JP3339231B2 - Method for manufacturing semiconductor device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a semiconductor device in which a laminated semiconductor wafer having a pn junction is cut into a rectifier.

[0002]

2. Description of the Related Art A running system for displaying a television screen.
A power supply unit for controlling the scanning requires a high voltage, and a high voltage diode having a withstand voltage of several kV to several tens kV is required to generate the high voltage. This high voltage diode is pn
Laminated semiconductor wafer with solder layer
And, to such a columnar body by cutting the stacked wafers, the
Rear cut surface is chemically treated, leads attached to both ends of the columnar body is produced by coating the coercive Mamorumaku. A conventional manufacturing process will be described. FIGS. 4A and 4B show a state in which the semiconductor wafer fixed to the support jig is cut, and FIG. 4A is a plan view and FIG. 4B is a sectional view. semiconductor wafer 10 having a pn junction, the solder layer 3 or aluminum and is next laminated body 1 integrally laminated via an alloy layer of silicon, one of the entire surface of the laminate 1 to the support jig 4 are bonded, a blade saw ( It is cut into square pillars 2 of about 1 mm square by a disc-shaped saw) or a wire saw (steel wire saw). afterwards,
The columnar body 2 in the outer peripheral portion is not square but partly circular, and becomes a defective columnar body 22 having a defective shape. A support jig 4 is used to connect the square non-defective columnar body 21 and the defective columnar body 22 at the inner peripheral portion of the laminate 1 to each other.
While peeling off from sort out sorting work is Ru need der.

[0003]

[Problems that the Invention is to Solve Since this sorting work is visually work with a microscope, defects pillars 22 is mixed into non-columnar body 21 around the next step, <br/> each until the defect pillars 22 In addition to performing the processing in the manufacturing process, there is a waste that a step of determining a defect again in the final inspection is necessary . In addition, a large amount of human labor is required for the visual sorting operation, which causes a disadvantage of increasing the manufacturing cost.

An object of the present invention is to solve the above-mentioned problems and to provide a method of manufacturing a semiconductor device which eliminates the need for a visual sorting operation.

[0005]

SUMMARY OF THE INVENTION In order to achieve the above object, after a plurality of semiconductor wafers having a pn junction are formed in a laminate formed by laminating a solder layer or an alloy layer of aluminum and silicon. In a semiconductor device having a columnar body obtained by cutting into a square, a lead wire, and a bonding coating film, an inner periphery in which the shape of the columnar body becomes good after cutting the laminated body
Attach the support jig to the part, and after cutting the laminate , the columnar body shape
A step is provided on the outer peripheral portion of the supporting jig corresponding to the outer peripheral portion to be defective so that the stacked body is not bonded, and the outermost end of the supporting jig is aligned with the outermost end of the semiconductor wafer, and the stacked body is positioned. It is effective to combine and cut the laminate. Further, the laminate is preferably bonded to a support jig having the same size as the inner peripheral portion having a good columnar shape after cutting the laminate, and the laminate is preferably cut. Further, when the size of the inner peripheral portion of the laminated body to be bonded to the support jig is made smaller by 1 mm to 3 mm than the diameter of the laminated body, the defective columnar body is surely selected. And the support jig is made of glass
It is good to

[0006]

When the laminated body of the laminated semiconductor wafer is adhered to the supporting jig only at the inner periphery thereof and cut like a grid to form a square pillar, the outer periphery of the laminated body is partially formed. It becomes an arc-shaped columnar body, and becomes a columnar body having a poor shape. Since this defective columnar body does not adhere to the support jig, it is separated from the support jig when cutting, and only a square non-defective columnar body remains adhered to the support jig and is visually observed by separating this from the support jig. Can be easily sorted without relying on. By bonding only the inner periphery of the laminate that will be a good columnar body to this support jig and providing a step at the portion of the support jig corresponding to the outer periphery, the exudation of the adhesive material when attaching the laminate is absorbed And when cut, the defective columnar body can be easily separated from the support jig. Further, since the cross section of the columnar body is about 0.5 mm to 1 mm, if the size of the portion of the support jig that is bonded to the laminate is smaller by 1 to 3 mm than the outer peripheral end of the laminate, the defective columnarity can be reliably replaced with a good columnar body. , And can be easily and reliably sorted.

[0007]

1 is a sectional view of a first embodiment of the present invention. FIG. 1 (a) is a sectional view before cutting, and FIG. 1 (b) is a sectional view after cutting. The plan view after cutting is the same as that in FIG. The laminated body 1 in which the semiconductor wafer 10 having the pn junction is laminated via the solder layer 3 is placed on a glass support jig 4 and bonded with an adhesive 5. The support jig 4 is bonded at the inner peripheral portion 7 of the laminate 1, and the outer peripheral portion 8 has a thickness of 0.1 mm.
By forming a step 6 of about 5 mm to 1 mm on the support jig 4, no contact occurs. The step 6 also serves as a clearance for the adhesive 5. The laminate 1 can be positioned by matching the diameter of the support jig 4 with the laminate 1. Next, the laminated body 1 is cut into a columnar body 2 by cutting the laminated body 1 into a square of about 1 mm square using a wire saw. The contaminants such as cutting powder adhered after cutting and oil for preventing heat during cutting are removed with an organic solvent of DMF (dimethylformamide), and the laminate 1 is washed. Further, since the outer peripheral end of the laminated body 1 is circular, the cross-sectional shape of the columnar body 2 cut at the outer peripheral part of the laminated body 1 is not a perfect square but a partly circular shape, and the defective columnar body 22 having a poor shape is formed. Become. Since the outer peripheral portion 8 is not adhered to the support jig 4, it is separated from the non-defective columnar body 21 at the time of cutting and washing, and is automatically sorted. In addition, by reducing the size of the inner peripheral portion 7 serving as the bonding portion of the support jig 4 by 1 mm to 3 mm from the outer peripheral end of the stacked body 1, the defective columnar body 22 can be reliably sorted out.

FIG. 2 is a sectional view of a second embodiment of the present invention. The laminated body 1 is bonded to a glass support jig 4 having a diameter of 1 mm to 3 mm smaller than the diameter of the laminated body 1 with an adhesive 5 and cut. By using a column for the support jig 4, the same effect as in the first embodiment can be obtained. FIG. 3 shows a sectional view of a third embodiment of the present invention. A support jig 4 having the same diameter as the laminate 1 is 1 mm to 3 mm smaller than the outer peripheral end of the laminate 1 and has a width of 0.5 m.
Drill a groove 9 of about 1 mm with a width of about m. The groove 9 serves as a clearance for the adhesive 5. The adhesive 5 is applied to the inside of the groove 9 of the support jig 4 and the portion of the laminate 1 including only the non-defective columnar body 21 is adhered. Thereafter, the laminate 1 is cut with a wire saw, and the defective columnar body 22 that is not adhered is separated and sorted.

[0009]

According to the present invention, an inner peripheral portion having a good columnar shape after cutting a laminated body obtained by laminating semiconductor wafers having pn junctions is bonded to a supporting jig, and then cut into a square, and bonded to the supporting jig. The columnar body having a poor shape at the outer peripheral portion can be separated from the non-defective columnar body at the time of cutting, and can be sorted out without visual selection. For this reason, it is possible to eliminate the problem that the defective columnar body is mixed with the nondefective columnar body, which has been conventionally visually selected, and it is possible to eliminate various wastes in the process due to the mixed columnar body.

[Brief description of the drawings]

FIG. 1 shows a cross-sectional view of a first embodiment of the present invention, wherein (a)
Is a sectional view before cutting and (b) is a sectional view after cutting.

FIG. 2 is a sectional view of a second embodiment of the present invention.

FIG. 3 is a sectional view of a third embodiment of the present invention.

4A and 4B show a conventional configuration diagram, wherein FIG. 4A is a plan view and FIG.
Is a sectional view

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Laminated body 2 Columnar body 21 Non-defective columnar body 22 Defective columnar body 3 Solder layer 4 Support jig 5 Adhesive material 6 Step 7 Inner peripheral part 8 Outer peripheral part 9 Groove 10 Semiconductor wafer

──────────────────────────────────────────────────の Continued on front page (51) Int.Cl. ⁷ Identification code FI H01L 29/91 A

Claims (4)

(57) [Claims] 1. A columnar body and a lead wire obtained by forming a plurality of semiconductor wafers having a pn junction in a laminated body laminated via a solder layer or an alloy layer of aluminum and silicon and then cutting the same into a square. In the semiconductor device having the semiconductor device and the bonding coating film, the shape of the columnar body is good after cutting the laminate.
Glue a support jig to the inner periphery of the
On the outer periphery of the support jig corresponding to the outer periphery where the shape is defective
Provide a step so that the laminate does not adhere, and
Align the laminate by aligning the outermost edge with the outermost edge of the laminate.
And cutting the stacked body. 2. A semiconductor device comprising a plurality of semiconductor wafers having a pn junction.
Via a solder layer or an alloy layer of aluminum and silicon
And then cut into squares
Semiconductor having obtained columnar body, lead wire and bonding coating film
In the body device, the columnar shape is good after cutting the laminate.
The inner peripheral portion identical to adhere the laminate to the size of the support jig and the method of manufacturing a semi-conductor device characterized by cutting the laminate that. 3. The method for manufacturing a semiconductor device according to claim 1 , wherein the size of the inner peripheral portion of the laminate bonded to the support jig is smaller by 1 mm to 3 mm than the diameter of the laminate. 4. A method of using a support jig made of glass.
The method for manufacturing a semiconductor device according to claim 1 .