JP5599217B2 - Interdigital disc and method for manufacturing interdigital disc - Google Patents

Description

  The present invention relates to an interdigital disc and a method for manufacturing an interdigital disc.

  For example, in a semiconductor device manufacturing process, various masks and molds are used in many processes such as an etching process and a film forming process. For example, in Japanese Patent Application Laid-Open No. 61-267343 or Japanese Patent Application Laid-Open No. 4-44336, a mask having an opening corresponding to a planned division line is formed, and then the semiconductor wafer is etched through this mask to be divided. A method for forming a groove in a line is disclosed.

JP 61-267343 A JP-A-4-44336

  Such a mask is generally manufactured using a photoresist. However, it is necessary to manufacture a mask for each wafer, which is troublesome and costly.

  This invention is made | formed in view of such a point, The place made into the objective is providing the interdigital disk which can be used as a reusable mask, and its manufacturing method.

According to the first aspect of the invention, the step of forming the annular convex portion surrounding the circular recess with a manufacturing method for interdigital disc, to form a circular recess in the center portion of one surface of the disc, the Forming a plurality of through-grooves parallel to each other from the other surface of the circular plate having the circular concave portion and the annular convex portion, and forming the circular concave portion by grinding. A method for manufacturing a disk is provided.

According to invention of Claim 2 , it is a manufacturing method of the interdigital disc, Comprising: The step which forms a some mutually parallel groove | channel on the one surface of a disc, The disc by which the said some groove | channel was formed in this one surface Forming a plurality of through grooves by exposing the plurality of grooves to the circular recess by forming a circular recess at the center of the other surface and forming an annular protrusion surrounding the circular recess; and And the formation of the circular recess is carried out by grinding .

  According to the present invention, an interdigital disc that can be used as a reusable mask and a method for manufacturing the same are provided. By appropriately setting the pitch of the through grooves to be formed, it is possible to manufacture masks corresponding to wafers having different chip sizes.

It is a perspective view of the interdigital disk which concerns on this invention embodiment. It is a perspective view which shows a center part grinding process. It is sectional drawing of the disc which has a circular recessed part and the cyclic | annular convex part surrounding this circular recessed part. 4A is a cross-sectional view of a circular plate having a circular concave portion and an annular convex portion supported by an annular frame via a dicing tape, and FIG. 4B is a process of peeling back grinding tape (BG tape). FIG. FIG. 5A is a cross-sectional view showing the through groove forming process of the first embodiment, and FIG. 5B is a cross-sectional view showing the through groove forming process of the second embodiment. FIG. 6A is a partial cross-sectional view showing a half-cut process by a pre-dicing method (DBG), and FIG. 6B is a partial cross-sectional view showing a chopper-cut process by a pre-dicing method (DBG). It is a perspective view of the disc supported by the annular frame after forming a plurality of parallel grooves by the tip dicing method. It is a perspective view of the disc supported by the annular frame of the state which stuck the protective tape. It is a side view which shows a grinding process. It is sectional drawing of the state which has peeled the protective tape from the disk which has a circular recessed part and an annular convex part by grinding.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Referring to FIG. 1 (A), a perspective view of the interdigital disc 2 according to the first embodiment of the present invention is shown. The interdigital disc 2 is formed of, for example, a silicon wafer, and has a circular concave portion 4 at the center portion and an annular convex portion 6 surrounding the circular concave portion 4 at the outer peripheral portion.

  The thickness of the interdigital disc 2 in the circular concave portion 4 is, for example, 50 to 100 μm, and the thickness of the annular convex portion 6 is, for example, 600 to 800 μm. A plurality of through grooves 8 parallel to each other are formed in the circular recess 4 of the interdigital disc 2. The plurality of through grooves 8 are formed with a relatively wide pitch. The material of the interdigital disc 2 is not limited to a silicon wafer, and a compound semiconductor wafer, sapphire, glass, SiC, metal, or the like can also be employed.

  Referring to FIG. 1B, there is shown a perspective view of an interdigital disc 2A according to a second embodiment of the present invention. The interdigital disc 2A of the present embodiment has a plurality of through grooves 8 parallel to each other at a narrow pitch in the recess 4. The interdigital disc 2A is also formed of a silicon wafer, a compound semiconductor wafer, sapphire, glass, SiC, metal, or the like.

  Such interdigital discs 2 and 2A can be used as a mask that can be used repeatedly, for example, for etching a division planned line of a semiconductor wafer. Since the division lines of the semiconductor wafer are formed in a lattice shape, first, the division lines extending in the first direction are etched using the masks 2 and 2A, and then the masks 2 and 2A are rotated 90 degrees to rotate the semiconductor wafer. The dividing line that is placed on top and extends in the second direction is etched.

  By appropriately setting the pitch of the through grooves 8 to be formed, it can be used as an etching mask corresponding to semiconductor wafers having different chip sizes. Furthermore, since the masks 2 and 2A bend by forming the circular recess 4 to be as thin as 50 μm, it can also be applied to a mask for a workpiece having irregularities.

  Another method of using the interdigital discs 2 and 2A is to form the interdigital discs 2 and 2A from iron, and connect the iron interdigital discs 2 and 2A to a power source, so that the individual dicing method is used. After DAF (Die Attach Film) is attached to the rear surface of the wafer divided into the chips, this DAF can be used as a heating wire for cutting along the planned division line of the wafer.

  Furthermore, a see-through solar cell can be formed by forming a very narrow pitch through groove in the solar cell wafer to form a interdigital disk. By using the V-shaped cutting blade at the time of forming the through groove, the surface area can be increased and the conversion efficiency from light energy to electric power can be increased.

  Hereinafter, a method for forming such interdigital transducers will be described with reference to FIGS. First, as shown in FIG. 2, the grinding unit 18 of the grinding device 14 is used to form a circular recess 30 at the center of one surface of the disk 10 and surround the circular recess 30 at the outer periphery. An annular convex portion 32 is formed.

  That is, the disk 10 is sucked and held by the chuck table 16 of the grinding device 14 via the back grind tape (BG tape). The grinding unit 18 has a spindle 22 that is rotationally driven by a motor (not shown) housed in a spindle housing 20, and a wheel mount 24 is fixed to the tip of the spindle 22.

  A grinding wheel 26 having a plurality of grinding wheels 28 at its tip is detachably attached to the wheel mount 24. The grinding wheel 26 has a diameter of about half of the diameter of the disk 10 that is a workpiece.

  When a silicon wafer is used as the disc 10, the center of the disc 10 is ground while the chuck table 16 is rotated in the direction of the arrow 17 at 300 rpm, for example, and the grinding wheel 26 is rotated in the direction of the arrow 27 at 6000 rpm, for example. The circular concave portion 30 is formed in the central portion, and the annular convex portion 32 surrounding the circular concave portion 30 is formed in the outer peripheral portion. A cross-sectional view of the disk 10 after the grinding step is shown in FIG.

  After performing the grinding process, as shown in FIG. 4A, the circular recess 30 side of the disk 10 is fixed to the dicing tape 36 whose outer peripheral portion is mounted on the annular frame 34. Next, as shown in FIG. 4B, the BG tape 12 is peeled from the disk 10.

  Next, a first embodiment of the through groove forming step will be described with reference to FIG. The disc 10 in which the circular recess 30 is formed is sucked and held by the chuck table 42 of the cutting device 40 via the dicing tape 36, and the annular frame 34 is clamped by the clamp 44 to fix the annular frame 34. Thereby, the other surface of the disk 10, that is, the surface on which the circular recess 30 is not formed is exposed upward.

  In order for the chuck table 42 to suck and hold the circular recess 30 of the disk 10 via the dicing tape 36, the diameter of the chuck table 42 is preferably slightly smaller than the diameter of the circular recess 30.

  With the disk 10 sucked and held by the chuck table 42 as described above, the cutting blade 46 and the chuck table 42 are moved relative to each other in the direction of the arrow 48 while rotating the cutting blade 46 in the direction of the arrow 47, thereby A through groove having a depth that can fully cut the concave portion 30 from one end to the other end of the other surface but does not fully cut the annular convex portion 32 is formed.

  By forming a plurality of through-grooves parallel to each other while indexing the cutting blade 46 at a predetermined pitch, the interdigital discs 2 and 2A as shown in FIG. 1 can be manufactured.

  Next, with reference to FIG. 5B, the through groove forming process of the second embodiment will be described. In the through groove forming step of the present embodiment, a groove having a depth that fully cuts the circular recess 30 is formed only on the other surface corresponding to the circular recess 30 of the disk 10.

  That is, while the cutting blade 46 is rotated in the direction of the arrow 47, the cutting blade 46 is lowered in the direction of the arrow 50 and cut into the other surface corresponding to the circular concave portion 30 of the disk 10, and the cutting blade 46 and the chuck table 42 are relative to each other in the direction of the arrow 52. By moving, a through groove is formed in the circular concave portion 30, and the cutting blade 46 is raised as indicated by an arrow 54 before the annular convex portion 32. In other words, chopper traverse processing is performed.

  By performing chopper traverse processing one after another while feeding the cutting blade 46 at a predetermined pitch, a plurality of through grooves parallel to each other can be formed in the concave portion 30 of the disk 10.

  Since the interdigital disc manufactured using the chopper traverse process in this manner does not have a groove formed in the annular convex portion 32, the concave portion can be fully cut from one end to the other end of the other surface of the disc 10, but the annular convex portion 32. The strength is higher than that of an interdigital disc manufactured by forming a through-groove having a depth that does not fully cut.

  Next, with reference to FIG. 6 thru | or FIG. 10, the manufacturing method of the interdigital disk of 2nd Embodiment of this invention is demonstrated. The manufacturing method of this embodiment is a manufacturing method that employs a pre-dicing method (DBG).

  First, the half-cut groove forming step of the first embodiment will be described with reference to FIG. The disk 10 is sucked and held by the chuck table 42A of the cutting device 40, the cutting blade 46 is rotated in the direction of the arrow 47 and cut into the end of the disk 10, and the cutting blade 46 and the chuck table 42A are moved in the direction of the arrow 48. A half cut groove is formed in the disk 10 while relatively moving.

  Half-cut grooves are formed on the entire surface of the disk 10 while feeding the cutting blade 46 at a predetermined pitch. A perspective view of the disk 10 after the half-cut groove 56 is formed is shown in FIG.

  Next, with reference to FIG. 6 (B), the half cut groove | channel formation process of 2nd Embodiment is demonstrated. The half cut groove forming step of the present embodiment is performed by chopper cutting.

  That is, while rotating the cutting blade 46 in the direction of the arrow 47, the cutting blade 46 is lowered in the direction of the arrow 50 and cut inward from the end of the disk 10 by a predetermined distance. Thus, a half-cut groove is formed, and the cutting blade 46 is pulled up in the direction of the arrow 54 at a position a predetermined distance from the multiple ends of the disk 10. A plurality of parallel half-cut grooves are formed by chopper traverse cut while indexing the cutting blade 46 at a predetermined pitch.

  After completion of the half-cut groove forming step, a protective tape 58 is stuck on the disc 10 having a plurality of half-cut grooves 56 as shown in FIG. Next, the disk 10 to which the protective tape 58 is adhered is peeled from the dicing tape 36, and the protective tape 58 side of the disk 10 is sucked and held by the chuck table 16 of the grinding device 14, as shown in FIG.

  Then, similarly to the grinding step shown in FIG. 2, the circular recess 30 is formed by grinding the central portion of the disk 10 until the half-cut groove 56 is exposed, and the circular recess 30 is formed on the outer peripheral side of the circular recess 30. The surrounding annular protrusion 32 is left. Next, as shown in FIG. 10, by peeling off the protective tape 58 from the disc 50, the interdigital discs 2 and 2A as shown in FIG. 1 can be manufactured.

  In the embodiment described above, the circular concave portion 4 is formed by grinding. However, the present invention is not limited to this, and the circular concave portion may be formed by polishing or etching, for example.

  Further, the through groove forming step is not limited to cutting with a cutting blade, and the through groove may be formed by laser beam ablation processing or wetter jet processing.

2,2A Interdigital disc 4 Circular concave portion 6 Annular convex portion 8 Through groove 10 Disc 16 Chuck table 18 Grinding unit 26 Grinding wheel 30 Circular concave portion 32 Annular convex portion 34 Annular frame 36 Dicing tape 42 Chuck table 46 Cutting blade 56 Half Cut groove 58 protective tape

Claims (2)

A method of manufacturing a interdigital disc,
Forming a circular recess at the center of one surface of the disk and forming an annular protrusion surrounding the circular recess;
Comprising forming a plurality of parallel through-grooves with each other from the other surface of the disc circular recess and the annular protrusion is formed, a,
The method of manufacturing the interdigital transducer is characterized in that the circular recess is formed by grinding . A method of manufacturing a interdigital disc,
Forming a plurality of grooves parallel to each other on one surface of the disk;
A circular concave portion is formed at the center of the other surface of the disk having the plurality of grooves formed on the one surface, and an annular convex portion surrounding the circular concave portion is formed, whereby the plurality of grooves are displayed on the circular concave portion. And a step of forming a plurality of through-grooves ,
The method of manufacturing the interdigital transducer is characterized in that the circular recess is formed by grinding .

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