CS245231B1 - A method of oriented separation of silicon wafers - Google Patents

Abstract

Solution ae concerns a method of oriented division of silicon wafers with etched motifs in the production of semiconductor component systems. It uses ultrasonic drilling, where the machining tool is assembled from tubes. The glass with the cemented silicon wafer is held by blades on a support, with which it is transferred under the machining tool after being oriented according to the template on the projector screen. The template on the projector screen is adjusted according to the test drilling into the glass.

Description

(54)

Orientation of silicon wafer cutting

The solution ae relates to a method of oriented cutting of silicon wafers with etched motif in the production of semiconductor devices systems. It uses ultrasonic drilling, where the machining tool consists of tubes. The glass with cemented silicon wafer is held by the foils on the mat with which it is transferred under the cutting tool after not oriented according to the pattern on the projector screen. Set the original on the projector screen according to the test drilling in the glass.

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The invention relates to a method of oriented dividing silicon wafers into circular systems of semiconductor devices by ultrasonic drilling, the so-called bending.

Tools made of steel by drilling are used to produce systems with a centrally symmetrical structure of less than 8 mm.

The base with the locating pins is attached to the ultrasonic drill table. Always orient the base when changing the tool. Two balls inserted into the holes of the steel orientation template ensure the relative position of the tool and the template. The base is secured in position so that the position of the pins matches the corresponding holes in the template.

For self-punching, a washer with pins and a permanent magnet is used to hold the steel plate with glass coated on which the silicon plate itself is sealed. Orientation is accomplished by shifting the steel plate so that the position of the orientation pads etched on the silicon plate coincides with the position of the holes in the orientation template that is fitted to the pad pins. The plate with the plate is, after orientation, transferred to the base under the cutting tool and turned. This method cannot be used for bending with a tool made of thin-walled tubes, as they would deform in the orientation of the base.

In the manufacture of systems with an axially symmetrical structure, tools made of precision nickel tubes by brazing are used. The silicon wafer with the cut edge is bonded to the glass. An angle is used for orientation, which is placed to the edge of the plate and together with the plate to the tubes. Hold the glass with the plate when starting the ultrasonic generator. Holding the hands does not always prevent the plate from moving when the generator is switched on. Parts of boards without orientation edge cannot be processed in this way.

When systems larger than 8 mm are bent, the orientation of the plate ¹ is carried out directly according to the tool. For smaller systems, this method cannot be used for low reproducibility.

The orientation methods described do not allow the use of thin-walled tubes for bending systems with a centrally symmetrical structure of less than 8 mm. Bending by drilled tools is slower and the method used requires cementing the glass into steel plates. Quality control cannot be performed immediately after twisting. During the bending, the abrasive suspension flows into the gap between the locating pins and the corresponding ~ 3245 231 holes in the pad. Wear reduces the accuracy of orientation.

The above-mentioned disadvantages are overcome by the ultrasonic drilling method of silicon wafer according to the invention, which consists in holding glass with a silicon wafer bonded to the substrate with which it is transferred under the cutting tool after not orienting it on the projector screen. It is a further object of the invention that the adjustment of the pattern on the projector screen is carried out according to test drilling in glass. It is also an object of the invention to make it possible to use a tubular tool for bending systems with a centrally symmetrical structure less than 8 mm in diameter.

An advantage of the silicon wafer cutting method according to the invention is that it makes it possible to use cutting tools made of thin-walled tubes even for systems with a centrally symmetrical structure of less than 8 mm. This increases the number of systems from one plate, reduces the time required for twisting, reduces the consumption of the abrasive suspension, and reduces the power requirement of the ultrasonic generator. Another advantage is the simplification of the preparation of the plates prior to the actual bending, as the cementing of the glass into steel plates is eliminated. An advantage of the method of dividing silicon wafers into systems with an axially symmetrical structure according to the invention is that the number of systems from one wafers increases, since no orientation edge is required, plate fragments can also be processed, silicon wafers are not displaced when the generator is switched on. When bending systems larger than 8 ~ mm, orientation is significantly improved and facilitated.

The silicon wafer cutting process of the present invention was used to produce a triac system of 7 mm diameter. Angle 2 was clamped on the table of the ultrasonic drill 6. The same bracket was mounted on the projector's motherboard. The glass 4 used for cementing the silicon wafers was inserted under the thrust foils 6 of the washer 3 and the washer applied to the angle on the table of the ultrasonic drill 7.

After trial drilling, the glass washer was attached to the bracket on the projector motherboard. The original on the projector screen has been set and locked in position to match the image of the circled motif. The glass with cemented silicon wafer 6 was inserted under the pressure plates 4 of the washer 3. and the washer was attached to the angle on the projector base plate.

The glass with the cemented plate 6 was moved under the foils 4 of the washer 3. until the motif etched on the silicon plate matched

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X with artwork on focusing screen. After transferring and placing the pad to the angle 2 on the ultrasonic drill table, the plate was twisted.

Claims (2)

P. SCOPE OF THE INVENTION and. Method of oriented dividing of silicon plates with etched motive into circular systems of semiconductor devices by means of ultrasonic drilling, characterized in that the glass (5) with the silicon wafer (6) is held by the foils (4) on the support (3) with which according to the pattern on the projector screen, it transfers under the machining tool, which is made of tubes. 2. A silicon wafer cutting method according to claim 1, characterized in that the setting of the original on the projector screen is performed according to the test drilling in the glass.