Manufacturing method for semiconductor devices

Abstract

To provide a manufacturing method of a semiconductor device, capable of suppressing a cut dust generated at the time of cutting of an adhesive tape for a semiconductor processing.SOLUTION: A method includes in this order, following steps S1, S2. The step S1 is: a step for sticking an adhesive tape for semiconductor processing to a surface of a semiconductor wafer which has, front and rear surfaces on which a circuit is formed, then, cutting the adhesive tape for semiconductor processing by a blade along a contour of the semiconductor wafer, then removing a non-sticking part which is not stuck to the semiconductor wafer on the adhesive tape for semiconductor processing, the step S2 is: a step for grinding a rear surface of the semiconductor wafer. In addition, in the step S1, in a vertical direction to a horizontal surface of the adhesive tape for semiconductor processing stuck to the semiconductor wafer, a sticking surface side with the semiconductor wafer of the adhesive tape for semiconductor processing is a lower direction, and an opposite side is an upper direction, and in this state, a cut edge of the non-sticking part is warped in the upper direction, by advance of the blade.SELECTED DRAWING: Figure 1

Description

[[Technical Field]]

[0001] The present invention relates to a method for manufacturing a semiconductor device. More specifically, the present invention relates to a method for manufacturing a semiconductor device using an adhesive tape for semiconductor processing. [[Background Art]]

[0002] In recent years, along with the rapid progress of miniaturization and multi-functionalization of various electronic devices, there has been a demand for smaller and thinner semiconductor chips mounted on various electronic devices. Thinning of semiconductor chips is generally performed by grinding the back surface of a semiconductor wafer. Further, as a method for obtaining thinned semiconductor chips, a method called dicing before grinding (DBG) is known. In DBG, after forming grooves of a predetermined depth from the front surface side (circuit forming surface side) of a semiconductor wafer using a dicing blade or the like, grinding is performed from the back surface side of the semiconductor wafer, and the semiconductor wafer is singulated by the grinding to obtain semiconductor chips. It is this method. In DBG, back grinding of the semiconductor wafer and singulation of the semiconductor wafer can be performed simultaneously, so thinned semiconductor chips can be efficiently manufactured.

[0003] Further, as a modification of DBG, a method has been proposed in which a modified region is formed inside the semiconductor wafer by laser, plasma or the like without forming grooves on the front surface side of the semiconductor wafer, and the semiconductor wafer is singulated by stress or the like during back grinding of the semiconductor wafer to obtain semiconductor chips. In the case of this method, the semiconductor wafer is cut along the crystal direction starting from the modified region. Therefore, the occurrence of chipping can be reduced compared to DBG using a dicing blade. As a result, a semiconductor chip excellent in bending strength can be obtained, and further thinning of the semiconductor chip is possible. In addition, compared with DBG in which grooves of a predetermined depth are formed on the surface of the semiconductor wafer by a dicing blade or the like, there is no region where the semiconductor wafer is scraped off by the dicing blade (in other words, the kerf width is extremely small), so there is also an advantage that the yield of semiconductor chips is excellent.

[0004] Incidentally, when manufacturing semiconductor chips that include a back grinding process of semiconductor wafers, such as DBG or a modified DBG method, it is common practice to attach a semiconductor processing adhesive tape called a back grind sheet to the surface of the semiconductor wafer in order to protect the circuits on the surface of the semiconductor wafer and to hold the semiconductor wafer and semiconductor chip in place. Such adhesive tapes for semiconductor processing include, for example, adhesive tapes for semiconductor processing in which a substrate and an adhesive layer are laminated. More recently, adhesive tapes for semiconductor processing having a laminated structure in which a buffer layer, a substrate, and an adhesive layer are laminated in that order have also been proposed in order to alleviate stress during back grinding of semiconductor wafers and prevent cracking and chipping of semiconductor wafers (see, for example, Patent Document 1). [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2015-183008 [Overview of the project] [Problems that the invention aims to solve]

[0006] Incidentally, during the manufacturing of semiconductor chips, which includes a backside grinding process for semiconductor wafers such as DBG or a modified DBG method, if there is excess semiconductor processing adhesive tape on the outer edge of the semiconductor wafer when the backside of the semiconductor wafer is ground with a grinder, the grinder may catch on the excess semiconductor processing adhesive tape. Therefore, the semiconductor processing adhesive tape is cut along the outer shape of the semiconductor wafer before backside grinding.

[0007] However, with the miniaturization and thinning of semiconductor chips, cut dust generated during the cutting of adhesive tape used for semiconductor processing can cause chipping or damage to the semiconductor chip (hereinafter referred to as "semiconductor chip cracks"). Therefore, there is a need to suppress the generation of cut dust, which is a cause of semiconductor chip cracks.

[0008] Therefore, the object of the present invention is to provide a method for manufacturing a semiconductor device that can suppress cut dust generated when cutting adhesive tape for semiconductor processing. [Means for solving the problem]

[0009] As a result of diligent research, the inventors have found that the above problem can be solved by satisfying certain specific conditions when cutting a semiconductor processing adhesive tape attached to the surface of a semiconductor wafer along the outer shape of the semiconductor wafer.

[0010] In other words, the present invention relates to the following [1] to [7]. [1] The following steps (S1) and (S2) are included in this order: Step (S1): After applying semiconductor processing adhesive tape to the surface of a semiconductor wafer having a surface and a back surface on which circuits are formed, the semiconductor processing adhesive tape is cut with a blade along the outer shape of the semiconductor wafer, and the non-adhesive portion of the semiconductor processing adhesive tape that is not attached to the semiconductor wafer is removed. • Process (S2): A process of grinding the back surface of the semiconductor wafer. A method for manufacturing a semiconductor device, wherein in step (S1), when the back side of the semiconductor wafer is considered to be downwards and the front side of the semiconductor wafer is considered upwards in the direction perpendicular to the horizontal plane of the semiconductor wafer, the blade is advanced such that the cutting edge of the non-adhesive portion curves upwards. [2] The method for manufacturing a semiconductor device according to [1] above, wherein the following condition (α1) is satisfied when the blade is advanced in step (S1). Condition (α1): Adjust the angle of the A-axis of the cutting edge of the blade to less than 0°. [3] A method for manufacturing a semiconductor device as described in [2] above, which also satisfies the following condition (α2). Condition (α2): Adjust the angle of the B axis of the blade to 0° or greater, and adjust the angle of the C axis of the blade to 0° or greater. [4] A method for manufacturing a semiconductor device according to [1] above, wherein the following condition (β1) is satisfied when the blade is advanced in step (S1). Condition (β1): The angle of the B axis of the blade is adjusted to be greater than 0° and less than +45°, and the angle of the C axis of the blade is greater than 0° and less than +30° ° Adjust to less than. [5] In the method for manufacturing a semiconductor device described in any of [1] to [4] above, Furthermore, a method for manufacturing a semiconductor device, including the following step (S3). • Process (S3): Process of dicing the semiconductor wafer to form individual pieces. [6] In the method for manufacturing a semiconductor device described in any of [1] to [4] above, As the semiconductor wafer, a semiconductor wafer having grooves formed on its surface is used. A manufacturing method comprising the above step (S2), wherein the semiconductor wafer is divided into a plurality of chips starting from the grooves. [7] In the method for manufacturing a semiconductor device described in any of [1] to [4] above, As the semiconductor wafer, a semiconductor wafer in which a modified region is formed internally is used, or a modified region is formed internally of the semiconductor wafer after the above step (S1). A manufacturing method comprising the above step (S2), wherein the semiconductor wafer is divided into a plurality of chips starting from the modified region. [Effects of the Invention]

[0011] According to the present invention, it is possible to provide a method for manufacturing a semiconductor device that can suppress cut dust generated when cutting adhesive tape for semiconductor processing. [Brief explanation of the drawing]

[0012] [Figure 1] This figure shows an embodiment of step (S1) of the semiconductor device manufacturing method of the present invention. [Figure 2] This is a schematic diagram showing an example of an adhesive tape application apparatus for applying adhesive tape for semiconductor processing to semiconductor wafers. [Figure 3] It is an explanatory diagram of the blade portion. [Figure 4] It is a schematic explanatory diagram relating to the definition of the A-axis. [Figure 5] It is a schematic explanatory diagram showing a modified example of the blade shape with respect to the A-axis. [Figure 6] It is a schematic explanatory diagram relating to the definition of the B-axis. [Figure 7] It is a schematic explanatory diagram showing a modified example of the blade shape with respect to the B-axis. [Figure 8] It is a schematic explanatory diagram relating to the definition of the C-axis. [Figure 9] It is a diagram showing an analysis model by Abaqus. [Figure 10] It is a diagram showing details of the dimensions of the blade used in the example. [Figure 11] These are analysis images by Abaqus of Example II-3sim. and Comparative Example II-2sim. in "Evaluation of cutting performance by blade (2): Evaluation by simulation". [Figure 12] These are scanning electron microscope (SEM) observation results (substitute drawings for photographs) of cross sections of Example II-3exp. and Comparative Example II-2exp. in "Evaluation of cutting performance by blade (4): Evaluation by experiment". MODE FOR CARRYING OUT THE INVENTION

[0013] The upper limit values and lower limit values of the numerical ranges described in the present specification can be arbitrarily combined. For example, when "A to B" and "C to D" are described as numerical ranges, the numerical ranges of "A to D" and "C to B" are also included in the scope of the present invention. Unless otherwise specified, the numerical range "lower limit value to upper limit value" described in the present specification means not less than the lower limit value and not more than the upper limit value. In the present specification, the numerical values in the examples are numerical values that can be used as an upper limit value or a lower limit value.

[0014] Furthermore, in this specification, when directions such as up, down, left, right, or front and back are indicated without providing a reference figure, the up, down, left, and right directions are parallel to the plane of the paper, and the front and back directions are perpendicular to the plane of the paper.

[0015] [Aspects of manufacturing a semiconductor device] The present invention's method for manufacturing a semiconductor device (hereinafter also referred to as "this manufacturing method") includes the following steps (S1) and (S2) in this order. Step (S1): After applying semiconductor processing adhesive tape to the surface of a semiconductor wafer having a surface and a back surface on which circuits are formed, the semiconductor processing adhesive tape is cut with a blade along the outer shape of the semiconductor wafer, and the non-adhesive portion of the semiconductor processing adhesive tape that is not attached to the semiconductor wafer is removed. • Process (S2): A process of grinding the back surface of the semiconductor wafer. Furthermore, in this manufacturing method, in step (S1), when the back side of the semiconductor wafer is considered to be downwards and the front side of the semiconductor wafer is considered upwards in the direction perpendicular to the horizontal plane of the semiconductor wafer, the blade is advanced such that the cut edge of the non-adhesive portion curves upwards. Note that no circuits are formed on the back surface of the semiconductor wafer.

[0016] An embodiment of process (S1) in this manufacturing method is shown in Figure 1. Figure 1(A) is a perspective view showing an embodiment of process (S1), and Figure 1(B) is a cross-sectional view showing an embodiment of process (S1). Note that the laminated structure of the semiconductor processing adhesive tape AS is omitted from the illustration in Figure 1. Also, in the illustrations used in the following description, including Figure 1, key parts may be enlarged for convenience in order to make the features of the present invention easier to understand. Therefore, the dimensional ratios of each component may not be the same as in reality.

[0017] As shown in Figure 1, in step (S1), when cutting the semiconductor processing adhesive tape AS along the outer shape of the semiconductor wafer WF with a blade 56, the blade 56 is advanced such that the cut edge AS1a of the non-adherent portion AS1 of the semiconductor processing adhesive tape AS is curved upward when the back side of the semiconductor wafer WF is considered downward and the front side of the semiconductor wafer WF (the side attached to the semiconductor processing adhesive tape AS) is considered upward in the direction perpendicular to the horizontal plane of the semiconductor wafer WF. In this way, the inventors have found that by advancing the blade 56 such that the cut edge AS1a of the non-adherent portion AS1 of the semiconductor processing adhesive tape AS to the semiconductor wafer WF curves upward, the cut surface of the semiconductor processing adhesive tape AS is not roughened during cutting by the blade 56, resulting in good cutting performance and suppression of cut dust generation. Furthermore, if the blade 56 is advanced such that the cut edge AS1a of the non-adherent portion AS1 of the semiconductor processing adhesive tape AS to the semiconductor wafer WF sinks downward, the cut surface of the semiconductor processing adhesive tape AS becomes rough when cut by the blade 56, making it impossible to suppress the generation of cut dust.

[0018] The following describes in detail steps (S1) and (S2) of this manufacturing method, including specific methods for advancing the blade so that the cut edge of the non-adhered portion of the semiconductor processing adhesive tape curves upward. In the following description, "semiconductor processing adhesive tape" will also be simply referred to as "adhesive tape."

[0019] [Process (S1)] In step (S1), a semiconductor processing adhesive tape is applied to the surface of a semiconductor wafer having a front surface and a back surface on which circuits are formed. Then, the semiconductor processing adhesive tape is cut with a blade along the outer shape of the semiconductor wafer, and the non-adhesive portion of the semiconductor processing adhesive tape that is not attached to the semiconductor wafer is removed.

[0020] Step (S1) is performed, for example, using the adhesive tape application device 1 shown in Figure 2. The adhesive tape application apparatus 1 shown in Figure 2 comprises a supply means 2 for supplying a strip-shaped adhesive tape AS, a support means 3 for supporting a semiconductor wafer WF, a pressing means 4 for pressing and applying the adhesive tape AS to the semiconductor wafer WF, a cutting means 5 for cutting the adhesive tape AS into a predetermined shape, a removal means 6 for removing the unnecessary portion (non-adherent portion with the semiconductor wafer WF) AS1 from which the adhesive portion to be attached to the semiconductor wafer WF has been cut out, and a recovery means 7 for recovering the unnecessary portion AS1. In Figure 2, the semiconductor wafer WF is placed on the XY plane. Furthermore, the vertical movement of the blade 56 provided in the cutting means 5 is performed along the Z axis.

[0021] The supply means 2 includes a support roller 21 for winding and supporting the adhesive tape AS, a guide roller 22 for guiding the adhesive tape AS pulled out from the support roller 21, a drive roller 24 driven by a rotary motor 23 as a drive device to feed out the adhesive tape AS, and a pinch roller 25 that sandwiches the adhesive tape AS between itself and the drive roller 24.

[0022] The support means 3 comprises a linear motor 33, which serves as a drive device, housed in a recess 32 of the outer table 31, and an inner table 35 supported by the output shaft 34 of the linear motor 33. The upper surface of the inner table 35 is a support surface 36, and the upper surface of the outer table 31 is an upper surface 37 parallel to the support surface 36.

[0023] The pressing means 4 includes a linear motor 41 as a drive device, a linear motor 43 as a drive device supported by a slider 42 of the linear motor 41, a bracket 45 supported by the output shaft 44 of the linear motor 43, and a pressing roller 46 rotatably supported by the bracket 45 and having a length greater than or equal to the diameter of the semiconductor wafer WF.

[0024] The cutting means 5 includes a linear motor 51 as a drive device, a rotary motor 53 as a drive device supported on the output shaft 52 of the linear motor 51, a bracket 55 supported on the output shaft 54 ​​of the rotary motor 53, and a blade 56 provided at the tip of the bracket 55.

[0025] The removal means 6 includes a rotating motor 62 as a drive device supported by a slider 61 of a linear motor 41, a drive roller 63 driven by the rotating motor 62, and a pinch roller 64 that sandwiches the unwanted part AS1 between the drive roller 63.

[0026] The recovery means 7 includes a plurality of winding means 70 (first and second winding means 70A, 70B) for winding up the unwanted portion AS1, an arm 74 that supports the plurality of winding means 70 and is rotatably supported by the output shaft 73 of a rotary motor 72 which is a drive device, an unwanted portion cutting means 77 for cutting the unwanted portion AS1 being wound up by one of the winding means 70 (first winding means 70A), and a winding means 78 for winding the tip portion AS11 cut by the unwanted sheet cutting means 77 onto another winding means 70 (second winding means 70B). The first winding means 70A includes a first winding member 71A (winding member 70) for winding up the unwanted portion AS1, and a first support shaft 76A (support shaft 76) which is rotatably supported at one end of the arm 74 by the output shaft (not shown) of a first rotary motor 75A (rotating motor 75) which is a drive device. The second winding means 70B is supported at the other end of the arm 74 and employs a structure substantially the same as that of the first winding means 70A. Therefore, the reference numeral "B" is added to the end of the notation for the configuration of the first winding means 70A, and a detailed explanation is omitted. The unwanted portion cutting means 77 includes a cutting blade 773 supported by a slider 772 of a linear motor 771, which is a drive device provided on the rear side of the arm 74. The winding means 78 includes first and second blowing means 781 and 782 that blow gas AI onto the tip of the unwanted portion AS1 using a pressurizing means such as a pressurizing pump or turbine (not shown).

[0027] First, we will explain the step (S1) of applying semiconductor processing adhesive tape to the surface of a semiconductor wafer having a front and back surface on which circuits are formed, with reference to Figure 2.

[0028] First, the adhesive tape AS wound around the support roller 21 is set as shown in Figure 2, and its leading end is wrapped around and secured to the winding mechanism 70 installed downstream of the separation mechanism 6. Next, a transport means (not shown) places the semiconductor wafer WF on the support surface 36 of the inner table 35. At this time, the semiconductor wafer WF is placed so that its back surface is in contact with the support surface 36 of the inner table 35. Then, the support means 3 drives the linear motor 33 to raise or lower the inner table 35, adjusting it so that the upper surface 37 of the outer table 31 and the upper surface of the semiconductor wafer WF are on the same plane. Next, the pressing means 4 drives the linear motor 43 at the position shown by the solid line in Figure 2, lowering the pressing roller 46 to press the adhesive tape AS and attach it to the outer table 31. Then, the pressing means 4 drives the linear motor 41, moving the pressing roller 46 to the left to attach the adhesive tape AS to the semiconductor wafer WF.

[0029] By following the above procedure, the step of applying semiconductor processing adhesive tape to the surface of a semiconductor wafer having a front and back surface on which circuits are formed is completed in step (S1).

[0030] In this manufacturing method, the adhesive tape AS used in step (S1) can be any general adhesive tape used as a backgrind sheet without any particular limitations. In Figure 2, the symbol BS indicates a support sheet, and the symbol AD ​​indicates an adhesive layer. The support sheet of the adhesive tape may be a substrate, or it may be a laminate in which a buffer layer and a substrate are laminated. That is, the adhesive tape AS may be an adhesive tape in which an adhesive layer is laminated on one side of a substrate, or it may be an adhesive tape having a laminated structure in which a buffer layer, a substrate, and an adhesive layer are laminated in this order. The adhesive tape may also have other layers. Examples of such other layers include a primer layer and a layer for embedding bumps formed on the circuit surface of the wafer. Furthermore, a release sheet may be laminated on the surface of the adhesive layer to protect the adhesive layer until use. In addition, a coating layer may be provided on the surface of the buffer layer. Here, the buffer layer provided in the adhesive tape has the function of easing the stress during back grinding of the semiconductor wafer, thereby preventing cracks and chips from occurring in the semiconductor wafer. Furthermore, when the adhesive tape is attached to the semiconductor wafer and cut along the outer circumference of the semiconductor wafer, the semiconductor wafer is placed on the chuck table via the adhesive tape and back grinded. The presence of the buffer layer in the adhesive tape makes it easier to properly hold the semiconductor wafer on the chuck table. Thus, when performing back grinding of a semiconductor wafer, the presence of a buffer layer in the adhesive tape offers significant advantages. However, because the buffer layer is softer than the base material, it also has drawbacks. Specifically, when the adhesive tape is cut, the resin in the buffer layer may twist or twist, resulting in the generation of cut dust. According to this manufacturing method, even an adhesive tape having a laminated structure in which a buffer layer, a base material, and an adhesive layer are laminated in that order exhibits good cutting performance when cut with a blade, thus suppressing the generation of cut dust. Therefore, the above advantages can be achieved while suppressing the above disadvantages of adhesive tapes having a buffer layer.

[0031] Furthermore, examples of semiconductor wafers used in step (S1) of this manufacturing method include silicon wafers, gallium arsenide wafers, silicon carbide wafers, lithium tantalate wafers, lithium niobate wafers, gallium nitride wafers, indium phosphate wafers, and glass wafers. The thickness of a semiconductor wafer before backside grinding is not particularly limited, but it is usually around 500 μm to 1000 μm. Furthermore, circuit formation on the surface of semiconductor wafers can be carried out by various methods, including conventionally used methods such as etching and lift-off methods.

[0032] In this manufacturing method, when DBG is used, the semiconductor wafer to which the semiconductor processing adhesive tape is attached in step (S1) is a semiconductor wafer with grooves formed on its surface (circuit formation surface). A semiconductor wafer with grooves formed on its surface can be manufactured by blade dicing, laser dicing, or the like using a conventionally known wafer dicing apparatus. These grooves serve as the starting point for splitting the semiconductor wafer when the semiconductor wafer is back-ground in step (S2), which will be described later.

[0033] Furthermore, when the DBG modification method is adopted in this manufacturing method, the semiconductor wafer to which the semiconductor processing adhesive tape is attached in step (S1) is a semiconductor wafer in which a modified region has been formed internally. However, this modified region may be formed after step (S1). Semiconductor wafers with modified regions formed inside are fabricated by irradiating the inside of the semiconductor wafer with a laser or plasma focused on that area. The laser or plasma irradiation may be performed from either the front or back side of the semiconductor wafer. The modified region is a brittle part of the semiconductor wafer, and it serves as the starting point for splitting the semiconductor wafer when the back surface of the semiconductor wafer is ground in the process (S2) described later.

[0034] Next, we will explain the step (S1) in which the semiconductor processing adhesive tape is cut with a blade along the outer shape of the semiconductor wafer and the non-adhered portion of the semiconductor processing adhesive tape that is not attached to the semiconductor wafer is removed, with reference to Figure 2.

[0035] First, the cutting means 5 drives the linear motor 51 to lower the blade 56 and penetrate the adhesive tape AS. After this, the cutting means 5 drives the rotary motor 53 to rotate the blade 56 around the axis of the output shaft 54, thereby cutting the adhesive tape AS along the outer shape of the semiconductor wafer WF. The cutting speed is usually 10 to 300 mm / s. The temperature of the blade 56 during cutting may be room temperature, or the blade may be heated before cutting. After cutting is complete, the cutting means 5 drives the linear motor 51 to raise the blade 56, and the pressing means 4 drives the linear motor 43 to raise the pressing roller 46.

[0036] Next, the pressing means 4 drives the linear motor 41, moving the pressing roller 46 to the right and returning the pressing roller 46 to the position shown by the solid line. At the same time, the removal means 6 drives the rotary motor 62 and the pressing means 4 drives the linear motor 41, rotating the drive roller 63 and moving the slider 61 to the right, thereby removing the unwanted part AS1 from the outer table 31.

[0037] Next, the semiconductor wafer WF with the adhesive tape AS attached is transported by a transport means (not shown). Then, with the removal means 6 stopped driving the rotary motor 62, the supply means 2, pressing means 4, and winding means 70 drive the rotary motor 23, linear motor 41, and first rotary motor 75A, moving the slider 61 to the left, and the first winding member 71A winds up the unnecessary sheet AS1 while pulling out the unused portion of the adhesive tape AS from the support roller 21. Then, a new semiconductor wafer WF is placed on the inner table 35, and the same operation described above is repeated thereafter.

[0038] In step (S1) of this manufacturing method, as previously described, when the back side of the semiconductor wafer WF is considered downwards and the front side of the semiconductor wafer WF is considered upwards in the direction perpendicular to the horizontal plane of the semiconductor wafer WF, the blade 56 is advanced such that the cutting edge AS1a of the non-adhesive portion AS1 curves upwards. One method for advancing the blade 56 so that the cut edge AS1a of the non-adhesive portion AS1 of the adhesive tape AS curves upward is to adjust the angles of the A axis, B axis, and C axis of the blade 56. The following provides a detailed explanation of how to adjust the angles of the A, B, and C axes of the blade.

[0039] <Explanation of each part of the blade> Before explaining how to adjust the angles of the A, B, and C axes of the blade, we will describe each part of the blade using Figure 3. Figure 3(a) is a side view of the blade, and Figure 3(b) is a cross-sectional view of Figure 3(a) along line P-P'. Figure 3(c) is a modified example of Figure 3(a). The blade 56 has a cutting edge 56a and a ridge 56. When cutting a material, the blade 56 is advanced in the order of cutting edge 56a, then ridge 56b to cut. In the following explanation, the longitudinal axis of the blade 56 (the axis in the Z-axis direction) will be referred to as the "major axis of the blade." The major axis of the blade is preferably parallel to the crest 56b of the blade. In the following explanation, the axis that connects the center line in the width direction of the crest 56b to the cutting edge 56a and is perpendicular to the major axis of the blade will be referred to as the "minor axis of the blade." Furthermore, blades generally have an inclined portion that is tilted in the direction of blade movement, as shown in Figure 3(c), and this inclined portion is often considered the cutting edge 56a. When using such a blade, the "angle of the A axis of the cutting edge of the blade" in the following explanation refers to the angle with respect to the inclined portion that serves as the cutting edge. In this embodiment, the X-axis, Y-axis, and Z-axis have the following meanings. The Y-axis is the tangential axis of the semiconductor wafer (WF), and the point of contact between the Y-axis and the semiconductor wafer (WF) is the origin. Furthermore, the direction of blade movement along the Y-axis is considered the positive direction. The X-axis is perpendicular to the Y-axis and extends from the origin to the center point of the semiconductor wafer WF. The Z-axis is an axis perpendicular to the XY plane.

[0040] <Adjusting the angle of the blade's A-axis> In this specification, the A-axis is an axis that rotates about the X-axis, as is the case with typical machine tools. The angle of the A-axis is, in detail, the tilt angle of the cutting edge 56a of the blade 56 with respect to the direction of travel of the blade 56, as shown in Figure 4. When the cutting edge 56a is parallel to the normal direction (Z-axis direction) to the horizontal plane of the semiconductor wafer WF (or adhesive tape AS), the angle of the A-axis of the cutting edge 56a of the blade 56 is 0°. When the blade 56 is tilted in the direction of travel and the cutting edge 56a is parallel to the horizontal plane of the semiconductor wafer WF (or adhesive tape AS), the angle of the A-axis of the cutting edge 56a of the blade 56 is +90°. °Furthermore, if the blade 56 is tilted in the opposite direction to the direction of travel and the cutting edge 56a is parallel to the horizontal plane of the semiconductor wafer WF (or adhesive tape AS), the angle of the A-axis of the cutting edge 56a of the blade 56 is -90. ° That is the case. With axis A as the axis of rotation, the range of motion of the cutting edge 56a of the blade 56 is typically greater than -90° and less than +90°.

[0041] In one aspect of the present invention, the blade is adjusted to satisfy the following condition (α1) when it is advanced. Condition (α1): Adjust the angle of the A-axis at the cutting edge of the blade to less than 0°. In other words, in one aspect of the present invention, when the blade is advanced, the cutting edge of the blade is tilted in the opposite direction to the direction of advancement. This allows the blade 56 to advance so that the cut edge AS1a of the non-adhesive portion AS1 of the adhesive tape AS curves upward, thereby suppressing the generation of cut dust during cutting. Furthermore, from the viewpoint of making it easier to suppress the generation of cut dust during cutting, the angle of the A-axis of the cutting edge of the blade is -5° or less, more preferably -10° or less, even more preferably -20° or less, and even more preferably -30° or less. Also, it is preferably -70° or more, more preferably -60° or more, even more preferably -50° or more, and even more preferably -40° or more.

[0042] The angle of the A-axis of the cutting edge 56a of the blade 56 can be adjusted as appropriate by various mechanisms such as the drive mechanism and swivel mechanism provided in the cutting means 5 described above. Furthermore, the angle of the A-axis of the cutting edge 56a of the blade 56 can also be adjusted by changing the shape of the cutting edge 56a of the blade 56. For example, as shown in Figure 5, by making the shape of the blade 56 roughly boot-shaped, and using the inclined portion formed toward the lower end of the blade 56 as the cutting edge 56a, and inclining the cutting edge 56a in the opposite direction to the direction of travel, the angle of the A-axis of the cutting edge 56a of the blade 56 can be adjusted to less than 0°. Alternatively, the angle of the A-axis of the cutting edge 56a of the blade 56 can be adjusted to less than 0° by inserting the blade 56 from the adhesive layer side of the adhesive tape AS.

[0043] <Adjustment of the B-axis and C-axis of the blade> In this specification, the B-axis is an axis that rotates about the Y-axis, similar to a typical machine tool. As shown in Figure 6, the angle of the B-axis is the tilt angle of the blade 56 with respect to the horizontal plane of the semiconductor wafer WF (or adhesive tape AS). When the direction normal to the horizontal plane of the semiconductor wafer WF (or adhesive tape AS) (Z-axis) and the long axis of the blade 56 are parallel, the angle of the B-axis is 0°. When the blade 56 tilts in a direction approaching the semiconductor wafer WF (or adhesive tape AS) and the long axis of the blade 56 becomes parallel to the horizontal plane of the semiconductor wafer WF (or adhesive tape AS), the angle of the B-axis is +90°. ° Furthermore, when the blade 56 is tilted away from the semiconductor wafer WF (or adhesive tape AS), and the long axis of the blade 56 becomes parallel to the horizontal plane of the semiconductor wafer WF (or adhesive tape AS), the angle of the B axis is -90. ° That is the case. With the B axis as the axis of rotation, the range of motion of the blade 56 is typically greater than -90° and less than +90°.

[0044] Furthermore, in this specification, the C-axis is an axis that rotates about the Z-axis, similar to a typical machine tool. As shown in Figure 8, the angle of the C axis is the rotation angle of the blade 56 with respect to the center line in the width direction of the ridge 56b of the blade 56. In the XY plane, when the minor axis of the blade 56 is parallel to the tangent to the outer circumference of the semiconductor wafer WF, the angle of the C axis is 0 ° When the blade 56 is rotated counterclockwise and its minor axis becomes perpendicular to the tangent to the outer circumference of the semiconductor wafer WF, the angle of the C axis is 90°. When the blade 56 is rotated clockwise and its minor axis becomes perpendicular to the tangent to the outer circumference of the semiconductor wafer WF, the angle of the C axis is -90°. A gap is appropriately provided between the side of the blade 56 and the semiconductor wafer WF according to the angle of the C axis, allowing the blade 56 to rotate while keeping the blade tip 56a close to the semiconductor wafer without the blade tip 56a and the semiconductor wafer WF coming into contact. In Figure 8, the paper plane is the XY plane, and the distance from the paper to the viewer is the Z axis. The range of motion of the blade 56, with the C axis as the axis of rotation, is typically greater than -90° and less than +90°.

[0045] In one aspect of the present invention, the blade is adjusted to satisfy the following condition (β1) when it is advanced. Condition (β1): The angle of the blade's B axis is adjusted to be greater than 0° and less than +45°, and the angle of the blade's C axis is greater than 0° and less than +30° ° Adjust to less than. This allows the blade 56 to advance so that the cut edge AS1a of the non-adhesive portion AS1 of the adhesive tape AS curves upward, thereby suppressing the generation of cut dust during cutting. Furthermore, from the viewpoint of making it easier to suppress the generation of cut dust during cutting, the angle of the B axis is preferably +5° or more, more preferably +10° or more, and even more preferably +15° or more. Also, it is preferably +40° or less, more preferably +35° or less, and even more preferably +30° or less. From a similar viewpoint, the angle of the C-axis is preferably +5° or more, more preferably +10° or more. It is also preferably +25° or less, more preferably +20° or less.

[0046] The angles of the B-axis and C-axis of the cutting edge 56a of the blade 56 can be adjusted as appropriate by various mechanisms such as the drive mechanism and pivot mechanism provided in the cutting means 5 described above. Furthermore, the angles of the B-axis and C-axis of the cutting edge 56a of the blade 56 can also be adjusted by changing the shape of the cutting edge 56a of the blade 56. For example, as shown in Figure 7, by making the shape of the blade 56 a V-shape and forming the cutting edge 56a on the inclined portion, and tilting the cutting edge 56a in a direction that approaches the semiconductor wafer WF (or adhesive tape AS), the angle of the B-axis of the cutting edge 56a of the blade 56 can be adjusted to be greater than 0° and less than +45°.

[0047] <Adjustment of the angles of the B axis and C axis when condition (α1) is met> When the above condition (α1) is met, the angles of the B axis and C axis are not particularly limited, but from the viewpoint of making it easier to suppress the generation of cut dust during cutting, it is preferable to further satisfy the following condition (α2). Condition (α2): Adjust the angle of the B axis of the cutting edge of the blade to 0° or greater, and also adjust the angle of the C axis of the cutting edge of the blade to 0° or greater. Furthermore, when the above condition (α1) is met, from the viewpoint of further suppressing the generation of cut dust during cutting, the angle of the B axis is preferably +40° or less, more preferably +30° or less, even more preferably +20° or less, even more preferably +10° or less, even more preferably +5° or less, and most preferably 0°. Furthermore, if the above condition (α1) is met, from a similar viewpoint, the angle of the C axis is preferably +25° or less, more preferably +20° or less, even more preferably +10° or less, even more preferably +5° or less, and most preferably 0°.

[0048] <Adjustment of the A-axis angle when condition (β1) is met> If the above condition (β1) is met, the angle of the A-axis is not particularly restricted. However, from the viewpoint of making it easier to suppress the generation of cut dust during cutting, the angle is preferably -70° or higher, more preferably -60° or higher, even more preferably -50° or higher, and even more preferably -40° or higher. Also, it is preferably +70° or lower, more preferably +60° or lower, even more preferably +50° or lower, and even more preferably +40° or lower.

[0049] <Coefficient of friction> In one embodiment of this manufacturing method, when cutting semiconductor processing adhesive tape along the outer shape of a semiconductor wafer with a blade, it is preferable that the coefficient of friction between the semiconductor processing adhesive tape and the blade be low, in order to further suppress the generation of cut dust by suppressing friction between the semiconductor processing adhesive tape and the blade. Specifically, it is preferable that the coefficient of friction be 0.25 or less. According to the inventors' studies, it has been confirmed that the cutting performance of the semiconductor processing adhesive tape by the blade can be further improved by setting the coefficient of friction between the semiconductor processing tape and the blade to 0.25 or less. The coefficient of friction can be adjusted by one or more treatments selected from surface polishing, surface coating, and material modification of the blade.

[0050] After process (S1) is completed, the semiconductor wafer with the adhesive tape for semiconductor processing is sent to the next process (S2).

[0051] [Process (S2)] In step (S2), the back surface of the semiconductor wafer is ground. In detail, after process (S1) is completed, the semiconductor wafer with the semiconductor processing adhesive tape attached is placed on the chuck table and held in place by suction to the chuck table. At this time, the semiconductor wafer with the semiconductor processing adhesive tape attached is placed on the chuck table so that the outermost surface (substrate or buffer layer) of the support sheet of the semiconductor processing adhesive tape is in direct contact with the chuck table. In other words, the semiconductor wafer is positioned with the surface side facing the chuck table.

[0052] The semiconductor wafer may be diced into individual pieces after step (S2) (Embodiment 1). Furthermore, the semiconductor wafer may be pulverized in step (S2) (Embodiment 2). Specifically, as the semiconductor wafer, a semiconductor wafer having grooves formed on its surface may be used, and in process (S2), the semiconductor wafer may be divided into multiple chips starting from the grooves. Furthermore, as the semiconductor wafer, a semiconductor wafer with a modified region formed inside may be used, or a modified region may be formed inside the semiconductor wafer after step (S1), and in step (S2), the semiconductor wafer may be divided into multiple chips starting from the modified region.

[0053] <Aspect 1> In embodiment 1, after performing step (S2), step (S3) is performed to separate the semiconductor wafer into individual pieces. In Embodiment 1, a semiconductor wafer without a division starting point is used, rather than a semiconductor wafer having a division starting point such as a semiconductor wafer with grooves formed on its surface or a semiconductor wafer with a modified region formed inside. (Process (S2)) In step (2), the back surface of the semiconductor wafer on the chuck table is ground. The thickness of the semiconductor wafer after backside grinding is not particularly limited, but is preferably about 5 μm to 100 μm, and more preferably 10 μm to 45 μm.

[0054] (Process (S3)) In step (S3), the semiconductor wafer that has undergone step (S2) is diced into individual pieces. Specifically, after step (S2), the semiconductor processing adhesive tape is peeled off the semiconductor wafer that has been back-ground. Next, a dicing tape is attached to the back side of the semiconductor wafer, and dicing is performed. Dicing can be carried out using conventionally known methods such as blade dicing or laser dicing, as appropriate.

[0055] The shape of the individual semiconductor chips may be rectangular or elongated, such as a rectangle. The thickness of the individual semiconductor chips is not particularly limited, but is preferably about 5 μm to 100 μm, and more preferably 10 μm to 45 μm. The area of ​​the individual semiconductor chips is not particularly limited, but is preferably 600 mm². 2 Less than, more preferably 400 mm 2 Less than 300 mm, more preferably 300 mm 2 It is less than.

[0056] <Aspect 2> In embodiment 2, in step (S2), the semiconductor wafer is back-ground and the semiconductor wafer is divided into individual pieces. (Process (S2)) In step (S2), the back surface of the semiconductor wafer on the chuck table is ground to separate the semiconductor wafer into multiple semiconductor chips.

[0057] In the first embodiment of Embodiment 2, a semiconductor wafer with grooves formed on its surface is used. In this case, the back surface of the semiconductor wafer is ground down to at least the bottom of the grooves. This back surface grinding causes the grooves to become notches that penetrate the semiconductor wafer, and the semiconductor wafer is divided by these notches into individual semiconductor chips.

[0058] Furthermore, in the second embodiment of Embodiment 2, a semiconductor wafer with a modified region formed inside is used. Alternatively, the modified region may be formed inside the semiconductor wafer after step (S1). In the second embodiment of Embodiment 2, backside grinding may be performed up to the modified region, but it is not necessary to reach the modified region precisely. That is, backside grinding may be performed up to a position close to the modified region so that the semiconductor wafer is broken down into individual semiconductor chips starting from the modified region.

[0059] Alternatively, the obtained semiconductor chips may be fitted with a pickup tape (described later), and then the pickup tape may be stretched to widen the gaps between the chips.

[0060] Additionally, after the backside grinding is complete and prior to picking up the chip, dry polishing may be performed.

[0061] The shape, thickness, and area of ​​the individual semiconductor chips are as described in Embodiment 1. Furthermore, when using a semiconductor wafer with a modified region formed internally, it becomes easy to set the thickness of the individual semiconductor chips to 50 μm or less, more preferably 10 μm to 45 μm.

[0062] The semiconductor processing adhesive tape of the present invention exhibits excellent cutability with a blade. Therefore, in the above process (S1), cut dust is less likely to be generated. Consequently, even when manufacturing thin and miniaturized semiconductor chips in the process (S2) of Embodiment 1 and the process (S2) of Embodiment 2, the occurrence of chipping or damage to the semiconductor chip caused by the cut dust is suppressed.

[0063] After step (S2), the semiconductor processing adhesive tape is peeled off the individual semiconductor wafers (i.e., multiple semiconductor chips). This process is carried out, for example, by the following method. If the adhesive layer of the adhesive tape for semiconductor processing is formed from an energy-ray curable adhesive, the adhesive layer is cured by irradiating it with energy rays. Next, a pickup tape is attached to the back side of the individual semiconductor wafers, and its position and orientation are aligned so that it can be picked up. At this time, a ring frame placed on the outer circumference of the wafer is also attached to the pickup tape, and the outer edge of the pickup tape is fixed to the ring frame. The wafer and ring frame may be attached to the pickup tape at the same time, or at different times. Next, the adhesive tape is peeled off from the multiple semiconductor chips held on the pickup tape.

[0064] Subsequently, multiple semiconductor chips on the pickup tape are picked up and fixed onto a substrate or the like to manufacture a semiconductor device. The pickup tape is not particularly limited, but for example, it is composed of an adhesive tape comprising a base material and an adhesive layer provided on at least one side of the base material.

[0065] Alternatively, adhesive tape can be used instead of pickup tape. Examples of adhesive tape include a laminate of a film-like adhesive and a release sheet, a laminate of dicing tape and a film-like adhesive, and a dicing-die bonding tape consisting of an adhesive layer and a release sheet that has the functions of both dicing tape and die bonding tape. In addition, a film-like adhesive may be bonded to the back side of the individual semiconductor wafers before applying the pickup tape. When using a film-like adhesive, the film-like adhesive may be the same shape as the wafer.

[0066] When using adhesive tape or when a film-like adhesive is applied to the back side of a semiconductor wafer that has been separated before applying the pickup tape, multiple semiconductor chips on the adhesive tape or pickup tape are picked up together with the adhesive layer, which is divided to match the shape of the semiconductor chips. The semiconductor chips are then fixed onto a substrate or the like via the adhesive layer, and a semiconductor device is manufactured. The division of the adhesive layer is performed by laser or expansion.

[0067] The semiconductor device manufacturing method of the present invention has been described above. The semiconductor processing adhesive tape of the present invention is particularly suitable for use in DBG deformation methods, which yield a group of semiconductor chips with a smaller calf width and thinner design when semiconductor wafers are separated into individual pieces. [Examples]

[0068] The present invention will be specifically described by the following examples, but the present invention is not limited to the following examples.

[0069] [Preparation of adhesive tape for semiconductor processing] A semiconductor processing adhesive tape was prepared having a laminated structure in which a buffer layer, a substrate, and an adhesive layer are stacked in that order.

[0070] <Formation of a buffer layer> A buffer layer composition was obtained by mixing 75 parts by mass of urethane acrylate oligomer (CN8888, manufactured by Arkema Corporation) and 25 parts by mass of 4-tert-butylcyclohexanol acrylate, totaling 100 parts by mass, with 2.0 parts by mass of a photopolymerization initiator (BASF's "Irgacure 1173," 2-hydroxy-2-methyl-1-phenylpropan-1-one). The obtained buffer layer composition was coated onto a substrate PET film (Toyobo Co., Ltd.'s "Cosmoshine A4300", a double-sided easy-adhesion PET film, thickness: 50 μm) using a knife-coating method to form a buffer layer composition layer with a thickness of 28 μm. Immediately after coating, the buffer layer composition layer was irradiated with a high-pressure mercury lamp at an illuminance of 160 mW / cm². 2 , irradiation amount 500mJ / cm 2 By irradiating with ultraviolet light under these conditions, the buffer layer composition layer was cured, forming a 28 μm thick buffer layer on one side of the PET film substrate, thereby producing a PET substrate with a buffer layer.

[0071] <Adhesive layer> An acrylic polymer was obtained by copolymerizing 65 parts by mass of n-butyl acrylate (BA), 15 parts by mass of methyl methacrylate (MMA), and 28 parts by mass of 2-hydroxyethyl acrylate (2HEA). 2-methacryloyloxyethyl isocyanate (MOI) was then reacted with the copolymer so as to add to 80 mol% of the total hydroxyl groups of the acrylic polymer, thereby obtaining an energy-ray curable acrylic resin (Mw: 500,000). To 100 parts by mass of this energy-ray curable acrylic resin, 6 parts by mass of a polyfunctional urethane acrylate, which is an energy-ray curable compound, 0.375 parts by mass of an isocyanate crosslinking agent ("Coronate L" manufactured by Tosoh Corporation), and 1 part by mass of bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide as a photopolymerization initiator were added, and the mixture was diluted with methyl ethyl ketone to prepare a coating solution of an adhesive composition with a solid content of 32% by mass.

[0072] <Manufacturing of adhesive tapes for semiconductor processing> A coating solution of the adhesive composition obtained above was applied to the release surface of a release sheet (Lintec Corporation, product name "SP-PET381031"), and then heated and dried to form an adhesive layer with a thickness of 30 μm on the release sheet. Then, an adhesive layer was bonded to the PET substrate with a buffer layer to create an adhesive tape for semiconductor processing having a laminated structure of buffer layer / PET substrate / adhesive layer.

[0073] [Measurement of various physical properties of the buffer layer and substrate] The elastic modulus, fracture energy, fracture stress, and fracture strain of the buffer layer were measured using a precision universal testing machine (device name "Autograph AG-IS" manufactured by Shimadzu Corporation). Specifically, a measurement sample of the buffer layer measuring 1.5 mm in width, 150 mm in length, and 0.2 mm in thickness was prepared. This measurement sample was then measured under the following conditions: 100 mm between chucks (25 mm on each end of the longitudinal direction of the measurement sample was fixed to the apparatus), tensile speed of 200 mm / sec, 23°C, and 50% RH.

[0074] <Evaluation of cutting performance by blade (1): Evaluation by simulation (A-axis)> Using the general-purpose finite element analysis software "Abaqus," we simulated and evaluated the cross-sectional state of semiconductor processing adhesive tape when it is cut with a blade. The analysis model is shown in Figure 9. Furthermore, regarding the blade, the use of an art knife (OLFA, model number "XB10") was assumed, and only the part of the art knife involved in cutting was modeled and its dimensions were entered. Figure 10 shows the actual dimensions of the blade used in the simulation. The analytical model assumed a rectangular semiconductor wafer and a semiconductor processing adhesive tape having a laminated structure in which a buffer layer and a substrate are stacked on the semiconductor wafer. In this analytical model, one end of the semiconductor processing adhesive tape is assumed to be constrained to the semiconductor wafer, and the other end is assumed to be completely constrained to the outer perimeter table. Then, with the angle of the B-axis and C-axis of the blade fixed at 0°, and the angle of the A-axis of the cutting edge of the blade adjusted as follows, the state of the cross-section of the adhesive tape for semiconductor processing was analyzed when the blade was moved in a linear direction along the semiconductor wafer at a cutting speed of 80 mm / s. In the above analysis model, the cutting edge properties were assumed to be rigid. Example I-1 sim.: A-axis = -32.8° Example I-2sim.: A-axis = -7.2° ·Comparative example I-1sim.:A axis=0° ·Comparative example 1-2sim.:A axis=+32.8° ·Comparative example I-3sim.:A axis=+62.8° The thickness of the buffer layer was set to 28 μm. The thickness of the substrate was set to 50 μm. Furthermore, the physical properties of the buffer layer and substrate were input as stress-strain data measured by the above-mentioned precision universal testing machine, along with the elastic modulus, yield stress, and fracture point based on that data. The coefficient of friction between the blade and the buffer layer was set to 0.25.

[0075] The evaluation criteria were as follows, with a score of 4 or higher considered a passing grade. 1: The sheet cross-section is very rough. 2: The sheet cross-section is rough. 3: The sheet cross-section is slightly rough. 4: There is only slight roughness visible on the sheet cross-section. 5: No roughness is observed in the sheet cross-section.

[0076] <Evaluation of cutting performance by blade (2): Evaluation by simulation (B axis and C axis)> The simulation was performed in the same manner as in the evaluation of cutting performance by the blade (1), except that the angle of the A-axis of the blade tip was fixed at 32.8°, -32.8°, or 62.8°, and the angles of the B-axis and C-axis of the blade were adjusted as follows, to evaluate the state of the cross-section when semiconductor processing adhesive tape was cut by the blade. Example II-1 sim.: A-axis = +32.8°, B-axis = +30°, C-axis = +20° Example II-2 sim.: A-axis = +32.8°, B-axis = +25°, C-axis = +20° Example II-3sim.: A-axis = +32.8°, B-axis = +15°, C-axis = +10° Example II-4sim.: A-axis = +32.8°, B-axis = +5°, C-axis = +5° Example II-5sim.: A-axis = -32.8°, B-axis = +5°, C-axis = +5° Comparative example II-1sim.: A axis = +32.8°, B axis = +15°, C axis = 0° Comparative example II-2sim.: A axis=+32.8°, B axis=0°, C axis=+10° Comparative example II-3sim.: A axis = +62.8°, B axis = +15°, C axis = 0° Comparative example II-4sim.: A axis=+32.8°, B axis=0°, C axis=0° Comparative example II-5sim.: A axis = +32.8°, B axis = +45°, C axis = +20°

[0077] <Evaluation of cutting performance by blade (3): Experimental evaluation (A-axis)> The prepared semiconductor processing adhesive tape was attached to a silicon wafer with a diameter of 12 inches and a thickness of 775 μm using a backgrind tape laminator (Lintec Corporation, model name "RAD-3510F / 12"). The semiconductor processing adhesive tape was then cut along the outer edge of the silicon wafer using an art knife (OLFA Corporation, model number "XB10"). The art knife was inserted from the buffer layer side of the semiconductor processing adhesive tape. The B-axis angle and C-axis angle of the art knife were fixed at 0°, and the A-axis angle of the blade tip was adjusted as follows, resulting in a cutting speed of 80 mm / s. The cross-section of the cut semiconductor processing adhesive tape was observed with a scanning electron microscope (SEM) and evaluated using the same criteria as for the evaluation of cutting performance by the blade (1). ·Comparative example 1-2exp.:A axis=+32.8° ·Comparative example I-3exp.: A axis=+62.8°

[0078] <Evaluation of cutting performance by blades (4): Experimental evaluation (axis B and axis C)> The experiment was conducted in the same manner as in the evaluation of cutting performance by the blade (3), except that the angle of the A axis of the art knife blade tip was fixed at +32.8° and the angles of the B axis and C axis of the art knife were adjusted as follows. The cross-section of the semiconductor processing adhesive tape that was cut was observed with a scanning electron microscope (SEM) and evaluated using the same criteria as in the evaluation of cutting performance by the blade (1). Example II-3 exp.: A-axis = +32.8°, B-axis = +15°, C-axis = +10° Example II-4 exp.: A-axis = +32.8°, B-axis = +5°, C-axis = +5° Comparative example II-1exp.: A axis = +32.8°, B axis = +15°, C axis = 0° Comparative example II-2exp.: A axis=+32.8°, B axis=0°, C axis=+10° Comparative example II-4exp.: A axis = +32.8°, B axis = 0°, C axis = 0° Comparative example II-6exp.: A axis = +32.8°, B axis = +15°, C axis = +30°

[0079] Table 1 shows the results for "Evaluation of cutting performance by blade (1): Evaluation by simulation (A-axis)" and "Evaluation of cutting performance by blade (3): Evaluation by experiment (A-axis)". Furthermore, Table 2 shows the results for "Evaluation of cutting performance by blade (2): Evaluation by simulation (B axis and C axis)" and "Evaluation of cutting performance by blade (4): Evaluation by experiment (B axis and C axis)". Furthermore, Figure 11 shows the analysis images of Example II-3sim. and Comparative Example II-2sim. in "Evaluation of Cutting Performance by Blade (2): Evaluation by Simulation (B-axis and C-axis)," and Figure 12 shows the scanning electron microscope (SEM) observation results of Example II-3exp. and Comparative Example II-2exp. in "Evaluation of Cutting Performance by Blade (4): Evaluation by Experiment." Note that the units of the numerical values ​​listed in the A-axis, B-axis, and C-axis columns in Tables 1 and 2 are degrees (°).

[0080] [Table 1]

[0081] [Table 2]

[0082] From Table 1, the following can be seen. In Examples I-1sim. and I-2sim., where the angle of the A-axis at the cutting edge of the blade is less than 0° and condition (α1) is met, the blade can be advanced so that the cut edge of the non-adhesive portion of the adhesive tape curves upward, and in both cases, the cutting performance by the blade is good. Therefore, it can be seen that the generation of cut dust during cutting is suppressed. In contrast, in Comparative Examples I-1sim. to I-3sim., where the angle of the A-axis at the cutting edge of the blade is 0° or greater and condition (α1) is not met, the blade cannot be advanced in such a way that the cut edge of the non-adhesive portion of the adhesive tape curves upward, and in all cases, the cutting performance by the blade is inferior. Therefore, it can be seen that the generation of cut dust during cutting cannot be suppressed.

[0083] Furthermore, Comparative Examples I-2exp. and I-3exp. are the results of experimental verification of Comparative Examples I-2sim. and I-3sim. It can be seen that the evaluation results of the cutting performance by the blade examined in Comparative Examples I-2exp. and I-3exp. are in complete agreement with the evaluation results of the cutting performance by the blade examined in Comparative Examples I-2sim. and I-3sim.

[0084] From Table 2, the following can be seen. The angle of the blade's B axis is greater than 0° and less than +45°, and the angle of the blade's C axis is greater than 0° and less than +30° °In Examples II-1sim. and II-5sim., where the value is less than 0° and condition (β1) is met, the blade can be advanced so that the cut edge of the non-adhesive portion of the adhesive tape curves upward, and in both cases, the cutting performance by the blade is good. Furthermore, from the results shown in Examples II-1sim. and II-4sim., it can be seen that even if the angle of the A axis is 0° or more and condition (α1) is not met, the cutting performance by the blade is good if condition (β1) is met. Therefore, it can be seen that the generation of cut dust during cutting is suppressed. In contrast, as in Comparative Example II-1sim. and Comparative Example II-3sim., when the angle of the blade's C-axis is 0° and condition (β1) is not met, and furthermore condition (α1) is also not met, the blade cannot be advanced in such a way that the cut edge of the non-adhesive portion of the adhesive tape curves upward, and in all cases, the cutting performance by the blade is inferior. As shown in Comparative Example II-2sim., even when the angle of the B axis of the blade is 0° and condition (β1) is not met, and furthermore condition (α1) is also not met, the blade cannot be advanced in such a way that the cut edge of the non-adhesive portion of the adhesive tape curves upward, indicating that the cutting performance by the blade is inferior. Furthermore, as in Comparative Example II-4sim., when both the angle of the B-axis and the C-axis of the blade are 0°, and condition (β1) is not met, and condition (α1) is also not met, the blade cannot be advanced in such a way that the cut edge of the non-adhesive portion of the adhesive tape curves upward, indicating that the cutting performance by the blade is inferior. Furthermore, as in Comparative Example II-5sim., when the angle of the B-axis of the blade is 45°, and condition (β1) is not met, and condition (α1) is also not met, the blade cannot be advanced in such a way that the cut edge of the non-adhesive portion of the adhesive tape curves upward, resulting in poor cutting performance by the blade. Therefore, it can be seen that the generation of cut dust during cutting cannot be suppressed in the cases of Comparative Examples II-1sim. to II-5sim.

[0085] Furthermore, Examples II-3exp., II-4exp., Comparative Example II-1exp., Comparative Example II-2exp., and Comparative Example II-4exp. are the results of experimentally verifying Examples II-3sim., Examples II-4sim., Comparative Example II-1sim., Comparative Example II-2sim., and Comparative Example II-4sim. It can be seen that the evaluation results of cutting performance by the blade examined in Examples II-3exp., Examples II-4exp., Comparative Example II-1exp., Comparative Example II-2exp., and Comparative Example II-4exp. are in complete agreement with the evaluation results of cutting performance by the blade examined in Examples II-3sim., Examples II-4sim., Comparative Example II-1sim., Comparative Example II-2sim., and Comparative Example II-4sim. This is also evident from the results shown in Figures 11 and 12. Furthermore, as in Comparative Example II-6exp., when the angle of the blade's C-axis is 30°, failing to satisfy condition (β1) and also failing to satisfy condition (α1), it is not possible to advance the blade so that the cut edge of the non-adhesive portion of the adhesive tape curves upward, resulting in poor cutting performance by the blade. [Explanation of Symbols]

[0086] AS adhesive tape for semiconductor processing AS1 Non-adhered portion of semiconductor wafer adhesive tape for semiconductor processing AS1a Cut edge of the non-adhesive portion of adhesive tape for semiconductor processing WF Semiconductor wafer 56 blades 56a Cutting edge 56b peak

Claims

1. The following steps (S1) and (S2) are included in this order: Step (S1): After applying semiconductor processing adhesive tape to the surface of a semiconductor wafer having a surface and a back surface on which circuits are formed, the semiconductor processing adhesive tape is cut with a blade along the outer shape of the semiconductor wafer, and the non-adhesive portion of the semiconductor processing adhesive tape that is not attached to the semiconductor wafer is removed. - Process (S2): A process of grinding the back surface of the semiconductor wafer. A method for manufacturing a semiconductor device, wherein in step (S1), when the back side of the semiconductor wafer is considered to be downward and the front side of the semiconductor wafer is considered upward in the direction perpendicular to the horizontal plane of the semiconductor wafer, the blade is advanced such that the cutting edge of the non-adhesive portion curves upward, A method for manufacturing a semiconductor device, wherein the following condition (α1) is satisfied when advancing the blade in the above step (S1). Condition (α1): Adjust the angle of the A-axis of the cutting edge of the blade to -5° or less.

2. Furthermore, a method for manufacturing a semiconductor device according to claim 1, which satisfies the following condition (α2). Condition (α2): The angle of the B axis of the blade is adjusted to 0° or more, and the angle of the C axis of the blade is adjusted to 0° or more.

3. The following steps (S1) and (S2) are included in this order: Step (S1): After applying semiconductor processing adhesive tape to the surface of a semiconductor wafer having a surface and a back surface on which circuits are formed, the semiconductor processing adhesive tape is cut with a blade along the outer shape of the semiconductor wafer, and the non-adhesive portion of the semiconductor processing adhesive tape that is not attached to the semiconductor wafer is removed. - Process (S2): A process of grinding the back surface of the semiconductor wafer. A method for manufacturing a semiconductor device, wherein in step (S1), when the back side of the semiconductor wafer is considered to be downward and the front side of the semiconductor wafer is considered upward in the direction perpendicular to the horizontal plane of the semiconductor wafer, the blade is advanced such that the cutting edge of the non-adhesive portion curves upward, A method for manufacturing a semiconductor device, wherein the following condition (β1) is satisfied when advancing the blade in the above step (S1). Condition (β1): The angle of the B axis of the blade is adjusted to be greater than 0° and less than or equal to +35°, and the angle of the C axis of the blade is adjusted to be greater than 0° and less than or equal to +25°.

4. In the method for manufacturing a semiconductor device according to any one of claims 1 to 3, Furthermore, a method for manufacturing a semiconductor device, including the following step (S3). • Process (S3): Process of dicing the semiconductor wafer to form individual pieces.

5. In the method for manufacturing a semiconductor device according to any one of claims 1 to 3, As the semiconductor wafer, a semiconductor wafer having grooves formed on its surface is used. A manufacturing method comprising the above step (S2), wherein the semiconductor wafer is divided into a plurality of chips starting from the grooves.

6. In the method for manufacturing a semiconductor device according to any one of claims 1 to 3, As the semiconductor wafer, a semiconductor wafer in which a modified region is formed internally is used, or a modified region is formed internally of the semiconductor wafer after the above step (S1). A manufacturing method comprising the above step (S2), wherein the semiconductor wafer is divided into a plurality of chips starting from the modified region.

Images