JPS63301543A - Manufacture of semiconductor element - Google Patents

Abstract

PURPOSE:To protect pellets from cracks or warp for improvement in their voltage-withstanding capability and for the attainment of a good yield by a method wherein a laser beam is applied to produce grooves in a heated semiconductor element wafer provided with P-N junctions for segmentation into a plurality of pellets. CONSTITUTION:A laser device 7 emits a laser beam 1, which lands on a segmentation line A or B in a semiconductor element wafer 2. The semiconductor element wafer 2 is fixed secure in a supporting bed 4, turns around in a direction 8 at a prescribed rate, and is subjected to segmentation by the laser beam 1. The supporting bed 4 is provided with a heater 3, which heats the entirety of the semiconductor element wafer 2. In this way, a semiconductor element wafer is protected from cracks or warp and is improved in its voltage- withstanding feature, which ensures a better yield.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for manufacturing a semiconductor device, and more particularly to a processing method for dividing a semiconductor device phenol into pellets using laser light.

[Conventional technology]

Conventionally, when dividing this type of semiconductor element into individual pellets using a laser beam, the conditions were controlled to the optimum by controlling the power and frequency of the laser beam, the rotation of the object to be cut, the stroke speed, etc. The method used was to apply the material to a quartz to create grooves and then cut and divide it.

[Problem that the invention seeks to solve]

In the above-mentioned conventional cutting of a semiconductor element wafer using a laser beam, the part of the semiconductor element wafer that is irradiated with the laser beam is melted by the energy of the laser beam, and the semiconductor element wafer is rotated or reciprocated to create a designated area. Grooves are made in the shape and separated into individual pellets. However, conventional cutting methods using laser light cut semiconductor element wafers at room temperature, which can cause cracks and warpage due to the rapid temperature rise caused by laser light irradiation or the temperature difference between the sides and the center of the pellet due to melting. was. Cracks and warping of this pellet are due to the characteristics of semiconductor elements.
This is a factor that reduces the withstand voltage or current capacity, leading to lower product yields and contributing to higher costs.

[Means for solving problems]

The feature of the present invention is that it has a device that heats the semiconductor element wafer at room temperature, which raises the semiconductor element wafer to a certain temperature and promotes the degree of melting by laser light. The grooves are created using a laser beam while ensuring uniform temperature distribution to avoid any effects.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

FIG. 1 shows an embodiment of the present invention, in which a laser device 1 is shown.
Laser light 1 is emitted from 7 and irradiated onto the cut portion A or iB of the semiconductor element wafer 2. The semiconductor cable wafer 2 is tightly fixed on a support 4 9 and rotated at a constant rotational speed in the rotational direction 8 indicated by the arrow by a drive device rIt (not shown), and is cut by the laser beam 1 .

It has a structure that warms the whole body.

FIG. 3 shows the temperature distribution of the semiconductor element wafer 2 due to irradiation with one laser beam, and the temperature at the cutting part A or B is high, but according to the present invention, the temperature difference is small as shown by the solid line C, and the temperature distribution of the conventional technology is shown by the dotted line. Compared to E, it has less influence on semiconductor elements.

FIG. 4 is a partially enlarged view of another embodiment of the present invention. The heating elements 6 built into the support base 4 are individually set to 8. When the semiconductor element wafer 2 is completely divided, the heating elements 6 are separated so that reciprocating movement, that is, linear movement is possible. There is an advantage that the temperature distribution of the conductor element wire wafer 2 can be adjusted and cutting can be performed under the best conditions.

〔Effect of the invention〕

As explained above, in the present invention, by heating the semiconductor element wafer 2, cracks and warping of the semiconductor wafer 2 after being melted and cut by the laser beam 1 can be avoided. Therefore, the withstand voltage of the electrical characteristics of the semiconductor element and the yield rate of the laser heating process are improved, and the cost can be reduced.

[Brief explanation of drawings]

FIG. 1 is a partial sectional view of laser cutting according to an embodiment of the present invention, and FIG. 2 is an enlarged sectional view of a portion of FIG. 1 that heats the semiconductor element wafer. FIG. 3 is a graph showing the temperature distribution of the semiconductor wafer of the present invention and the conventional semiconductor wafer due to laser light. FIG. 4 is a partial sectional view showing another embodiment of the present invention. 1...Laser light, 2...Semiconductor cable wafer, 3...Heating element, 4...Support stand, 5...Escape Groove, 6... Heating element, 7.
...Laser device, 8...Rotation direction, A
... Cutting part, B ... Cutting part, C...
...Temperature distribution of the semiconductor element wafer of the present invention, E...
...Temperature distribution of conventional semiconductor device wafer, D
...Temperature distribution of semiconductor device wafer. Figure 1 Figure 2

Claims (1)

[Claims] A method for manufacturing a semiconductor device, which comprises forming grooves using a laser beam while heating a semiconductor device wafer having a PN junction, and dividing the semiconductor device wafer into a plurality of pellets.