjusted area 26B is formed in an annular shape with an inner edge located outside the 99% position and inside the 100% position, and has a greater compression ratio than the unadjusted area 26A. With this configuration, the shape of the outer peripheral portion of the wafer W can be controlled with high precision.

When setting the GBIR as an index indicating the target shape of the wafer W, the polishing pad adjustment unit 4 preferably forms an annular region on the polishing pad 26 to increase the compression rate based on the control of the polishing pad adjustment control unit 534 . Three or more regions that are different from each other are arranged side by side in the radial direction. With this configuration, the shape of the entire wafer W can be controlled with high precision.

The polishing pad adjustment unit 4 positions the brush 42 at a height position based on the compression ratio based on the control of the polishing pad adjustment control unit 534 . Therefore, by a simple method of merely adjusting the height position of the brush 42, the compression rate of the polishing pad 26 can be controlled with high precision. As a result, the shape of the wafer W can be controlled with higher precision.

[Second Embodiment] Next, a second embodiment of the present invention will be described. In the second embodiment, a structure in which a plurality of single-side polishing apparatuses 1 are used to polish the polished surfaces W1 of the wafer W into mutually different shapes will be described. In addition, since the structure of the single-side polishing apparatus 1 used in the second embodiment is the same as that of the single-side polishing apparatus 1 in the first embodiment, a method of manufacturing the wafer W including the single-side polishing method of the wafer W will be described. In addition, in the description of the manufacturing method of the wafer W, the same steps as those in the first embodiment are denoted by the same names and the same symbols and are briefly described.

As shown in FIG. 4 , the manufacturing method of the wafer W of the second embodiment differs from the manufacturing method of the first embodiment only in the single-side finishing step (step S9 ) as the finishing step.

As shown in FIG. 7 , the single-side finishing step of the second embodiment includes: a polishing device preparation step (step S91 ), a polishing device selection step (step S92 ), a wafer setting step (step S93 ), and a polishing step (step S93 ). S67), and the wafer removal step (step S68).

In the polishing device preparation step of step S91, the following steps are performed on the plurality of single-sided polishing devices 1: the related information acquisition step (step S61), based on mutually different target shapes, the polishing characteristics of the plurality of single-sided polishing devices 1 are obtained. The compression ratio distributions of the pads 26 are different from each other; the target shape information acquisition step (step S62); the compression ratio distribution calculation step (step S63); the polishing pad adjustment condition calculation step (step S64) and the polishing pad adjustment step (step S65). Through this polishing device preparation step, for example, when three single-sided polishing devices 1 are used, polishing pads 26 having different compressibility distributions can be prepared by performing steps based on three target shapes that are different from each other. 3 single-sided polishing devices 1.

In addition, the first related information and the second related information may not be stored in the memory unit 52 of each single-sided polishing device 1 but may be stored in the server device, and the information acquisition unit 531 of each single-sided polishing device 1 may obtain the information from the server device. Obtain the first relevant information and the second relevant information. In addition, the information acquisition unit 531 of each single-side polishing device 1 may acquire the target shape information from the input unit 51 of each single-side polishing device 1 . Alternatively, the operator may input target shape settings to a management device that collectively manages a plurality of single-side polishing devices 1, and the information acquisition unit 531 may acquire target shape information corresponding to the input settings.

In the polishing device selection step of step S92 , a single-side polishing device 1 for making the wafer W to be polished into a set target shape is selected from among the plurality of single-side polishing devices 1 . The selection of the single-side polishing device 1 may be performed by the operator inputting the target shape settings into the management device, and the management device may perform the selection based on the information corresponding to the inputted settings. In addition, the selection of the single-side polishing device 1 can also be based on the operator's judgment.

In the wafer setting step of step S93, the wafer W obtained by the two-side simultaneous polishing process is placed in the single-side polishing device 1 selected in the polishing device selection step.

The polishing step of step S67 and the wafer removal step of step S68 are performed in the single-side polishing device 1 selected in the polishing device selection step.

<Effects of the second embodiment> According to the second embodiment, the radial compressibility distributions of the polishing pads 26 of the plurality of single-sided polishing devices 1 are adjusted to be different from each other, and the wafer W is polished using the single-sided polishing device 1 selected according to the set target shape. . Therefore, wafers W of different desired shapes can be obtained simultaneously.

[Modification] Although the embodiments of the present invention have been described in detail with reference to the drawings, the specific configuration is not limited to the embodiments, and various improvements and design changes that do not deviate from the gist of the present invention are also included in the present invention.

For example, as a method of forming an annular region in the polishing pad 26 that has a compression rate different from other regions, a method of fixing the brush and rotating the polishing pad 26 is exemplified. However, the polishing pad may also be formed without rotating the polishing pad. 26 is rotated, or the brush 42 is moved while rotating the polishing pad 26 to draw a circle.

As a method of adjusting the amount of pressing of the brush 42 with respect to the polishing pad 26, a method of fixing the height position of the polishing pad 26 to adjust the height position of the brush 42 is exemplified. However, the height position of the brush 42 may be fixed or the height may be changed. At the same time, the height position of the polishing pad 26 is changed.

[Example] Next, examples of the present invention will be described. In addition, this invention is not limited to an Example.

[Example 1: Relationship between the adjustment time of the polishing pad and the properties of the adjusted polishing pad] First, the single-side polishing device 1 of the first embodiment is prepared. In addition, a plurality of suede-type polishing pads 26 having the following characteristics are prepared. Thickness of polishing pad 26: 0.94mm Compression ratio of polishing pad 26: 26.6%

The above-mentioned polishing pad 26 and the brush 42 made of nylon bristles with a length of 5 mm are installed in the single-sided polishing device 1 . The horizontal position of the brush 42 is adjusted to adjust the adjustment area 26B shown in FIG. 6 . At this time, the position of the inner edge of the adjustment area 26B is the 99.7% position, and the position of the outer edge is the 120% position. Furthermore, the height position of the brush 42 was adjusted so that the pressing amount of the brush 42 with respect to the polishing pad 26 becomes 0.5 mm. The pressing amount of the brush 42 is 0 mm when the bristles are not bent and the tips of the bristles are in contact with the polishing pad 26 .

Next, the fixed plate 25 was rotated for 30 seconds to adjust, and the polishing pad 26 of Example 1-1 was obtained. In addition, after the polishing pad 26 of the single-sided polishing device 1 was replaced with a polishing pad 26 that was not adjusted as a whole, polishing was performed under the same conditions as the polishing pad 26 of Example 1-1 except that the adjustment time was set to 60 seconds. The pad 26 was adjusted to obtain the polishing pad 26 of Example 1-2.

The thickness and compressibility of the outer peripheral portion (adjustment area) of the polishing pad 26 of Examples 1-1 and 1-2 were measured. The results are shown in Table 1. In addition, the polishing pad 26 of Comparative Example 1 is a polishing pad 26 that has not been adjusted as a whole.

[Table 1] polishing pad Comparative example 1 Example 1-1 Example 1-2 Adjust time without 30 seconds 60 seconds Polishing Pad Peripheral Thickness 0.94mm 0.94mm 0.94mm Compression ratio of polishing pad outer periphery 26.6% 27.3% 27.8%

As shown in Table 1, it can be confirmed that regardless of whether the outer peripheral portion of the polishing pad 26 is adjusted or the length of the adjustment time, while the thickness of the outer peripheral portion of the polishing pad 26 is almost the same, the adjustment time becomes longer. , the greater the compression ratio of the polishing pad 26 becomes. From this, it was confirmed that by adjusting the length of the adjustment time, the compression ratio can be adjusted without changing the entire thickness of the polishing pad 26 .

[Example 2: Relationship between the compressibility distribution of the polishing pad and the shape of the polished wafer] First, a plurality of wafers W having a diameter of 300 mm and the polished surface W1 having the same shape are prepared. Furthermore, the polishing pad 26 of Comparative Example 1 (a uniform polishing pad 26 with an overall compression rate of 26.6%) was attached to the single-sided polishing device 1 . Next, the wafer W was polished under preset polishing conditions to obtain the wafer W of Comparative Example 2. In addition, in addition to using the polishing pad 26 of Example 1-1 (the compression rate of the area from the center to the 99.7% position is 26.6%, and the compression rate of the area from the 99.7% position to the 120% position is 27.3% Another wafer W was polished under the same conditions as the wafer W of Comparative Example 2 except for the polishing pad 26) to obtain the wafer W of Example 2-1. Likewise, in the case where the polishing pad 26 of Example 1-2 was used (the compression rate of the area from the center to the 99.7% position was 26.6%, and the compression rate of the area from the 99.7% position to the 120% position was 27.8% Except for the polishing pad 26), another wafer W was polished under the same conditions as the wafer W of Comparative Example 2 to obtain the wafer W of Example 2-2.

Next, the polishing margin shape of the wafer W of Comparative Example 2 and Examples 2-1 and 2-2 was measured. The measurement results are shown in Figure 8. In addition, the horizontal axis of the graph shown in FIG. 8 represents the distance from the center of the wafer W, and the vertical axis represents: the differential profile of the thickness of the wafer W before and after polishing is calculated and the least squares method is used in the region to calculate the differential profile. The calculated displacement from the datum plane.

As shown in FIG. 8 , it can be confirmed that the outer peripheral portion of the wafer W of Example 2-2 has the smallest processing margin, and the outer peripheral portion of the wafer W of Comparative Example 2 has the largest processing margin. In other words, it can be confirmed that the flatness of the outer peripheral portion of the wafer W of Example 2-2 is the highest, and the flatness of the outer peripheral portion of the wafer W of Comparative Example 2 is the lowest.

In addition, measure the ZDD of ESFQR_max_1mm and the polished surface W1. The measurement results are shown in Table 2. In addition, ESFQR_max_1mm indicates the maximum displacement amount among the displacement amounts of each part when the area other than the range of 1 mm from the outer edge of each part is used as the measurement target.

[Table 2] wafer Comparative example 2 Example 2-1 Example 2-2 Compression ratio of polishing pad outer periphery 26.6% 27.3% 27.8% ESFQR_max_1mm 26.4nm 24.0nm 21.3nm Polished ZDD −7.2nm −5.9nm −3.9nm

As shown in Table 2, it can be confirmed that Example 2-2 has the smallest absolute values of ESFQR_max_1mm and ZDD, and Comparative Example 2 has the largest absolute values of ESFQR_max_1mm and ZDD.

From the results shown in Figure 8 and Table 2, it can be confirmed that if the compression ratio of the outer peripheral portion of the polishing pad 26 is larger than that of the inner region, the processing margin of the outer peripheral portion becomes smaller, and the polished surface becomes smaller. The flatness of W1 will become higher.

[Example 3: Relationship between the amount of pressing of the brush against the polishing pad and the properties of the polishing pad after adjustment] First, a plurality of suede-type polishing pads 26 having the following characteristics are prepared. Thickness of polishing pad 26: 0.93mm Compression ratio of polishing pad 26: 24.7%

The above-mentioned polishing pad 26 and the brush 42 made of nylon bristles with a length of 5 mm are installed in the single-sided polishing device 1 . The horizontal position of the brush 42 is adjusted to adjust the adjustment area 26B with the same position and shape as in the first embodiment. Furthermore, the height position of the brush 42 was adjusted so that the pressing amount of the brush 42 with respect to the polishing pad 26 becomes 0.5 mm.

Next, the fixed plate 25 was rotated for 30 seconds to adjust, and the polishing pad 26 of Example 3-1 was obtained. In addition, after the polishing pad 26 of the single-sided polishing device 1 was replaced with a polishing pad 26 that was not adjusted as a whole, the adjustment was performed under the same conditions as the polishing pad 26 of Example 3-1 except that the pressing amount was set to 0.8 mm. The polishing pad 26 of Example 3-2 was obtained. Furthermore, after the polishing pad 26 of the single-sided polishing device 1 was replaced with a polishing pad 26 that was not adjusted as a whole, the adjustment was performed under the same conditions as the polishing pad 26 of Example 3-1 except that the pressing amount was set to 1.1 mm. , the polishing pad 26 of Example 3-3 was obtained.

The thickness and compressibility of the outer peripheral portion (adjustment area) of the polishing pad 26 of Examples 3-1, 3-2, and 3-3 were measured. The results are shown in Table 3. In addition, the polishing pad 26 of Comparative Example 3 is a polishing pad 26 that has not been adjusted as a whole.

[table 3] polishing pad Comparative example 3 Example 3-1 Example 3-2 Example 3-3 Compression amount without 0.5mm 0.8mm 1.1mm Polishing Pad Peripheral Thickness 0.93mm 0.93mm 0.93mm 0.93mm Compression ratio of polishing pad outer periphery 24.7% 26.5% 26.8% 27.2%

As shown in Table 3, it can be confirmed that although the thickness of the outer peripheral portion of the polishing pad 26 is almost the same, regardless of whether the outer peripheral portion of the polishing pad 26 is adjusted or the magnitude of the pressing amount of the brush 42, the pressing amount becomes The larger, the greater the compressibility of the polishing pad 26 becomes. From this, it was confirmed that by adjusting the pressing amount of the brush 42 with respect to the polishing pad 26, the compression ratio can be adjusted without changing the thickness of the entire polishing pad 26. In addition, when the results of Example 1 are taken into consideration, it can be confirmed that by adjusting the length of the adjustment time in addition to the pressing amount of the brush 42 with respect to the polishing pad 26, the compression ratio can be more finely adjusted without changing the entire polishing pad 26. thickness.

[Example 4: Relationship between the pressing amount of the brush against the polishing pad and the shape of the polished wafer] First, a plurality of wafers W having a diameter of 300 mm and the polished surface W1 having the same shape are prepared. Furthermore, the polishing pad 26 of Comparative Example 3 (a uniform polishing pad 26 with an overall compression rate of 24.7%) was attached to the single-sided polishing device 1 . Next, the wafer W was polished under the same polishing conditions as in Example 2 to obtain the wafer W of Comparative Example 4. In addition, in addition to using the polishing pad 26 of Example 3-1 (the compression rate of the area from the center to the 99.7% position is 24.7%, and the compression rate of the area from the 99.7% position to the 120% position is 26.5% Another wafer W was polished under the same conditions as the wafer W of Comparative Example 4 except for the polishing pad 26) to obtain the wafer W of Example 4-1. Likewise, in the case where the polishing pad 26 of Example 3-2 was used (the compression rate of the area from the center to the 99.7% position was 24.7%, and the compression rate of the area from the 99.7% position to the 120% position was 26.8% Except for the polishing pad 26), another wafer W was polished under the same conditions as the wafer W of Comparative Example 4 to obtain the wafer W of Example 4-2. In addition, in addition to using the polishing pad 26 of Example 3-3 (the compression rate of the area from the center to the 99.7% position is 24.7%, and the compression rate of the area from the 99.7% position to the 120% position is 27.2% Another wafer W was polished under the same conditions as the wafer W of Comparative Example 4 except for the polishing pad 26), and the wafer W of Example 4-3 was obtained.

Next, the ESFQR_max_1mm and the ZDD of the polished surface W1 of the wafer W of Comparative Example 4 and Examples 3-1, 3-2, and 3-3 were measured. The measurement results are shown in Table 4.

[Table 4] wafer Comparative example 4 Example 4-1 Example 4-2 Example 4-3 Compression ratio of polishing pad outer periphery 24.7% 26.5% 26.8% 27.2% ESFQR_max_1mm 27.5nm 24.6nm 23.0nm 21.9nm Polished ZDD −9.8nm −7.2nm −5.6nm −3.7nm

As shown in Table 4, it can be confirmed that the absolute values of ESFQR_max_1mm and ZDD become smaller in the order of Comparative Example 4, Example 4-1, Example 4-2, and Example 4-3. From this, it was confirmed that, similarly to Example 2, if the compression ratio of the outer peripheral portion of the polishing pad 26 is greater than that of the inner region, the processing margin of the outer peripheral portion becomes smaller, and the flatness of the polished surface W1 decreases. will get higher.

1:Single side polishing device 2: Polishing Department 4: Polishing pad adjustment part 5:Control device 21: Polishing head 22:Head holding part 23: Head lifting part 24: Head drive part (rotary drive part) 25: Fixed price 26: Polishing pad 26A: Unadjusted area 26B:Adjustment area 27: Fixed plate drive unit (rotary drive unit) 28: Wafer pressure adjustment part 29: Polishing fluid supply department 41: Brush holding part 42:Brush 43: Position adjustment department 51:Input part 52:Memory Department 53:Control Department 211:Back pad 212:Retaining ring 213:Head rotating parts 251: Fixed plate rotating shaft parts 260: Unadjusted area 261: 1st adjustment area 262: The second adjustment area 263: The third adjustment area 264: The 4th adjustment area 265: The fifth adjustment area 291:Nozzle 411:Rotating shaft parts 412:Retaining arm 531:Information Acquisition Department 532: Compression ratio distribution calculation part 533: Polishing pad adjustment condition calculation unit 534: Polishing pad adjustment control section 535: Polishing control department C:Rotation center D:Rotation axis S1,S2,S3,S4,S5,S6,S7,S8,S9,S61,S62,S63,S64,S65,S66,S67,S68,S91,S92,S93: Steps W:wafer W1: Polished surface

FIG. 1 is a schematic diagram showing the schematic structure of the single-side polishing apparatus of the first embodiment and the second embodiment. Figure 2 is a plan view showing the adjustment method of the polishing pad according to the first and second embodiments. Fig. 3 is a block diagram showing the schematic structure of the control device of the first and second embodiments. FIG. 4 is a flowchart showing a wafer manufacturing method according to the first and second embodiments. Fig. 5 is a flowchart showing the steps of single-side finishing in the first embodiment. Fig. 6 is a schematic diagram showing an example of the compressibility distribution of the polishing pad according to the first and second embodiments. Fig. 7 is a flowchart showing the steps of single-side finishing in the second embodiment. Figure 8 is a graph showing the relationship between the compressibility distribution of the polishing pad of Example 2 and the shape of the polished wafer.

S6, S61, S62, S63, S64, S65, S66, S67, S68: Steps

Claims (12)

A single-side polishing method of a wafer, in which a wafer held by a polishing head is pressed onto a suede-type polishing pad larger than the wafer, and the polishing head and the polishing pad are rotated to thereby polish the wafer. The aforementioned single-side polishing device for wafers and the single-side polishing method for wafers have: a compressibility distribution calculation step to obtain the compressibility distribution in the radial direction of the polishing pad based on the target shape of the polished wafer; a polishing pad adjustment step, adjusting the aforementioned polishing pad to have the aforementioned compressibility distribution; and In the polishing step, the aforementioned polishing pad having the aforementioned compressibility distribution is used to polish the aforementioned wafer. The single-sided polishing method of the wafer as described in claim 1, wherein The polishing pad adjustment step presses the brush against the polishing pad while rotating the polishing pad, thereby forming an annular region having a different compression ratio from other regions on the polishing pad. The single-sided polishing method of the wafer as described in claim 2, wherein The aforementioned polishing pad adjustment step forms the aforementioned annular region so that the thickness of the regions having the aforementioned compressibility distribution is substantially equal. The single-sided polishing method of a wafer as described in claim 2 or claim 3, wherein The polishing step is polishing the wafer in a state where the wafer is located further outside the rotation center of the polishing pad, The aforementioned polishing pad adjustment step uses the aforementioned brush to form a circular area. When the rotation center of the polishing pad is set to 0% and the position on the outer edge of the wafer farthest from the rotation center is set to 100%, the annular region is The position outside of the 99% position and inside of the 100% position is an area of the inner edge, and is an area where the compression rate is greater than the area on the inside. The single-side polishing method of a wafer as described in claim 4, wherein the index of the target shape of the wafer is ESFQR. The single-sided polishing method of a wafer as described in claim 2 or claim 3, wherein The polishing step is polishing the wafer in a state where the wafer is located further outside the rotation center of the polishing pad, The aforementioned polishing pad adjustment step uses the aforementioned brush to form an annular area so that three or more areas with different compression rates are arranged side by side in the radial direction. Among the three or more regions with different compression ratios, the third region from the inside is at the position where the rotation center of the polishing pad is set to 0% and on the outer edge of the wafer farthest from the rotation center. When the position of is set to the 100% position, the position further inside than the 100% position is set to the annular area of the inner edge. The single-side polishing method of a wafer as described in claim 6, wherein the indicator of the target shape of the wafer is GBIR. The single-sided polishing method of the wafer as described in requirement 1 shall include: The polishing device preparation step includes performing the compression ratio distribution calculation step and the polishing pad adjustment step based on the target shapes that are different from each other on the plurality of single-side polishing devices, so that the polishing pads each of the plurality of single-side polishing devices are equipped with The compression ratio distributions become different from each other; and The polishing device selection step is to select the single-side polishing device that can make the wafer to be polished into a set target shape from the plurality of single-side polishing devices, The polishing step uses the single-sided polishing device selected in the polishing device selection step to polish the wafer. A wafer manufacturing method is a wafer manufacturing method and has: Finishing step, finishing the aforementioned wafer, In the aforementioned finishing step, the aforementioned wafer is polished through the single-side polishing method of the wafer described in claim 1. A single-side polishing device for wafers, which presses a wafer held by a polishing head onto a suede-type polishing pad larger than the wafer, and rotates the polishing head and the polishing pad to thereby polish the above-mentioned polishing pad. Single-side polishing device for wafers, equipped with: The polishing pad adjustment part adjusts the aforementioned polishing pad; a rotational driving part to rotate the aforementioned polishing head and the aforementioned polishing pad; and control device, The aforementioned control device includes: a compressibility distribution calculation unit that determines the compressibility distribution in the radial direction of the polishing pad based on the target shape of the polished wafer; a polishing pad adjustment control unit that controls the aforementioned polishing pad adjustment unit and adjusts the aforementioned polishing pad to have the aforementioned compression ratio distribution; and The polishing control unit controls the rotation drive unit to polish the wafer using the polishing pad having the compression ratio distribution. The single-side polishing device for wafers as described in claim 10, wherein The aforementioned polishing pad adjustment part is equipped with a brush, The polishing pad adjustment control unit controls the polishing pad adjustment unit to rotate the polishing pad and press the brush against the polishing pad, thereby forming an annular region having a different compression ratio from other regions. The single-side polishing device for wafers as described in claim 11, wherein The polishing pad adjustment part includes a position adjustment part for adjusting the position of the brush, The polishing pad adjustment control unit controls the position adjustment unit so that the brush is positioned at a height based on the compression ratio.