Abrasive pad dressing condition setting method, wafer single side polishing method, wafer manufacturing method, abrasive pad dressing condition setting device and wafer single side polishing device

Abstract

To provide an abrasive pad dressing condition setting method by which a wafer of a desired shape can be obtained.SOLUTION: An abrasive pad dressing condition setting method comprises: an opening diameter acquisition process in which an opening diameter of a hole in a surface of an abrasive pad is acquired; a target shape acquisition process in which a target shape of a wafer after polishing is acquired; and a dressing condition setting process in which dressing condition of the abrasive pad is set. Correlation information represents correlation between the opening diameter of the abrasive pad, the dressing condition, and an estimated shape of a wafer which has been polished by the abrasive pad dressed under the dressing condition. The dressing condition setting process sets the dressing condition for making the wafer shape after polishing into the target shape on the basis of the opening diameter acquired in the opening diameter acquisition process and the target shape acquired in the target shape acquisition process.SELECTED DRAWING: Figure 6

Description

[Technical field]

[0001] The present invention relates to a method for setting dressing conditions for a polishing pad, a method for polishing one side of a wafer, a method for manufacturing a wafer, an apparatus for setting dressing conditions for a polishing pad, and an apparatus for polishing one side of a wafer. [Background technology]

[0002] It is known that when one side of a wafer is polished using a polishing pad, the physical properties of the surface of the polishing pad affect the amount of removal. As a technique for dealing with such an effect, a technique is known in which a polishing pad having a ratio of surface roughness to compressibility within a specific range is used to stabilize the quality of the wafer after polishing (see, for example, Patent Document 1). As another technique, a technique is known in which the surface shape of the polishing cloth is modified so as to correct the bias of the pressure acting on the wafer by changing the amount of modification of the surface shape depending on the position on the surface of the polishing cloth (see, for example, Patent Document 2). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2003-142437 A [Patent Document 2] JP 2002-187059 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, as the demand for precision in wafer shape, particularly in terms of ESFQD (Edge Site Flatness Front Reference Least Square Deviation) at the wafer periphery, increases, it is becoming difficult to obtain wafers of the desired shape simply by using a polishing pad with a specific range of surface roughness-to-compressibility ratio or by making the surface shape of the entire polishing cloth uniform, as in the techniques described in Patent Documents 1 and 2.

[0005] An object of the present invention is to provide a method for setting dressing conditions for a polishing pad, a method for polishing a single side of a wafer, a method for manufacturing a wafer, an apparatus for setting dressing conditions for a polishing pad, and an apparatus for polishing a single side of a wafer, which can produce a wafer of a desired shape. [Means for solving the problem]

[0006] The dressing condition setting method for a polishing pad of the present invention is a dressing condition setting method for a suede-type polishing pad used for single-sided polishing of a wafer, and comprises an opening diameter acquisition process for acquiring the opening diameter of a hole on the surface of the polishing pad, a target shape acquisition process for acquiring the target shape of the wafer after polishing, and a dressing condition setting process for setting the dressing conditions of the polishing pad based on correlation information, wherein the correlation information represents a correlation between the opening diameter of the polishing pad, the dressing conditions, and an estimated shape of the wafer polished by the polishing pad dressed under the dressing conditions, and the dressing condition setting process sets the dressing conditions for making the shape of the wafer after polishing the target shape based on the correlation information, the opening diameter acquired in the opening diameter acquisition process, and the target shape acquired in the target shape acquisition process.

[0007] In the method for setting dressing conditions for a polishing pad of the present invention, it is preferable that the correlation information represents a correlation between the opening diameter of the polishing pad, a plurality of different dressing conditions, and an estimated shape of the wafer polished by the polishing pad dressed under each of the plurality of dressing conditions, and the dressing condition setting process determines, based on the correlation information, an estimated shape of the wafer when the polishing pad whose opening diameter was acquired in the opening diameter acquisition process is dressed under each of the plurality of dressing conditions, selects from the estimated shapes thus obtained the estimated shape that is closest to the target shape, and sets the dressing conditions corresponding to the selected estimated shape as the dressing conditions for making the shape of the wafer after polishing the target shape.

[0008] The method for single-sided polishing of wafers of the present invention is a method for polishing a wafer by pressing the wafer against a suede-type polishing pad larger than the wafer and rotating the wafer and the polishing pad, and comprises a step of setting dressing conditions for the polishing pad by the above-mentioned method for setting dressing conditions for a polishing pad, a dressing step of dressing the polishing pad under the dressing conditions, and a polishing step of polishing the wafer with the dressed polishing pad.

[0009] In the method for polishing one side of a wafer of the present invention, it is preferable that the dressing step dresses the polishing pad by pressing a brush against the polishing pad while moving at least one of the brush and the polishing pad.

[0010] In the single-sided polishing method of the present invention, it is preferable that the dressing step dresses the polishing pad by rotating the polishing pad and moving the brush from the center to the outer periphery of the polishing pad, or from the outer periphery to the center.

[0011] In the single-sided polishing method of the present invention, it is preferable that the dressing condition setting step sets the dressing conditions in which at least one of the amount of pressing of the brush against the polishing pad and the number of dressings differs depending on at least one of the opening diameter of the polishing pad acquired in the opening diameter acquisition step and the target shape of the wafer acquired in the target shape acquisition step.

[0012] The method for producing a wafer of the present invention includes a finishing step for finishing the wafer, in which the wafer is polished by the above-mentioned method for single-sided polishing of a wafer.

[0013] The polishing pad dressing condition setting device of the present invention is a dressing condition setting device for a suede-type polishing pad used for single-sided polishing of a wafer, and is equipped with an information acquisition unit that acquires the opening diameter of a hole on the surface of the polishing pad and the target shape of the wafer after polishing, and a dressing condition setting unit that sets the dressing conditions of the polishing pad based on correlation information, wherein the correlation information represents the correlation between the opening diameter of the polishing pad, the dressing conditions, and the estimated shape of the wafer polished by the polishing pad dressed under the dressing conditions, and the dressing condition setting unit sets the dressing conditions for making the shape of the wafer after polishing into the target shape based on the correlation information, the opening diameter, and the target shape acquired by the information acquisition unit.

[0014] In the polishing pad dressing condition setting device of the present invention, it is preferable that the correlation information represents a correlation between the opening diameter of the polishing pad, a plurality of different dressing conditions, and an estimated shape of a wafer polished by the polishing pad dressed under each of the plurality of dressing conditions, and the dressing condition setting unit calculates an estimated shape of the wafer when the polishing pad, whose opening diameter has been acquired by the information acquisition unit, is dressed under each of the plurality of dressing conditions based on the correlation information, selects the estimated shape that is closest to the target shape from the estimated shapes thus obtained, and sets the dressing condition corresponding to the selected estimated shape as the dressing condition for making the shape of the wafer after polishing the target shape.

[0015] The single-sided polishing apparatus for wafers of the present invention is an apparatus for polishing wafers that polishes a wafer by pressing a wafer held by a polishing head against a suede-type polishing pad that is larger than the wafer and rotating the polishing head and the polishing pad, and is equipped with a dressing unit that dresses the polishing pad, a rotary drive unit that rotates the polishing head and the polishing pad, the above-mentioned dressing condition setting device that sets dressing conditions for the polishing pad, a dressing control unit that controls the dressing unit to dress the polishing pad under the dressing conditions, and a polishing control unit that controls the rotary drive unit to polish the wafer with the dressed polishing pad.

[0016] In the single-sided polishing apparatus for wafers of the present invention, it is preferable that the dressing control unit controls the dressing unit to dress the polishing pad by pressing a brush against the polishing pad while moving at least one of the brush and the polishing pad.

[0017] In the single-sided polishing apparatus for wafers of the present invention, it is preferable that the dressing control unit controls the dressing unit to dress the polishing pad by rotating the polishing pad and moving the brush from the center to the outer periphery of the polishing pad, or from the outer periphery to the center.

[0018] In the single-sided polishing apparatus for wafers of the present invention, it is preferable that the dressing condition setting unit sets the dressing conditions in which at least one of the amount of pressing of the brush against the polishing pad and the number of dressings differs depending on at least one of the opening diameter of the polishing pad and the target shape of the wafer acquired by the information acquisition unit. [Brief description of the drawings]

[0019] [Figure 1] 1 is a schematic diagram showing a schematic configuration of a single-sided polishing apparatus for a wafer according to an embodiment; [Diagram 2] 1A to 1C are plan views showing a method for dressing a polishing pad according to an embodiment. [Diagram 3] 1 is a block diagram showing a schematic configuration of a control device according to an embodiment; [Figure 4] FIG. 13 is a schematic diagram illustrating correlation information in a graph format according to the embodiment. [Diagram 5] 3 is a flowchart showing a method for manufacturing a wafer according to an embodiment. [Figure 6] 10 is a flowchart showing a single-sided finishing process according to an embodiment. [Figure 7] 1 is a graph showing the correlation between the average aperture ratio and ZDD on the wafer surface when unused according to Example 1. [Figure 8] FIG. 13 is a diagram showing the correlation between the brush pressing amount during dressing and the ZDD of the wafer surface in Example 2. [Figure 9] FIG. 13 is a diagram showing the correlation between the brush pressing amount during dressing and ESFQD in Example 2. [Figure 10] FIG. 13 is a diagram showing the correlation between the average opening diameter when not in use, the brush pressing amount during dressing, and the ZDD of the wafer surface according to Example 3. [Figure 11] FIG. 13 is a diagram showing the correlation between the average opening diameter when unused, the brush pressing amount during dressing, and ESFQD according to Example 3. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] [Embodiment] <Configuration of single-sided wafer polishing equipment> First, the configuration of a single-side polishing apparatus for wafers according to an embodiment of the present invention will be described. 1 polishes one side (surface to be polished W1) of a wafer W (hereinafter, polishing in the single-sided polishing apparatus 1 may be referred to as “single-sided polishing”). The single-sided polishing apparatus 1 includes a polishing unit 2, a dressing unit 4, a code reading unit 5, and a control device 6.

[0021] 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 rotation driving section, a surface plate 25, a polishing pad 26, a surface plate driving section 27 as a rotation driving section, a wafer pressure adjustment section 28, and a polishing liquid supply section 29. Although the polishing unit 2 may include one polishing head 21, the present embodiment illustrates a configuration in which the polishing unit 2 includes a plurality of polishing heads 21.

[0022] 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 by using the surface tension of water or the like.

[0023] A back pad 211 is disposed on the lower surface of the polishing head 21 so as 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.

[0024] A ring-shaped retainer ring 212 is disposed on the outer periphery of the lower surface of the back pad 211. The retainer ring 212 comes into contact with the outer periphery of the wafer W located inside the retainer ring 212, and holds the wafer W so that it does not come out of the gap between the back pad 211 and the polishing pad 26.

[0025] A cylindrical head rotating shaft member 213 is disposed in the center of the upper surface of each polishing head 21.

[0026] The head holding unit 22 holds the upper end portion 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 unit 22 holds the head rotation shaft member 213 so that the multiple polishing heads 21 are arranged at equal intervals on the circumference of a predetermined circle.

[0027] The head lifting unit 23 lifts and lowers the head holding unit 22 .

[0028] The head driving unit 24 is disposed inside the head holding unit 22. The head driving unit 24 is configured by, for example, a motor, and rotates a head rotation shaft member 213 connected to the rotation shaft of the motor.

[0029] The surface plate 25 is formed in a disk shape, and is disposed below the plurality of polishing heads 21. A cylindrical surface plate rotating shaft member 251 is disposed in the center of the lower surface of the surface plate 25.

[0030] The polishing pad 26 is attached to the upper surface of the surface plate 25. The polishing pad 26 is formed in a circular shape larger than the wafer W, and is configured to be able to simultaneously polish the wafers W held by the multiple polishing heads 21. The polishing pad 26 is a suede-type soft polishing pad. The compressibility of the polishing pad 26 is, for example, 23% or more and 36% or less. The polishing pad 26 has a nap layer. The nap layer is a layer having a large number of holes formed by foaming. The pad surface 261 of the polishing pad 26 has openings of the many holes that the nap layer has. The polished surface W1 of the wafer W is pressed against the pad surface 261 with a predetermined force, whereby the wafer W is polished.

[0031] The platen driving unit 27 is constituted by, for example, a motor, and rotates a platen rotating shaft member 251 connected to the rotating shaft of the motor in the same direction as the rotating direction of the polishing head 21 or in the opposite direction.

[0032] The wafer pressure adjustment unit 28 is a fixed pressure type device that adjusts the pressure with which the wafer W is pressed against the polishing pad 26. In the fixed pressure type, the entire polishing head 21 is pressed down by cylinder pressure, and the polishing head 21 is pressed against the upper surface of the wafer W via the back pad 211, whereby the polished surface W1 of the wafer W is pressed against the polishing pad 26.

[0033] The polishing liquid supply unit 29 supplies a slurry-like polishing liquid to the polishing pad 26 through a nozzle 291. The surface W1 to be polished of the wafer W is polished using the polishing liquid.

[0034] The polishing unit 2 may be provided with a swing drive unit that swings each polishing head 21 in a direction parallel to the polishing surface of the polishing pad 26. For example, the swing drive unit holds the head lift unit 23 and moves the head lift unit 23 back and forth in one direction (for example, back and forth in the left and right direction in FIG. 1) during polishing of the wafer W, thereby swinging each polishing head 21 about the rotation axis D of the polishing head 21.

[0035] The dressing unit 4 dresses the polishing pad 26 so that the average value of the opening diameters of the multiple openings present in the pad surface 261 of the polishing pad 26, i.e., the average opening diameter, becomes a predetermined value. In the dressed region of the pad surface 261, the opening diameter of the pores becomes larger and the pad surface 261 becomes softer. The dressing unit 4 includes a brush holder 41, a brush 42, a position adjuster 43, and the above-mentioned surface plate 25 and surface plate driver 27.

[0036] The brush holder 41 includes a vertically extending rod-shaped brush rotating shaft member 411. A horizontally extending holding arm 412 is disposed on the upper end of the brush rotating shaft member 411.

[0037] The brush 42 is disposed at a portion on the tip side of the holding arm 412. The brush 42 is composed of a plurality of nylon bristles bound together in a circular shape, and is formed into a shape smaller than the pad surface 261 in a plan view. As described in more detail below, by rotating the polishing pad 26 against which the brush 42 is pressed, the opening diameter of the pores in the contact area between the pad surface 261 and the brush 42 increases, and the average opening diameter of the pad surface 261 increases.

[0038] The position adjustment unit 43 adjusts the position of the brush 42. The position adjustment unit 43 adjusts the height position of the brush 42 by raising and lowering the brush rotating shaft member 411. The position adjustment unit 43 adjusts the horizontal position of the brush 42 on the pad surface 261 by rotating the brush rotating shaft member 411 around its axis.

[0039] Here, a method of dressing the polishing pad 26 using the dressing unit 4 so as to increase the average opening diameter of the pad surface 261 will be described. The position adjustment unit 43, under the control of the control device 6, presses the brush 42 against the pad surface 261 with the holding arm 412 positioned at the center of the pad surface 261 indicated by the solid line, as shown in Fig. 2. Next, the surface plate driving unit 27, under the control of the control device 6, rotates the surface plate 25 multiple times at a uniform speed in the counterclockwise direction in Fig. 2. Also, while the surface plate 25 is rotating multiple times, the position adjustment unit 43, under the control of the control device 6, rotates the holding arm 412 at a uniform speed in the counterclockwise direction in Fig. 2, and moves it from the center of the pad surface 261 to the outer periphery indicated by the two-dot chain line. With such rotation of the polishing pad 26 and movement of the brush 42 from the center to the outer periphery of the pad surface 261, an annular dressing region 261A indicated by a two-dot chain line on the pad surface 261 is dressed. The rotation directions of the platen 25 and the holding arm 412 may be different. In order to dress the dressing area 261A, the brush 42 may be moved from the outer periphery of the pad surface 261 to the center.

[0040] The opening diameter of the hole in the dressing region 261A increases as the pressing amount of the brush 42 against the polishing pad 26 (hereinafter, may be referred to as "brush pressing amount") increases, that is, as the height position of the brush 42 decreases. Furthermore, when the brush pressing amount is the same, the opening diameter of the hole in the dressing region 261A becomes larger as the number of dressing operations increases. Additionally, the thickness of the dressed area 261A and the undressed area will be substantially equal regardless of the brush pressure or the number of dressings.

[0041] Moreover, the larger the average opening diameter of the pad surface 261, the smaller the removal allowance when polishing the outer periphery (edge) of the wafer W. Therefore, by adjusting the average opening diameter of the pad surface 261 according to the target shape of the polished surface W1 of the wafer W (hereinafter sometimes referred to as the "target shape of the wafer W"), a wafer W having the target shape can be manufactured.

[0042] The brush 42 may be moved linearly along the horizontal direction while rotating the polishing pad 26. The entire polishing pad 26 may be dressed using a brush that is the same size as the polishing pad 26 or larger than the polishing pad 26 in a plan view.

[0043] 1 is electrically connected to the control device 6. The code reading unit 5 reads a one-dimensional code or a two-dimensional code attached to the polishing pad 26 itself or to a box that contains at least one polishing pad 26, and outputs a signal corresponding to the read content to the control device 6. The one-dimensional code or the two-dimensional code has information that specifies the average opening diameter of the pad surface 261 of the polishing pad 26.

[0044] The control device 6 controls the polishing unit 2 and the dressing unit 4. As shown in FIG.

[0045] The input unit 61 is configured with, for example, a touch panel or physical buttons. The input unit 61 is used to input various information, and outputs a signal corresponding to the input to the control unit 64. The input settings may include a target shape of the wafer W, for example. The input unit 61 may acquire various setting information related to polishing of the wafer W from an external network connected to the control device 6.

[0046] Here, examples of indices that represent the target shape of the wafer W include ESFQD and ZDD (Z-height Double Differentiation).

[0047] The ESFQD is an index indicating the site flatness at the outer periphery of the wafer W. The ESFQD is measured by a flatness measuring device (for example, Wafer sight 2 manufactured by KLA-Tencor).

[0048] The outer periphery of the wafer W is divided into many (e.g., 72) sector-shaped regions (sites), and the ESFQD is calculated by fitting the data within the site to a plane within the site using the least squares method.The ESFQD is the maximum displacement, without sign, from this plane within the site, and each site has one piece of data.

[0049] The ZDD is an index that represents the change in inclination (curvature) near the outer periphery of the wafer W. The ZDD is obtained by second-order differentiation of the displacement profile of the surface of the wafer W (polished surface) from the center of the wafer W to the outermost periphery. On the front side of the wafer W, a positive ZDD value indicates that the surface is displaced in the direction of bouncing, and a negative ZDD value indicates that the surface is displaced in the direction of sagging. The closer the ZDD is to 0, the less inclination there is near the outer periphery of the wafer W (the flatter it is).

[0050] The display unit 62 displays various information based on the control of the control unit 64.

[0051] The storage unit 63 is configured with a well-known storage device such as a HDD (Hard Disk Drive). The storage unit 63 stores various information related to, for example, polishing of the wafer W in a manner readable by the control unit 64. As the information related to polishing of the wafer W, correlation information used for setting the dressing conditions of the polishing pad 26 can be exemplified. The correlation information may be stored in, for example, a server device installed at a location remote from the single-sided polishing apparatus 1. In this case, the information stored in the server device may be made available to a plurality of single-sided polishing apparatuses 1.

[0052] The correlation information shown in Figure 4 represents the correlation between the average opening diameter of the pad surface 261 of an unused polishing pad 26 (hereinafter sometimes referred to as the "average opening diameter when unused") under preset polishing conditions (e.g., the pressure for pressing the wafer W against the polishing pad 26 and the polishing time) and the estimated shape of the wafer W after single-sided polishing using the unused polishing pad 26 that has been dressed under multiple different dressing conditions. Fig. 4 shows correlation information when the index representing the estimated shape of the wafer W is the ZDD of the surface of the wafer W. The second dressing condition shown in Fig. 4 is stricter than the first dressing condition, and the third dressing condition is lenient than the first dressing condition. For example, when the number of dressings under the first to third dressing conditions is the same and the brush pressing amount under the first dressing condition is A mm, the brush pressing amount under the second dressing condition is C mm which is larger than A mm, and the brush pressing amount under the third dressing condition is D mm which is smaller than A mm.

[0053] If the dressing conditions and polishing conditions are the same, the larger the average opening diameter when unused, the larger the estimated ZDD value of the surface of the wafer W, and there is a linear proportional relationship between the average opening diameter when unused and the estimated ZDD value of the surface of the wafer W. The correlation between the average opening diameter when unused and the estimated ZDD value of the surface of the wafer W may be expressed by an approximation formula of multiple experimental data, or may be obtained by simulation. Furthermore, if the average opening diameter and polishing conditions when unused are the same, the stricter the dressing conditions, i.e., the greater the brush pressure, the larger the estimated ZDD of the wafer W surface will be, and the looser the dressing conditions, i.e., the smaller the brush pressure, the smaller the estimated ZDD of the wafer W surface will be.

[0054] The correlation information may represent correlations corresponding to two or four or more different dressing conditions. In addition, the multiple dressing conditions represented by the correlation information may differ in the brush pressure amount and the number of dressings, or may differ only in the number of dressings. When the number of dressings of the multiple dressing conditions represented by the correlation information is different, if the average opening diameter and polishing conditions when unused are the same, the more the number of dressings, the larger the estimated value of the ZDD of the wafer W surface, and the less the number of dressings, the smaller the estimated value of the ZDD of the wafer W surface. The dressing conditions may further include the hardness of the bristles of the brush 42. The above-mentioned correlation information may be information having a table structure.

[0055] The control unit 64 includes a CPU, and realizes various functions by the CPU executing programs stored in the storage unit 63. The control unit 64 includes an information acquisition unit 641, a dressing condition setting unit 642, a dressing control unit 643, and a polishing control unit 644. The information acquisition unit 641 and the dressing condition setting unit 642 configure a dressing condition setting device.

[0056] The information acquiring unit 641 acquires the average opening diameter of the unused polishing pad 26 based on the signal output from the code reading unit 5. The information acquiring unit 641 acquires, for example, a target value of the ZDD on the surface of the wafer W as the target shape of the wafer W set using the input unit 61. The target value of the ZDD on the surface of the wafer W may be expressed by a single numerical value or may be expressed by a numerical range. The information acquiring unit 641 may acquire the average opening diameter of the unused polishing pad 26 as follows. The one-dimensional code or two-dimensional code is configured to have pad information indicating at least one of the model and manufacturing lot of the polishing pad 26. The memory unit 63 is caused to store a plurality of pad information pieces having different contents and information for acquiring opening diameter, which associates the average opening diameter for each pad information piece. The information acquiring unit 641 may acquire the pad information corresponding to the polishing pad 26 based on the signal output from the code reading unit 5, and acquire the average opening diameter based on the information for acquiring opening diameter stored in the memory unit 63. Furthermore, the information acquisition unit 641 may acquire the average opening diameter set using the input unit 61 .

[0057] The dressing condition setting unit 642 sets dressing conditions for the unused polishing pad 26 to bring the ZDD of the wafer W surface after polishing to the target value based on the average opening diameter of the unused polishing pad 26 and the target value of the ZDD of the wafer W surface acquired by the information acquisition unit 641, and correlation information.

[0058] The dressing control unit 643 controls the dressing unit 4 so as to dress the polishing pad 26 based on the dressing conditions set by the dressing condition setting unit 642 .

[0059] The polishing control unit 644 controls the polishing unit 2 to rotate the polishing head 21 and the polishing pad 26, thereby polishing the surface W1 of the wafer W.

[0060] <Wafer manufacturing method> Next, a method for setting dressing conditions for the polishing pad 26 using the single-sided polishing apparatus 1 and a method for manufacturing the wafer W, including a method for polishing one side of the wafer W, will be described. As shown in FIG. 5, the manufacturing method of the wafer W includes a pulling-up process (step S1), a block processing process (step S2), a slicing process (step S3), a pre-processing process (step S4), a double-sided simultaneous polishing process (step S5), a single-sided finishing process (step S6) as a finishing process, a cleaning process (step S7), and a final wafer inspection process (step S8).

[0061] In the pulling process of step S1, a cylindrical silicon single crystal is pulled up from a silicon melt by the Czochralski method.

[0062] In the block processing step S2, the outer periphery of the single crystal ingot is ground, and notches are processed according to the crystal orientation. Then, the single crystal ingot is cut into a plurality of blocks, for example, by a band saw.

[0063] In the slicing process of step S3, the block is sliced ​​into a plurality of wafers W, each having a thickness of, for example, about 1 mm, by an inner diameter blade cutter or a wire saw.

[0064] In the pre-processing step S4, chamfering is performed and rough polishing (lapping) is performed with, for example, an alumina abrasive so that both surfaces of the wafer W are parallel. Then, after etching or the like is performed as necessary, a planarization process is performed to remove unevenness on the surface of the wafer W.

[0065] In the double-sided simultaneous polishing process in step S5, a mirror finish is performed to increase the flatness of the pre-treated wafer W. For example, double-sided polishing is performed using colloidal silica liquid or the like to further increase the flatness and obtain a wafer W with a predetermined flatness.

[0066] The single-sided finishing step of step S6 includes the method of the present invention for polishing a single side of a wafer W. In the single-sided finishing step, a single-sided polishing apparatus 1 is used to polish a surface W1 to be polished of the wafer W obtained in the double-sided simultaneous polishing step. By carrying out the polishing process in the single-sided finishing step, scratches and damage on the polished surface W1 of the wafer W can be removed, and at the same time, the surface roughness of the polished surface W1 can be adjusted. The single-sided finishing process will be described in detail later.

[0067] In the cleaning step S7, the wafer W obtained in the single-side finishing step is cleaned with, for example, an alkaline solution.

[0068] In the final wafer inspection process of step S8, a wafer surface inspection device or the like is used to inspect the surface particles or scratches present on the wafer W. After the necessary quality inspections are carried out, products that pass are packaged and shipped.

[0069] Next, the single-sided finishing process in step S6 will be described in detail. 6, the single-sided finishing process includes an opening diameter obtaining step (step S61), a target shape obtaining step (step S62), a dressing condition setting step (step S63), a dressing step (step S64), a wafer setting step (step S65), a polishing step (step S66), and a wafer removal step (step S67). The target shape obtaining step and the dressing condition setting step constitute a dressing condition setting method for the polishing pad 26. The target shape obtaining step, the dressing condition setting step, the dressing step, and the polishing step constitute a single-sided polishing method for the wafer W.

[0070] In the aperture diameter acquisition step of step S61, the information acquisition unit 641 of the control unit 64 acquires the average aperture diameter of an unused polishing pad 26 to be used for polishing.

[0071] In the target shape acquisition process of step S62, the information acquisition unit 641 acquires a target value of the ZDD of the surface of the wafer W as the target shape based on an input operation of the input unit 61 by an operator.

[0072] In the dressing condition setting process of step S63, the dressing condition setting unit 642 sets dressing conditions for setting the ZDD of the wafer W surface after polishing to the target value based on the average opening diameter when unused acquired in the opening diameter acquisition process, the target value of the ZDD of the wafer W surface acquired in the target shape acquisition process, and correlation information.

[0073] The dressing condition setting unit 642 dresses the polishing pad 26, whose average opening diameter when unused has been obtained, under each dressing condition represented by the correlation information, and obtains an estimated value of the ZDD of the surface, i.e., an estimated shape, when the dressed polishing pad 26 is used to polish a wafer W under the set polishing conditions. Next, the dressing condition setting unit 642 selects an estimated value having a smallest difference from a target value from the estimated values ​​of ZDD of the surface of the wafer W corresponding to each dressing condition. In other words, the dressing condition setting unit 642 selects an estimated shape of the wafer W that is closest to the target shape from the estimated shapes of the wafer W corresponding to each dressing condition. Thereafter, the dressing condition setting unit 642 sets the dressing condition corresponding to the selected estimated value of the ZDD of the surface of the wafer W as the dressing condition to be used in the dressing process.

[0074] For example, as shown in Figure 4, when the average aperture diameter when unused obtained in the aperture diameter acquisition process is H, the estimated ZDD of the wafer W surface when dressed under the first dressing condition is Z1, the estimated ZDD of the wafer W surface when dressed under the second dressing condition is Z2, and the estimated ZDD of the wafer W surface when dressed under the third dressing condition is Z3. When the target value of the ZDD on the wafer W surface is Zt, the dressing condition setting unit 642 selects the estimated value Z2 having the smallest difference from the target value Zt from among the estimated values ​​Z1 to Z3 of the ZDD on the wafer W surface corresponding to the first to third dressing conditions, and sets the second dressing condition corresponding to the estimated value Z2 as the dressing condition to be used in the dressing process.

[0075] In the dressing step of step S64, the dressing control unit 643 controls the position adjustment unit 43 and the platen driving unit 27 of the dressing unit 4 based on the dressing conditions set in the dressing condition setting step to dress the polishing pad . This dressing process provides a polishing pad 26 that can reduce the absolute value of the difference between the ZDD of the surface of a wafer W polished under set polishing conditions and the target value to a predetermined value or less, regardless of the size of the average opening diameter when unused.

[0076] In a wafer setting step S65, the wafer W obtained in the double-sided simultaneous polishing step is set in the single-sided polishing apparatus 1.

[0077] In the polishing process of step S66, the polishing control unit 644 controls the head lifting unit 23, head driving unit 24, platen driving unit 27, wafer pressure adjustment unit 28 and polishing liquid supply unit 29 of the polishing unit 2 based on the set polishing conditions, to polish the wafer W using the polishing pad 26 dressed in the dressing process. This polishing process produces a wafer W whose absolute value of the difference between the ZDD of the wafer W surface and the target value is equal to or less than a predetermined value, that is, a wafer W having a shape that is the same as or close to the target shape.

[0078] In a wafer removal step of step S67, the wafer W is removed from the single-sided polishing apparatus 1. The removed wafer W is cleaned in a cleaning step of step S7.

[0079] <Effects of the embodiment> The method for setting dressing conditions for the polishing pad 26 includes an aperture diameter acquisition step for acquiring an average aperture diameter on the pad surface 261 of the polishing pad 26, a target shape acquisition step for acquiring a target value of the ZDD of the surface of the wafer W after polishing, and a dressing condition setting step for setting dressing conditions. The dressing condition setting step sets dressing conditions for the polishing pad to set the ZDD of the wafer W after polishing to the target value, based on correlation information representing a correlation between the average aperture diameter of an unused polishing pad 26, the dressing conditions, and an estimated value of the ZDD of the surface of the wafer W polished under the set polishing conditions by the polishing pad 26 dressed under the dressing conditions, the average aperture diameter of the polishing pad 26 acquired in the aperture diameter acquisition step, and the target value of the ZDD of the surface of the wafer W acquired in the target shape acquisition step. Therefore, even if the average opening diameter varies for each polishing pad 26, by dressing the polishing pad 26 under the dressing conditions set based on the correlation information, it is possible to obtain a wafer W having a desired shape in which the absolute value of the difference between the ZDD of the wafer W surface and the target value is equal to or less than a predetermined value without adjusting the set polishing conditions. In addition, since a wafer W having a desired shape can be obtained, the yield of the wafer W is improved, and it is possible to improve energy efficiency, improve production efficiency, and reduce waste.

[0080] The correlation information indicates a correlation between the average opening diameter of an unused polishing pad 26, a plurality of different dressing conditions, and an estimated value of the ZDD of the surface of the wafer W polished by the polishing pad 26 dressed under each of the plurality of dressing conditions. The dressing condition setting step obtains an estimated value of the ZDD of the surface of the wafer W when the polishing pad 26 is dressed under each of the plurality of dressing conditions based on the correlation information, selects an estimated value of the ZDD having the smallest difference from a target value from the obtained estimated values ​​of the ZDD, and sets the dressing condition corresponding to the selected estimated value as the dressing condition to be used in the dressing step. Therefore, an appropriate dressing condition can be set by a simple method of selecting one dressing condition from a plurality of dressing conditions prepared in advance based on the correlation information.

[0081] As a method for adjusting the average opening diameter by dressing the polishing pad 26, a method is used in which the suede-type polishing pad 26 is rotated while the brush 42 is moved relative to the polishing pad 26. Therefore, the average opening diameter can be adjusted by the simple method of simply rotating the polishing pad 26 with the brush 42. In particular, by adjusting the suede-type polishing pad 26 using the brush 42 whose bristles deform, rather than using a grindstone to scrape the polishing pad 26, the average opening diameter can be finely adjusted without substantially changing the thickness of the polishing pad 26. Furthermore, when dressing the polishing pad 26 using a grindstone, there is a risk that components of the grindstone will adhere to the polishing pad 26, causing a deterioration in LPD (Light Point Defect), but by using the brush 42, the deterioration of LPD can be suppressed.

[0082] In the dressing condition setting step, the polishing pad 26 is rotated while the brush 42 is moved from the center to the outer periphery of the pad surface 261, thereby dressing the spiral dressing region 261A. Therefore, even if a brush 42 having a small contact area with the pad surface 261 is used, the average opening diameter of the polishing pad 26 can be appropriately adjusted by simply controlling the rotation of the polishing pad 26 and the movement of the brush 42.

[0083] The dressing condition setting process sets dressing conditions in which at least one of the brush pressure amount and the number of dressing times is different depending on at least one of the average opening diameter acquired in the opening diameter acquisition process and the target value of the ZDD of the wafer W surface acquired in the target shape acquisition process. Therefore, the dressing conditions can be appropriately adjusted by a simple method of simply adjusting at least one of the brush pressure amount and the number of dressing times in accordance with a set value.

[0084] [Variations] Although an embodiment of the present invention has been described in detail above with reference to the drawings, the specific configuration is not limited to this embodiment, and various improvements and design changes that do not deviate from the gist of the present invention are also included in the present invention.

[0085] For example, a single-sided polishing method similar to the single-sided polishing method of the above embodiment may be used to manage the ESFQD as the target shape of the wafer W. In this case, the correlation between the average opening diameter when unused and the ESFQD after single-sided polishing using an unused polishing pad 26 dressed under standard dressing conditions is such that, if the polishing conditions are the same, the larger the average opening diameter when unused, the larger the ESFQD. In other words, the correlation between the average opening diameter when unused and the ESFQD is the same as that of the ZDD on the surface of the wafer W, and can be expressed by a linear equation. Although the dressing conditions are set based on the average opening diameter of the numerous pores on the pad surface 261, the dressing conditions may be set based on the median, maximum or minimum opening diameter of the numerous pores.

[0086] As correlation information, a formula showing the correlation between the average opening diameter of an unused polishing pad 26, the dressing conditions, and the ZDD of the surface of the wafer W polished by the polishing pad 26 dressed under the dressing conditions may be applied, and in the dressing condition setting process, the dressing conditions may be set by substituting the average opening diameter of the polishing pad 26 acquired in the opening diameter acquisition process and the target value of the ZDD of the surface of the wafer W acquired in the target shape acquisition process into the formula.

[0087] When dressing the polishing pad 26, the brush 42 may be moved without rotating the polishing pad 26. As a method for adjusting the brush pressing amount, a method in which the height position of the polishing pad 26 is fixed and the height position of the brush 42 is adjusted has been exemplified, but the height position of the polishing pad 26 may be changed while fixing the height position of the brush 42 or while changing the height position of the brush 42.

[0088] The dressing condition setting step may set dressing conditions that vary the workload of the brush 42 on the polishing pad 26 according to at least one of the average opening diameter acquired in the opening diameter acquisition step and the target value of the ZDD of the surface of the wafer W acquired in the target shape acquisition step. Examples of a method for varying the workload of the brush 42 on the polishing pad 26 include the following methods 1 to 4. ·Method 1 A method of varying the contact time between the brush 42 and the polishing pad 26 by varying at least one of the rotation speed of the polishing pad 26 and the movement speed of the brush 42. ·Method 2 A method of varying the length of the bristles of the brush 42 (for example, when the bristles are long, the bristles are curved compared to when the bristles are short, so the pressing force of the bristles against the polishing pad 26 is reduced, and the amount of work is reduced) ·Method 3 A method of varying the shape of the tips of the bristles of the brush 42 (for example, when the tips of the bristles are sharp, pressure is concentrated at the tips of the bristles compared to when the tips are not sharp, or the amount of scratching work caused by the curling of the bristles is concentrated at the tips of the bristles, increasing the amount of work). ·Method 4 The diameter of the bristles of the brush 42 (for example, if the bristles have a large diameter, they will press against the polishing pad 26 with a larger force than if the bristles had a small diameter, resulting in an increased amount of work). The pressing force P (N) of the brush 42 can be expressed by the following formula (1). P=fnEd 4 / 6.79L 3 … (1) f: Displacement (m) of the holding arm 412 when the brush 42 is pressed against the polishing pad 26 n: number of hairs E: Elastic modulus of hair (Pa) d: Hair diameter (m) L: Hair length (m) EXAMPLES

[0089] Next, examples of the present invention will be described, but the present invention is not limited to the examples.

[0090] [Example 1: Correlation between average aperture ratio when unused and ZDD on wafer surface] First, the single-sided polishing apparatus 1 of the above embodiment was prepared. In addition, a plurality of suede-type polishing pads 26 of the same model but different production lots were prepared for each production lot. The average opening diameter of the plurality of polishing pads 26 when unused was the same for each production lot. A polishing pad 26 and a brush 42 made of nylon with bristles of 5 mm in length were attached to the single-sided polishing device 1. The height position of the brush 42 was adjusted so that the brush pressing amount was 3.7 mm. The brush pressing amount was 0 mm when the tips of the bristles were in contact with the polishing pad 26 without bending the bristles.

[0091] As in the dressing step of step S64, the position adjustment unit 43 and the platen driving unit 27 of the dressing unit 4 were controlled to dress the polishing pad 26 140 times. As in the polishing process of step S66, the head lifting unit 23, head driving unit 24, platen driving unit 27, wafer pressure adjusting unit 28 and polishing liquid supply unit 29 were controlled based on the set polishing conditions to polish the wafer W. The ZDD of the wafer W surface (polished surface) after polishing was measured.

[0092] Dressing was performed 140 times for each of the polishing pads 26 under the above-mentioned conditions, and after polishing the wafer W with each polishing pad 26, the ZDD of the surface of the wafer W was measured. For each production lot, the average value of the ZDD of the surface of the wafer W polished using each polishing pad 26 was calculated. The relationship between the average opening diameter when unused and the average value of the calculated ZDD of the surface of the wafer W is shown in FIG. As shown in Fig. 7, it was confirmed that, if the dressing and polishing conditions were the same, the larger the average aperture diameter when unused, the larger the ZDD on the surface of the wafer W. It was confirmed that the correlation between the average aperture diameter when unused and the ZDD on the surface of the wafer W can be expressed by a linear approximation, and that there is a proportional relationship.

[0093] [Example 2: Correlation between brush pressure and ZDD and ESFQD on wafer surface] First, three suede-type polishing pads 26 having the same average opening diameter and model when unused were prepared. A polishing pad 26 and the same brush 42 as in Example 1 were attached to the same single-sided polishing apparatus 1 as in Example 1. The height position of the brush 42 was adjusted so that the brush pressing amount was 3.3 mm, and the polishing pad 26 was dressed 140 times in the same manner as in Example 1 to obtain the polishing pad 26 of Example 2-1. The polishing pad 26 of Example 2-2 was obtained by dressing an undressed polishing pad 26 under the same conditions as Example 2-1, except that the height position of the brush 42 was adjusted so that the brush pressing amount was 3.7 mm. The polishing pad 26 of Example 2-3 was obtained by dressing an undressed polishing pad 26 under the same conditions as Example 2-1, except that the height position of the brush 42 was adjusted so that the brush pressing amount was 3.9 mm.

[0094] Using the polishing pads 26 of Examples 2-1 to 2-3, a wafer W was polished under the same set polishing conditions as in Example 1, and then the ZDD and ESFQD of the surface of the wafer W were measured. The relationship between the brush pressing amount and the ZDD of the surface of the wafer W is shown in Figure 8. The relationship between the brush pressing amount and the ESFQD is shown in Figure 9.

[0095] As shown in Figures 8 and 9, it was confirmed that, when the average opening diameter and polishing conditions when unused were the same, the ZDD and ESFQD on the wafer W surface increased with an increase in the brush pressure.

[0096] [Example 3: Correlation between brush pressure and ESFQD] First, two suede-type polishing pads 26 of the same model, each having an average opening diameter of 60.3 μm, 62.6 μm, and 67.0 μm when unused, were prepared. A polishing pad 26 having an average opening diameter of 60.3 μm when unused and a brush 42 the same as in Examples 1 and 2 were attached to the same single-sided polishing apparatus 1 as in Examples 1 and 2. The height position of the brush 42 was adjusted so that the brush pressing amount was 3.5 mm, and the polishing pad 26 was dressed 140 times in the same manner as in Examples 1 and 2 to obtain a polishing pad 26 of Comparative Example 3-1. An unused polishing pad 26 having an average opening diameter of 62.6 μm that had not been dressed was dressed under the same conditions as the polishing pad 26 of Comparative Example 3-1 to obtain the polishing pad 26 of Comparative Example 3-2. An unused polishing pad 26 having an average opening diameter of 67.0 μm that had not been dressed was dressed under the same conditions as the polishing pad 26 of Comparative Example 3-1 to obtain the polishing pad 26 of Comparative Example 3-3.

[0097] An unused polishing pad 26 having an average opening diameter of 60.3 μm and not having been dressed was dressed under the same conditions as in Comparative Example 3-1, except that the height position of the brush 42 was adjusted so that the brush pressing amount was 3.9 mm, to obtain the polishing pad 26 of Example 3-1. The polishing pad 26 of Example 3-2 was obtained by dressing the polishing pad 26 of Example 3-2 under the same conditions as those of Example 3-1, except that the height position of the brush 42 was adjusted so that the brush pressing amount was 3.5 mm, and the polishing pad 26 of Example 3-2 was dressed under the same conditions as those of the polishing pad 26 of Comparative Example 3-2. An unused polishing pad 26 having an average opening diameter of 67.0 μm and not having been dressed was dressed under the same conditions as in Example 3-1, except that the height position of the brush 42 was adjusted so that the brush pressure was 3.14 mm, to obtain the polishing pad 26 of Example 3-3. The brush pressure of the polishing pad 26 in Examples 3-1 to 3-3 was set so that the target value of the ZDD on the surface when the wafer W was polished under the same set polishing conditions as in Example 1 was −29.50 nm / mm 2 , the size when the target value of ESFQD is −0.0230 μm.

[0098] The polishing pads 26 of Comparative Examples 3-1 to 3-3 and the polishing pads 26 of Examples 3-1 to 3-3 were used to polish a wafer W under the same set polishing conditions as in Example 1, and then the ZDD and ESFQD of the surface of the wafer W were measured. The relationship between the average opening diameter, the brush pressing amount, and the ZDD of the surface of the wafer W when unused is shown in Fig. 10. The relationship between the average opening diameter, the brush pressing amount, and the ESFQD when unused is shown in Fig. 11.

[0099] As shown in Figures 10 and 11, in Comparative Examples 3-1 to 3-3, in which the dressing conditions were the same regardless of the average opening diameter when unused, it was confirmed that, if the polishing conditions were the same, the larger the average opening diameter when unused, the larger the ZDD and ESFQD on the wafer W surface. On the other hand, in Examples 3-1 to 3-3 in which the dressing conditions differ depending on the average opening diameter when unused, it was confirmed that if the polishing conditions were the same, the ZDD and ESFQD on the wafer W surface were almost equal and close to the target values, regardless of the average opening diameter when unused. In particular, when comparing the absolute values ​​of the difference from the target value of ZDD on the wafer W surface, Comparative Examples 3-1 and 3-3 were 1.38 nm / mm 2 , 1.11nm / mm 2 In contrast, in Examples 3-1 and 3-3, the average particle diameter was 0.04 nm / mm 2 , 0.16nm / mm 2 In addition, when comparing the absolute values ​​of the difference from the target value of ESFQD, the absolute values ​​were 0.0013 μm and 0.0017 μm in Comparative Examples 3-1 and 3-3, respectively, whereas the absolute values ​​were 0.0002 μm and 0.0006 μm in Examples 3-1 and 3-3, respectively. From these facts, it was confirmed that a wafer W having a desired shape can be obtained by adjusting the dressing conditions according to the average opening diameter when unused. [Industrial Applicability]

[0100] According to the polishing pad dressing condition setting method, single-sided wafer polishing method, wafer manufacturing method, polishing pad dressing condition setting device, and single-sided wafer polishing device of the present invention, wafers of the desired shape can be obtained, thereby improving wafer yield, improving energy efficiency, improving production efficiency, and reducing waste. [Explanation of symbols]

[0101] 1...single-sided polishing apparatus, 4...dressing unit, 21...polishing head, 24...head driving unit (rotation driving unit), 26...polishing pad, 27...plate driving unit (rotation driving unit), 42...brush, 43...position adjustment unit, 64...control unit, 641...information acquisition unit (dressing condition setting device), 642...dressing condition setting unit (dressing condition setting device), 643...dressing control unit, 644...polishing control unit, W...wafer.

Claims

1. A method for setting dressing conditions for a suede-type polishing pad used for single-sided polishing of a wafer, comprising: an aperture diameter acquisition step of acquiring an aperture diameter of a hole on a surface of the polishing pad; a target shape acquisition step of acquiring a target shape of the wafer after polishing; and a dressing condition setting step of setting dressing conditions for the polishing pad based on the correlation information, the correlation information represents a correlation between the opening diameter of the polishing pad, a dressing condition, and an estimated shape of the wafer polished by the polishing pad dressed under the dressing condition; A method for setting dressing conditions for a polishing pad, the dressing condition setting process setting the dressing conditions for making the shape of the wafer after polishing the target shape based on the correlation information, the opening diameter acquired in the opening diameter acquisition process, and the target shape acquired in the target shape acquisition process.

2. 2. The method for setting dressing conditions for a polishing pad according to claim 1, the correlation information represents a correlation between the opening diameter of the polishing pad, a plurality of different dressing conditions, and an estimated shape of the wafer polished by the polishing pad dressed under each of the plurality of dressing conditions; The dressing condition setting step includes: determining an estimated shape of the wafer when the polishing pad, whose opening diameter has been acquired in the opening diameter acquisition step, is dressed under each of the plurality of dressing conditions based on the correlation information; Select the estimated shape that is closest to the target shape from the estimated shapes obtained; A method for setting dressing conditions for a polishing pad, the dressing conditions corresponding to the selected estimated shape being set as dressing conditions for making the shape of the wafer after polishing into the target shape.

3. A method for polishing a single side of a wafer, comprising the steps of: pressing a wafer against a suede-type polishing pad that is larger than the wafer; and rotating the wafer and the polishing pad to polish the wafer, the method comprising the steps of: A step of setting a dressing condition for the polishing pad by the method for setting a dressing condition for the polishing pad according to claim 1 or 2; a dressing step of dressing the polishing pad under the dressing conditions; a polishing step of polishing the wafer with the dressed polishing pad.

4. 4. The method for polishing a single side of a wafer according to claim 3, The method for polishing one side of a wafer, wherein the dressing step dresses the polishing pad by moving at least one of the brush and the polishing pad while pressing the brush against the polishing pad.

5. 5. The method for polishing a single side of a wafer according to claim 4, A method for polishing one side of a wafer, wherein the dressing step dresses the polishing pad by rotating the polishing pad and moving the brush from the center to the outer periphery of the polishing pad, or from the outer periphery to the center.

6. 5. The method for polishing a single side of a wafer according to claim 4, A method for polishing one side of a wafer, wherein the dressing condition setting process sets the dressing conditions such that at least one of the amount of pressing of the brush against the polishing pad and the number of dressing times is different depending on at least one of the opening diameter of the polishing pad acquired in the opening diameter acquisition process and the target shape of the wafer acquired in the target shape acquisition process.

7. A method for manufacturing a wafer, comprising the steps of: A finishing step of finishing the wafer is provided, A method for manufacturing a wafer, wherein in the finishing step, the wafer is polished by the method for polishing a single side of a wafer according to claim 3.

8. A dressing condition setting device for a suede-type polishing pad used for single-sided polishing of a wafer, comprising: an information acquiring unit that acquires an opening diameter of a hole in a surface of the polishing pad and a target shape of the wafer after polishing; a dressing condition setting unit that sets dressing conditions for the polishing pad based on correlation information; the correlation information represents a correlation between the opening diameter of the polishing pad, a dressing condition, and an estimated shape of the wafer polished by the polishing pad dressed under the dressing condition; A polishing pad dressing condition setting device, wherein the dressing condition setting unit sets the dressing conditions for making the shape of the wafer after polishing the target shape based on the correlation information and the opening diameter and the target shape acquired by the information acquisition unit.

9. 9. The polishing pad dressing condition setting device according to claim 8, the correlation information represents a correlation between the opening diameter of the polishing pad, a plurality of different dressing conditions, and an estimated shape of a wafer polished by the polishing pad dressed under each of the plurality of dressing conditions; The dressing condition setting unit includes: determining an estimated shape of the wafer when the polishing pad, the opening diameter of which has been acquired by the information acquiring unit, is dressed under each of the plurality of dressing conditions based on the correlation information; Select the estimated shape that is closest to the target shape from the estimated shapes obtained; a dressing condition setting device for a polishing pad that sets the dressing condition corresponding to the selected estimated shape as a dressing condition for making the shape of the wafer after polishing into the target shape;

10. A single-sided polishing apparatus for polishing a wafer by pressing a wafer held by a polishing head against a suede-type polishing pad larger than the wafer and rotating the polishing head and the polishing pad, comprising: a dressing unit for dressing the polishing pad; a rotation drive unit that rotates the polishing head and the polishing pad; 10. A dressing condition setting device according to claim 8 or claim 9, which sets dressing conditions for the polishing pad; a dressing control unit that controls the dressing unit to dress the polishing pad under the dressing conditions; a polishing control unit that controls the rotation drive unit to polish the wafer with the dressed polishing pad.

11. 11. The apparatus for polishing a single side of a wafer according to claim 10, A single-sided polishing apparatus for wafers, wherein the dressing control unit controls the dressing unit to dress the polishing pad by pressing a brush against the polishing pad and moving at least one of the brush and the polishing pad.

12. 12. The apparatus for polishing a single side of a wafer according to claim 11, The dressing control unit controls the dressing unit to dress the polishing pad by rotating the polishing pad and moving the brush from the center to the outer periphery of the polishing pad, or from the outer periphery to the center, in a single-sided polishing apparatus for wafers.

13. 12. The apparatus for polishing a single side of a wafer according to claim 11, A single-sided polishing apparatus for a wafer, wherein the dressing condition setting unit sets the dressing conditions in which at least one of the amount of pressing of the brush against the polishing pad and the number of dressings is different depending on at least one of the opening diameter of the polishing pad and the target shape of the wafer acquired by the information acquisition unit.

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