JPH0121622B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an automatic punching device for protecting a semiconductor wafer.

Semiconductor wafers (0.2 to 0.25 mm thick) are fragile as they are, so a mount is attached to the bottom of the semiconductor wafer and a protective film such as vinyl is attached to the top to prevent damage during handling. Usually, a protective film larger than the semiconductor wafer is placed on the top surface of the semiconductor wafer, and the protective film is cut out along the periphery of the semiconductor wafer to attach the protective film to the semiconductor wafer. Conventionally, the protective film was cut out along the periphery of the semiconductor wafer by hand using a knife. The manual process was due to the difficulty of accurately setting the protective film on the semiconductor wafer at the cutting position.
This is because the impact on the semiconductor wafer caused by the cutting tool may lead to destruction of the semiconductor wafer.

An object of the present invention is to provide an apparatus that automatically punches out the protective film of such a semiconductor wafer and efficiently covers the semiconductor wafer with the protective film.

Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a schematic diagram of an automatic punching device for a protective film of a semiconductor wafer according to the present invention, and shows a position detection state of a semiconductor wafer.

A semiconductor wafer 19 is placed on the X table 1, and the position of the semiconductor wafer 19 is detected by the sensor 18 of the position detector 5. In response to the signal from the sensor 18, the control device 13 controls the X-direction table 1, the Y-direction table 1,
A drive pulse signal is sent to the drive pulse motors 14, 15, and 16 of the direction table 2 and the rotary table 3 to gradually move the semiconductor wafer 19 in the orthogonal direction and the rotational direction, thereby accurately centering and orienting the wafer 19. stipulate. To detect the position, an optical sensor 18 is used to detect the peripheral edge of the semiconductor wafer. However, since this peripheral edge is covered with a vinyl film, the corners of the peripheral edge are gently sloped, making it difficult to detect their positions. For this reason, in this embodiment, a light emitting element such as a light emitting diode is used to illuminate the periphery of the semiconductor wafer, and the reflected light is detected by the optical sensor 18, thereby achieving accurate position detection.

When the semiconductor wafer 19 is set at a predetermined position, the control device 13 starts supplying working fluid to the cylinder 17 and causes the piston rod 4 to retreat by a certain distance A. When the piston rod 4 is retracted by a certain distance A, the punching device 6, which is fixed to the piston rod 4 at a distance A from the detector 5, is positioned above the semiconductor wafer 19.

FIG. 2 shows the automatic punching device in the state of punching out the protective film. The punching device 6 is a semiconductor wafer 1
9, the control device 13 operates a first pneumatic actuation system (not shown) to supply compressed air to the enlarged end of the cylinder 7 of the punching device 6 through the air passage 8 of the cylinder 7. 9 and the lower end of the enclosure 10 to expand this space and push down the enclosure 10;
The punching tool 12 is pressed around the semiconductor wafer 19 to punch out the vinyl thin film of the semiconductor wafer 19. If the hole at the lower end of the enclosure 10 through which the guide pin 20 is passed is made somewhat larger than the diameter of the guide pin 20, air will leak downward from the hole and the semiconductor wafer 19 will be fixed on the X table 1. Instead of enlarging the hole of the guide pin 20, a small hole (not shown) may be made at the lower end of the enclosure 10 to allow air for fixing the semiconductor wafer 19 to flow out. If negative pressure is applied and suction is applied, the semiconductor wafer 19 placed on the mount will often be damaged by the uneven force applied to it.)

Next, the controller 13 operates a second pneumatic actuation system (not shown) to connect the enlarged end 9 and the enclosed end 10 of the barrel 7.
The punching tool 12 is separated from the semiconductor wafer 19 by sending compressed air between the punching tool 12 and the top end of the envelope 10 to push up the top end of the enclosure 10 . In this case as well, air flowing through a small gap between the guide pin 20 at the lower end of the enclosure and the hole through which the guide pin 20 passes blows the semiconductor wafer off the punching tool.

The semiconductor wafer has a notched circle with a portion cut out to serve as an alignment index, and the punching tool 12 is a punching blade that has the same shape as this notched circle but is slightly larger.

If the semiconductor wafer 19 is particularly thin, the wafer may break due to the tension applied to the vinyl during cutting by the punching blade. Destruction of the wafer can be avoided by using the punching blade as a double-edged blade tapered from both sides, or in the case of a single-edged blade with a taper on one side, by using the punching blade with the tapered side facing the wafer.

[Brief explanation of drawings]

FIG. 1 is a schematic side view of an embodiment of the invention, shown in alignment. FIG. 2 is a view similar to FIG. 1, but in a punched state. In the diagram: 1: X table, 2: Y table, 3:
rotary table, 4: piston rod, 5: detector, 6: punching device, 7: cylinder, 8: air flow path,
9: Expansion end, 10: Enveloping body, 11: Chuck, 1
2: Punching tool, 13: Control device, 14; 15;
16: Drive pulse motor, 18: Optical sensor, 1
9: Semiconductor wafer, 20: Guide pin.

Claims (1)

[Claims] 1. An X-Y table that can move orthogonally and rotate; A piston rod that can reciprocate a certain distance on this X-Y table; A piston rod that is fixed to this piston rod. a semiconductor wafer position detector; a punching device fixed to the piston rod at a distance from the position detector; and a control device, the punching device being fixed to the piston rod and connected to an air flow path. a cylinder having an enlarged end; an enclosure surrounding the cylinder in airtight contact with the enlarged end of the cylinder and slidingly secured to the cylinder; a punching tool at the lower end of the enclosure; means for removably securing the body; a first pneumatic actuation system for directing air through said air passageway between the enlarged end of the barrel and the lower end of the envelope end to push down the envelope; and a second pneumatic actuating system for pushing up the enclosure by sending air between the upper end of the enclosure and the upper end of the enclosure; moving the piston rod, actuating the first pneumatic actuating system to punch the protective membrane of the wafer, actuating the second pneumatic actuating system to push up the enclosure, and moving the piston rod in the opposite direction. 1. An automatic punching device for a protective film of a semiconductor wafer, characterized in that the position detector is moved on the X-Y table. 2. The automatic punching device for a protective film of a semiconductor wafer according to claim 1, wherein the position detector includes a light sensor and a light emitting element for detecting the position of the semiconductor wafer. 3. The automatic punching device for a protective film of a semiconductor wafer according to claim 1, wherein the lower end of the enclosure has an air leak hole.