JP4488037B2 - Semiconductor wafer processing method - Google Patents

Description

  The present invention relates to a semiconductor wafer processing method for performing a series of processes including a process of dividing a semiconductor wafer on which a plurality of semiconductor elements are formed into individual semiconductor elements.

  A semiconductor device mounted on a substrate of an electronic device has a packaging process in which a lead frame pin or a metal bump is connected to a semiconductor element on which a circuit pattern is formed in a wafer state and sealed with a resin or the like. It is manufactured after. Along with the recent miniaturization of electronic devices, the miniaturization of semiconductor devices is also progressing, and in particular, efforts to make semiconductor elements thinner are being actively carried out.

  Thinned semiconductor elements have low strength against external forces, and in particular, in the dicing process of separating wafer-state semiconductor elements for each element, there is a problem that the processing yield is inevitably damaged during cutting and a reduction in processing yield is inevitable. . As a method of cutting such a thinned semiconductor element, a method of cutting a semiconductor wafer (plasma dicing) by forming a cutting groove by plasma etching instead of a mechanical cutting method has been proposed. (For example, refer to Patent Document 1).

In this plasma dicing, a dicing mask having a pattern corresponding to the boundary line arrangement of the semiconductor elements is formed on the semiconductor wafer so as to expose only the boundary portion to be cut in the semiconductor wafer to the plasma.
JP 2002-93752 A

  The above-mentioned dicing mask is generally formed by an optical method using photolithography. However, in the case of forming a dicing mask by photolithography, a complicated processing step with a high process cost is added, so that there is a problem that the total cost of the dicing step increases.

  Therefore, an object of the present invention is to provide a semiconductor wafer processing method capable of realizing plasma dicing at low cost.

  The semiconductor wafer processing method according to claim 1 is a semiconductor wafer processing method for dividing a semiconductor wafer on which a plurality of semiconductor elements are formed into semiconductor elements, on a circuit forming surface of the semiconductor wafer. A support member attaching step for attaching the support member, an adhesive layer forming step for forming an adhesive layer on the back surface of the circuit forming surface, a mask layer forming step for forming a mask layer on the adhesive layer, A mask layer and an adhesive layer in a boundary line region that separates adjacent semiconductor elements by irradiating the mask layer with laser light while relatively moving laser light with respect to the semiconductor wafer on which the mask layer is formed. Plasma processing of a semiconductor wafer in a state where a laser processing step to be removed, a mask layer and an adhesive layer in the boundary line region are removed, and a support member is attached to the circuit formation surface The boundary region of the semiconductor wafer is removed by plasma etching by Rukoto and a plasma dicing step of dividing each semiconductor element.

The semiconductor wafer processing method according to claim 2 is the semiconductor wafer processing method according to claim 1, wherein the semiconductor wafer is thinned by processing the back surface prior to the adhesive layer forming step. Execute the process.

  The semiconductor wafer processing method according to claim 3 is the semiconductor wafer processing method according to claim 1, wherein a mask layer removing step of removing the mask layer from the adhesive layer after the plasma dicing, and the plasma dicing are performed. And a pressure sensitive adhesive sheet attaching step of removing the support member from the circuit forming surface and attaching the pressure sensitive adhesive sheet to the adhesive layer.

  According to a fourth aspect of the present invention, there is provided a semiconductor wafer processing method according to the first aspect, wherein the semiconductor element is peeled from the pressure sensitive adhesive sheet together with an adhesive layer and transferred to the substrate after the pressure sensitive adhesive sheet pasting step. Includes die bonding process for mounting.

  A semiconductor wafer processing method according to a fifth aspect of the present invention is the semiconductor wafer processing method according to the first aspect, wherein the support member is an insulating sheet.

  A semiconductor wafer processing method according to a sixth aspect of the present invention is the semiconductor wafer processing method according to the first aspect, wherein the support member is the same size as the semiconductor wafer.

  A semiconductor wafer processing method according to a seventh aspect of the present invention is the semiconductor wafer processing method according to the third aspect, wherein the pressure-sensitive adhesive sheet is larger in size than the semiconductor wafer and is fixed around by a jig. Yes.

  The semiconductor wafer processing method of the present invention according to claim 8 is the semiconductor wafer processing method according to claim 1, wherein a sheet with an adhesive layer in which the adhesive layer and the mask layer are laminated together is attached to the back surface. Thus, the adhesive layer forming step and the mask layer forming step are simultaneously performed.

  According to the present invention, prior to plasma dicing in which a semiconductor wafer is removed by plasma etching and divided into semiconductor elements, the semiconductor wafer on which the mask layer is formed is irradiated with laser light to separate adjacent semiconductor elements. By performing laser processing to remove the mask layer and adhesive layer in the boundary line region, a dicing mask can be formed without performing a complicated processing process with high process cost, and plasma dicing can be realized at low cost. be able to.

(Reference Example 1)
1 and FIG. 2 are process explanatory views of a semiconductor wafer processing method according to Reference Example 1 of the present invention. FIG. 3 is a perspective view of a laser processing apparatus used in the semiconductor wafer processing method according to Reference Example 1 of the present invention. 4 is a sectional view of a plasma processing apparatus used in the semiconductor wafer processing method of Reference Example 1 of the present invention, and FIG. 5 is a perspective view of a die bonding apparatus used in the semiconductor wafer processing method of Reference Example 1 of the present invention. FIG. 6 is a process explanatory diagram of a die bonding process in the semiconductor wafer processing method of Reference Example 1 of the present invention.

  First, a semiconductor wafer processing method will be described with reference to FIGS. Here, a method of performing a series of processes including a process of dividing a semiconductor wafer formed with a plurality of semiconductor elements into individual semiconductor elements is shown.

In FIG. 1A, a plurality of semiconductor elements are formed on a semiconductor wafer 1, and a circuit forming portion 2 is provided for each semiconductor element on a circuit forming surface 1 a of the semiconductor wafer 1. On the upper surface of the circuit forming portion 2, an external connection electrode 3 is formed. When the processing is started, first, as shown in FIG. 1B, a sheet-like support member 4 is attached to the surface opposite to the circuit forming surface 1a, that is, the back surface 1b (support member attaching step). .

  The support member 4 is an insulating sheet made of an insulating material such as resin, and the same size as that of the semiconductor wafer 1 is used so that the support member 4 does not protrude to the outer peripheral side of the semiconductor wafer 1 in a state of being attached to the semiconductor wafer 1. Thereby, in the plasma dicing process described later, it is possible to prevent the support member 4 protruding from the semiconductor wafer 1 from being damaged by the plasma.

  Thereafter, as shown in FIG. 1C, a mask layer 5 is formed on the circuit forming surface 1a (mask layer forming step). The mask layer 5 is for forming a mask pattern used in a plasma dicing process, which will be described later, and is made of a material resistant to plasma using a fluorine-based gas, for example, aluminum or resin.

  In the case of using aluminum, a method of forming an aluminum thin film on the circuit formation surface 1a by vapor deposition, a method of attaching a foil-like aluminum film, or the like is used. When using a resin, a method of attaching a resin formed in a film shape, a method of applying a liquid resin on the circuit formation surface 1a by a method such as spin coating, or the like can be used.

  Next, as shown in FIG. 2A, the mask layer 5 is irradiated with laser light 6a from the laser irradiation unit 6 to remove the mask layer 5 in the boundary region 5a that separates adjacent semiconductor elements (laser). Processing step). This laser processing is performed while moving the laser beam 6a relative to the semiconductor wafer 1 on which the mask layer 5 is formed.

  The laser processing apparatus will be described with reference to FIG. In FIG. 3, the semiconductor wafer 1 on which the mask layer 5 is formed is held on the wafer holder 10. Above the wafer holding unit 10, a moving plate 17 on which the laser irradiation unit 6 and the camera 18 are mounted is disposed so as to be movable by the moving mechanism 16. The laser irradiation unit 6 irradiates the lower semiconductor wafer 1 with the laser beam generated by the laser generation unit 13.

  The camera 18 is an infrared camera, and images the semiconductor wafer 1 positioned below with infrared light. At this time, it is possible to take an image of a circuit pattern, a recognition mark, and the like on the circuit formation surface of the semiconductor wafer 1 through the mask layer 5. Then, the recognition result is processed by the recognition unit 15 so that the position of the semiconductor wafer 1 and the arrangement of the circuit patterns can be detected.

  The laser generator 13, the recognition unit 15, and the moving mechanism 16 are controlled by the control unit 14, and when the control unit 14 controls these units based on operation commands from the operation / input unit 11, the work data storage unit 12 The stored data is referenced. The work data storage unit 12 stores data related to the position of the dicing line, that is, the boundary line that separates adjacent semiconductor elements, and data related to the dicing width, that is, the removal width of the boundary line region 5a shown in FIG. Has been. Data writing to the work data storage unit 12 can be performed by the operation / input unit 11.

When performing laser processing on the semiconductor wafer 1 with this laser processing apparatus, the control unit 14 stores the actual position of the semiconductor wafer 1 detected by the recognition unit 15 and the work data storage unit 12. The moving mechanism 16 is controlled based on the data indicating the position of the dicing line. Accordingly, the moving mechanism 16 moves the laser irradiation unit 6 along the dicing line on the upper surface of the semiconductor wafer 1. Then, the control unit 14 controls the laser generation unit 13 based on the data related to the dicing width, so that the laser beam having an output suitable for removing the mask layer 5 with the removal width corresponding to the dicing width is obtained from the laser irradiation unit 6. Irradiated. As a result of this laser processing, a mask pattern is formed in which only the boundary region 5a that separates the semiconductor elements from each other in the mask layer 5 on the surface of the semiconductor wafer 1 is removed.

  The semiconductor wafer 1 in a state where the mask layer in the boundary region is removed and the mask pattern is formed and the support member 4 is attached to the back surface 1b is formed in the plasma dicing process as shown in FIG. Sent to. Here, the semiconductor wafer 1 in the above-described state is subjected to plasma treatment, so that the boundary line region 1d of the semiconductor wafer 1, that is, the portion corresponding to the boundary line region 5a in the mask layer 5 is removed by plasma etching. 1 is divided for each semiconductor element 1c.

  A plasma processing apparatus for performing this plasma dicing process will be described with reference to FIG. In FIG. 4, the inside of the vacuum chamber 20 is a sealed processing space for performing plasma processing on the semiconductor wafer 1. A high frequency side electrode 21 and a gas supply electrode 23 are disposed inside the vacuum chamber 20 so as to face each other. On the high frequency side electrode 21, the semiconductor wafer 1 to be processed is placed in a state surrounded by an insulating ring 22, and held by vacuum suction or electrostatic suction.

  A fluorine-based plasma generation gas is supplied to the gas supply hole 23 a provided in the gas supply electrode 23 by the plasma generation gas supply unit 26 through the control valve 25. The supplied plasma generating gas is sprayed uniformly on the semiconductor wafer 1 on the high frequency side electrode 21 through the porous plate 24 mounted on the lower surface of the gas supply electrode 23.

  In this state, by driving the high-frequency power supply unit 27 and applying a high-frequency voltage to the high-frequency side electrode 21, a fluorine-based gas plasma is generated between the gas supply electrode 23 and the high-frequency side electrode 21. As described above, plasma dicing is performed in which only the boundary line region 1d of the semiconductor wafer 1 made of silicon is removed by plasma etching. In the plasma dicing process, the cooling unit 28 is driven to circulate the refrigerant in the high-frequency electrode 21 to prevent the semiconductor wafer 1 from being heated by the heat of the plasma.

  Next, as shown in FIG. 2C, after the plasma dicing, the support member 4 is removed from the back surface 1b of each semiconductor element 1c, and the adhesive sheet 7 is attached to the back surface 1b (adhesive sheet attaching step). Specifically, the support member 4 is peeled off in a state where the circuit forming surface 1a of the semiconductor element 1c is attached to a temporary attachment sheet, and then an adhesive sheet is attached. Here, the pressure-sensitive adhesive sheet 7 has a size larger than that of the above-described semiconductor wafer 1 and the periphery thereof is fixed by a wafer ring 31 (jig) shown in FIG. 5, and the wafer ring 31 is gripped in the subsequent steps. Then handling is performed.

  After that, the divided mask layer 5b attached to the circuit formation surface of each semiconductor element 1c is peeled off from the circuit formation surface 1a and removed (mask layer removal step). As a result, as shown in FIG. 2D, each semiconductor element 1c is held on the adhesive sheet 7 in a lattice arrangement with the circuit formation surface facing upward, and in the die bonding step described below, the semiconductor element 1c is held. 1c is supplied in this state.

  Next, the die bonding process will be described. As shown in FIG. 5, the wafer ring holding table 30 holds a wafer ring 31 to which the adhesive sheet 7 is fixed. The semiconductor element 1c affixed to the adhesive sheet 7 is peeled off by the suction nozzle 33 of the bonding head 32, transferred and mounted on the substrate 35 held by the substrate holder 34, and bonded by an adhesive.

  This bonding operation will be described with reference to FIG. As shown in FIG. 6A, an adhesive 36 is applied in advance to the bonding position of the substrate 35 held by the substrate holder 34. The suction nozzle 33 that peels off the semiconductor element 1c from the adhesive sheet 7 transfers the semiconductor element 1c onto the substrate 35 and aligns it with the bonding position. Thereafter, as shown in FIG. 6B, the suction nozzle 33 is lowered to land the semiconductor element 1c on the substrate 35 through the adhesive 36, and is pressed with a predetermined bonding load.

  At this time, the substrate 35 may be heated by heating means built in the substrate holder 34 as necessary. Then, after the predetermined bonding time has elapsed, the suction nozzle 33 is raised so that the semiconductor element 1c with the circuit forming surface facing upward is applied to the substrate 35 by the solidified adhesive 36 as shown in FIG. It is fixed.

  In the semiconductor wafer processing method described above, the support member attaching step may be performed after the laser processing step is executed subsequent to the mask layer forming step. Further, the order of the adhesive sheet attaching step and the mask removing step may be changed, and the adhesive sheet 7 may be attached after removing the mask. In particular, when removing the mask by plasma treatment (plasma ashing), the plasma treatment is performed with the support member 4 attached, and then the support member 4 is peeled off and the adhesive sheet 7 is attached.

(Reference Example 2)
7 and 8 are process explanatory views of a semiconductor wafer processing method according to Reference Example 2 of the present invention. Reference Example 2 shows a method for performing a series of processes including a process of dividing a semiconductor wafer on which a plurality of semiconductor elements are formed into individual semiconductor elements, as in Reference Example 1.

  In FIG. 7A, a plurality of semiconductor elements are formed on the semiconductor wafer 1, and a circuit forming portion 2 is provided for each semiconductor element on the circuit forming surface 1 a of the semiconductor wafer 1. On the upper surface of the circuit forming portion 2, an external connection electrode 3 is formed. When the process is started, first, as shown in FIG. 7B, a sheet-like support member 44 similar to the support member 4 in Reference Example 1 is attached to the circuit forming surface 1a (support member attaching step). .

  Thereafter, the semiconductor wafer 1 with the support member 44 attached thereto is sent to a mechanical polishing apparatus, and as shown in FIG. 7C, the back surface 1b side is polished to reduce the thickness d of the semiconductor wafer 1. (For example, about 100 μm) (thinning step). Then, as shown in FIG. 7D, a mask layer 45 similar to the mask layer 5 in Reference Example 1 is formed on the back surface 1b of the thinned semiconductor wafer 1 (mask layer formation). Process). That is, in Reference Example 2, prior to the mask layer forming step, a thinning step is performed in which the back surface 1b is processed to thin the semiconductor wafer 1. In the thinning step, the damage layer formed on the surface layer of the back surface 1b by the polishing process may be removed by a plasma process or a wet etching process after the polishing process.

  Next, as shown in FIG. 8A, the mask layer 45 is irradiated with the laser beam 6a by the laser irradiation device 6 to remove the mask layer 45 in the boundary region 45a that separates adjacent semiconductor elements (laser). Processing step). This laser processing is performed using the laser processing apparatus shown in FIG.

The semiconductor wafer 1 in a state where the mask layer in the boundary line region is removed in this way to form a mask pattern and the support member 44 is attached to the back surface 1b is formed in a plasma dicing process as shown in FIG. Sent to. Here, as in Reference Example 1, plasma treatment is performed on the thinned semiconductor wafer 1 to remove the boundary line region 1d of the semiconductor wafer 1, that is, the portion corresponding to the boundary line region 45a in the mask layer 45 by plasma etching. Thus, the semiconductor wafer 1 is divided into individual semiconductor elements 1c.

  Next, as shown in FIG. 8C, the divided mask layer 45b attached to the back surface 1b of each semiconductor element 1c after plasma dicing is peeled off and removed (mask layer removing step). And after removing the support member 44 from the circuit formation surface 1a, the adhesive sheet 7 is affixed on the back surface 1b (adhesive sheet sticking process). As a result, as shown in FIG. 8 (d), each semiconductor element 1c is held on the adhesive sheet 7 in a lattice arrangement with the circuit formation surface facing upward, and the die shown in FIG. The substrate is bonded to the substrate 35 in the same process as the die bonding operation shown in FIG.

(Embodiment)
9 and 10 are process explanatory views of the semiconductor wafer processing method according to the embodiment of the present invention, and FIG. 11 is a process explanatory view of the die bonding step in the semiconductor wafer processing method of the embodiment of the present invention. The present embodiment shows a method of performing a series of processes including a process of dividing a semiconductor wafer on which a plurality of semiconductor elements are formed into individual semiconductor elements, as in Reference Example 2.

  9A, 9 </ b> B, and 9 </ b> C are the same as those shown in FIGS. 7A, 7 </ b> B, and 7 </ b> C in Reference Example 2. FIGS. Then, as shown in FIG. 9D, an adhesive layer 48 for die bonding is formed on the back surface 1b of the thinned semiconductor wafer 1 (adhesive layer forming step). Next, a mask layer 55 similar to the mask layer 5 shown in Reference Example 1 is formed over the adhesive layer 48 (mask layer forming step). That is, also in the embodiment, prior to the mask layer forming step, a thinning step for processing the back surface 1b to thin the semiconductor wafer 1 is performed. Note that the adhesive layer forming step and the mask layer forming step are performed by attaching a sheet with an adhesive layer in which the adhesive layer and the mask layer are laminated together in advance, without separately performing the adhesive layer formation and the mask layer formation. May be performed simultaneously.

  Next, as shown in FIG. 10A, the mask layer 55 and the adhesive layer 48 are irradiated with a laser beam 6a by the laser irradiation device 6, and the mask layer 55 in the boundary line region 55a that separates adjacent semiconductor elements from each other. Then, the adhesive layer 48 is removed (laser processing step). This laser processing is performed using the laser processing apparatus shown in FIG.

  The semiconductor wafer 1 in a state where the mask layer 55 and the adhesive layer 48 in the boundary line region 55a are removed in this way to form a mask pattern and the support member 54 is attached to the circuit forming surface 1a is shown in FIG. It is sent to the plasma dicing process as shown in (b). Here, as in Reference Example 2, the thinned semiconductor wafer 1 is subjected to plasma processing, so that the boundary region 1d of the semiconductor wafer 1, that is, the portion corresponding to the boundary region 55a in the mask layer 55 is obtained by plasma etching. As a result, the semiconductor wafer 101 is divided into individual semiconductor elements 1c.

  Next, as shown in FIG. 10C, after the plasma dicing, the divided mask layer 55b that has been stuck on the adhesive layer 48 formed on the back surface 1b of each semiconductor element 1c is peeled off and removed. (Mask layer removal step). And the adhesive sheet 7 is affixed on the back surface 1b which removed the support member 54 from the circuit formation surface 1a (adhesive sheet sticking process). As a result, as shown in FIG. 10D, each semiconductor element 1c is held on the adhesive sheet 7 in a lattice arrangement with the circuit formation surface facing upward, and in the die bonding process described below, the semiconductor element 1c is held. 1c is supplied in this state.

Next, the bonding operation will be described with reference to FIG. As shown in FIG. 11A, the suction nozzle 33 that peels the semiconductor element 1c together with the adhesive layer 48 from the pressure-sensitive adhesive sheet 7 transfers the semiconductor element 1c onto the substrate 35 and aligns it with the bonding position. Thereafter, as shown in FIG. 11B, the suction nozzle 33 is lowered to land the semiconductor element 1c on the substrate 35, and is pressed with a predetermined bonding load.

  At this time, by heating the substrate 35 by the heating means built in the substrate holder 34, the adhesive layer 48 is heated to form a fillet of the liquid adhesive 48a. Then, after a predetermined bonding time has elapsed, by raising the suction nozzle 33, as shown in FIG. 11C, the semiconductor element 1c with the circuit forming surface facing upward is bonded to an adhesive portion 48b in which the adhesive 48a is solidified. To be fixed to the substrate 35. In addition, you may make it heat the board | substrate 35 in a post process.

  As described above, in the semiconductor wafer processing method shown in this embodiment, the semiconductor wafer on which the mask layer is formed is removed prior to plasma dicing in which the semiconductor wafer is removed by plasma etching and divided into semiconductor elements. Then, laser processing is performed so as to remove the mask layer in the boundary region that divides adjacent semiconductor elements by irradiating laser light. As a result, it is possible to form a dicing mask without performing complicated processing steps with high process costs, and plasma dicing can be realized at low cost.

  The semiconductor wafer processing method of the present invention has an effect that a dicing mask can be formed without performing a complicated processing step with a high process cost, and plasma dicing can be realized at a low cost. This is useful for a series of processes including a process of dividing a semiconductor wafer on which semiconductor elements are formed into individual pieces of semiconductor elements.

Process explanatory drawing of the processing method of the semiconductor wafer of the reference example 1 of this invention Process explanatory drawing of the processing method of the semiconductor wafer of the reference example 1 of this invention The perspective view of the laser processing apparatus used in the processing method of the semiconductor wafer of the reference example 1 of this invention Sectional drawing of the plasma processing apparatus used in the processing method of the semiconductor wafer of the reference example 1 of this invention The perspective view of the die bonding apparatus used in the processing method of the semiconductor wafer of the reference example 1 of this invention Process explanatory drawing of the die bonding process in the processing method of the semiconductor wafer of the reference example 1 of this invention Process explanatory drawing of the processing method of the semiconductor wafer of the reference example 2 of this invention Process explanatory drawing of the processing method of the semiconductor wafer of the reference example 2 of this invention Process explanatory drawing of the processing method of the semiconductor wafer of embodiment of this invention Process explanatory drawing of the processing method of the semiconductor wafer of embodiment of this invention Process explanatory drawing of the die-bonding process in the processing method of the semiconductor wafer of embodiment of this invention

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Semiconductor wafer 1a Circuit formation surface 1b Back surface 1c Semiconductor element 4, 44, 54 Support member 5, 45, 55 Mask layer 6 Laser irradiation part 6a Laser beam 7 Adhesive sheet 48 Adhesive layer

Claims (8)

A semiconductor wafer processing method for dividing a semiconductor wafer on which a plurality of semiconductor elements are formed into semiconductor elements,
A support member attaching step for attaching a sheet-like support member to the circuit forming surface of the semiconductor wafer, an adhesive layer forming step for forming an adhesive layer on the back surface of the circuit forming surface, and a mask superimposed on the adhesive layer A mask layer forming step of forming a layer, and a boundary for separating adjacent semiconductor elements by irradiating the mask layer with laser light while moving the laser light relative to the semiconductor wafer on which the mask layer is formed A laser processing step for removing a mask layer and an adhesive layer in a line region; and plasma processing of a semiconductor wafer in a state where the mask layer and the adhesive layer in the boundary region are removed and a support member is attached to the circuit forming surface A plasma dicing process in which the boundary region of the semiconductor wafer is removed by plasma etching to be divided into semiconductor elements by processing. Processing method of a semiconductor wafer to be.   2. The semiconductor wafer processing method according to claim 1, wherein a thinning step of thinning the semiconductor wafer by processing the back surface is executed prior to the adhesive layer forming step.   A mask layer removing step for removing the mask layer from the adhesive layer after the plasma dicing, and an adhesive sheet attaching step for removing the support member from the circuit forming surface after the plasma dicing and sticking an adhesive sheet to the adhesive layer The method for processing a semiconductor wafer according to claim 1, comprising:   2. The method for processing a semiconductor wafer according to claim 1, further comprising a die bonding step in which the semiconductor element is peeled off from the pressure-sensitive adhesive sheet together with an adhesive layer after the pressure-sensitive adhesive sheet pasting step, and transferred and mounted on a substrate.   The semiconductor wafer processing method according to claim 1, wherein the support member is an insulating sheet.   2. The method of processing a semiconductor wafer according to claim 1, wherein the supporting member is the same size as the semiconductor wafer.   4. The semiconductor wafer processing method according to claim 3, wherein the pressure-sensitive adhesive sheet has a size larger than that of the semiconductor wafer and is fixed around by a jig.   2. The adhesive layer forming step and the mask layer forming step are simultaneously performed by attaching a sheet with an adhesive layer in which the adhesive layer and the mask layer are integrally laminated to the back surface. The semiconductor wafer processing method as described.

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