JPH0457663A - Positioning mechanism in prepositioning automatic surface grinder - Google Patents

Abstract

PURPOSE:To smoothly position and take out a semiconductor wafer by floating up the semiconductor wafer mounted on a wafer mount with water supplied liquid and pouring the liquid out of an outflow edge to bias the semiconductor wafer to wafer positioning edge for positioning it. CONSTITUTION:A semiconductor wafer A mounted on a wafer mount 7 begins to float up with water supplied liquid. When the water level rises above a flowout edge 8c, the liquid overflows from the outflow edge 8c to produce water flow toward a wafer positioning edge 8b. Thus, the semiconductor wafer A is moved horizontally toward the wafer positioning edge 8b and the periphery of the semiconductor wafer A abuts against the wafer positioning edge 8b to stop horizontally and complete the positioning in the position shown by the solid line. Under such conduction, the upper surface of the semiconductor wafer A is sucked by an sucking pad provided on a transfer arm. Then, the surface tension of the liquid is broken to take out the wafer A.

Description

[Detailed Description of the Invention] [Technical Field] The present invention provides a method for cleaning the lower surface of a semiconductor wafer with a water stream in a preposition stage before transferring the semiconductor wafer to the upper surface of a chuck mechanism for grinding the semiconductor wafer, such as in a surface automatic grinding machine. It also relates to a mechanism for positioning on the preposition.

[Background of the invention]

This type of semiconductor wafer according to the present invention is used for integrated circuits in electronic equipment such as computers, so-called office automation equipment, etc., and the development thereof is progressing day by day, and as the equipment itself becomes smaller, There is a growing demand for larger diameters due to ultra-thin, ultra-high precision quality and improved workability.

[Prior art and its problems]

This type of surface automatic grinder sucks the semiconductor wafer onto the flat surface of a chuck mechanism with a vacuum suction function, and then lowers a spindle shaft with a diamond grinding wheel at the tip from above to perform the grinding process. After that, air is sent backwards to release the vacuum suction, and a transfer arm with a suction bat at the tip is used to suction the wafer, transport it, clean it, and store it.The semiconductor wafer is aligned during the grinding process. This is done either directly on the chuck mechanism, or prepositioned before being transferred to the chuck mechanism.

However, when positioning is performed on a flat chuck mechanism, a suitable water layer is formed on the entire top surface of the chuck mechanism with oil and water, and the surface tension of the water layer is used to center the chuck mechanism to the center position. In order to form an appropriate water layer, the amount of water must be constantly controlled, and in addition, forming the water layer, centering it, and vacuum adsorption are time-consuming processes.

In addition, when positioning is to be performed in pre-position, a disc-shaped base body having an edge on the outer periphery is provided, and a positioning guide is provided in advance such as forming a taper on the periphery. The semiconductor wafer is aligned along the wafer, and is adsorbed with a suction bat provided at the tip of the transfer arm, and water is supplied from below the bottom of the substrate to clean the bottom surface of the semiconductor wafer while floating it and raising the transfer arm. The semiconductor wafer is peeled upward from the top surface of the substrate, and the semiconductor wafer is accurately transferred to the center of the top surface of the chuck mechanism by a precisely set transfer process of the transfer arm. Semiconductor wafers, which are becoming extremely thin and enlarged in diameter, have had problems such as frequent accidents that damage the semiconductor wafers due to the adsorption effect due to the characteristics of the liquid retained in the substrate.

[Purpose of the invention]

In view of the above-mentioned reasons, the present invention has been made as a result of extensive research, and in these prepositions, the outer peripheral edge of the base body on which the semiconductor wafer is mounted is divided into a wafer take-out side edge, a wafer positioning edge, and an outflow edge. By creating a flow of water as the water level rises due to water supply, semiconductor wafers can be smoothly aligned and removed, and even semiconductor wafers that are becoming thinner and larger in diameter can be prevented from being affected by the adsorption effect of liquid. It is an object of the present invention to provide a pre-position alignment mechanism that can be transferred to an accurate position on a chuck mechanism without being damaged by damage.

[Structure of the invention]

The structure of the present invention is to provide a central member protruding from the disc-shaped body, drill a water supply hole that penetrates the central member and the base, install an annular stopper on the inner periphery of the water supply hole, and connect a support pipe to the water supply hole. A water supply control member having a body portion and a flow rate control hole is inserted into the annular stopper in contact with the annular stopper, and a water supply control member having a body portion and a flow rate control hole is inserted into the annular stopper with a gap portion, and a plurality of small water flow holes are inserted into the gap portion. A disk-shaped wafer mounting table is provided at the top, an annular member is fitted to the outer periphery of the base, and a wafer take-out side edge is formed at more than half the outer periphery of the annular member. , a plurality of wafer positioning edges are erected on the outer peripheral edge of the other side, and an outflow edge is formed between the respective wafer positioning edges.

[Embodiments of the invention]

An embodiment of the positioning mechanism for pre-positioning, etc. of the automatic surface grinding machine of the present invention that achieves the above object will be explained below with reference to the drawings. Fig. 1 shows the positioning mechanism of the automatic surface grinding machine according to the embodiment of the present invention. FIG. 2 is a schematic plan view for explaining the eyelids, and FIG. 2 is a schematic cross-sectional view taken along the center line.

The present invention cleans the bottom surface of the semiconductor wafer A with a water stream and aligns it on the preposition at the same time as cleaning the bottom surface of the semiconductor wafer A with a water stream in a preposition stage before transferring the semiconductor wafer A to the top surface of a chuck mechanism that grinds the semiconductor wafer A in an automatic surface grinder. In the preposition of the surface automatic grinding machine, a cylindrical center member 2 is provided protruding from the lower surface of the center side of the disk-shaped base 1, and the center of the center member 2 and the base 1 is A water supply hole 3 is drilled through the part, and the water supply hole 3 is
An annular stopper 4 having a vertical cross-section is planted at a height slightly higher than the lower end on the inner periphery of the water supply hole 3, and a support pipe 5 for water supply is brought into contact with the annular stopper 48 from below into the water supply hole 3. A water supply control member 6 having a short cylindrical body 6a and a flow rate control hole 6b inside is inserted above the annular stopper 4 and has a gap slightly higher than the bottom surface of the base 1. and insert it into the
A plurality of small water passage holes 6c communicating with the flow rate control holes 6b are bored in the spaced portion, and a disk-shaped wafer mounting table 7 is installed at the top of the body 6a around the outer periphery of the body 6a. At the same time, an annular edge member 8 is fitted onto the outer periphery of the base 1, and a constant water level is maintained above the wafer mounting table 7 over at least half of the outer periphery of the annular edge member 8. A wafer take-out side edge 8a is formed as high as possible, and a plurality of wafer alignment edges having an upper end higher than the upper end of the wafer take-out side edge 8a and a space between them are formed on the other side outer peripheral edge. 8b is erected along the outer peripheral edge, and the upper end of the outflow edge 8c is connected to the upper surface of the wafer mounting table 7 and the upper end of the wafer take-out side edge 8a between the respective wafer positioning edges 8b. By forming the semiconductor wafer A at a position between the two, the semiconductor wafer A mounted on the wafer mounting table 7 is floated by the liquid supplied with water, and the liquid flows out from the outflow edge 8c, so that the semiconductor wafer A is
The wafers are aligned by bringing them closer to the plurality of wafer alignment edges 8b.

That is, the automatic surface grinding machine embodying the present invention includes a chuck mechanism for grinding the semiconductor wafer A, and a mechanical setting mechanism for placing the semiconductor wafer A at an accurate position from a pre-position on the chuck mechanism. A transfer arm that can be raised and lowered and moved back and forth on a precise trajectory, and a suction bat (not shown) that can adsorb and detach the upper surface of the semiconductor wafer A provided at the tip of the transfer arm. It has been established,
The positioning mechanism of the present invention is for positioning the semiconductor wafer A at a pre-position of the disc-shaped base 1 before the semiconductor wafer A is transferred by the transfer arm. A center member 2 is formed to protrude downward, and a water supply hole 3 is bored through the center of the center member 2 and the base 1, and the water supply hole 3 is connected to an annular stopper 4 to be described later. A control member 6 is housed inside, and the lower end side serves as a connection part with the support tube 5.

The annular stopper 4 has an annular portion having a slight height and a horizontal portion that bulges out like a flange toward the lower end of the annular portion. A horizontal groove is formed in the circumferential direction on the inner surface of the water supply hole 3, and the horizontal portion is planted in the groove, and the annular portion is slightly spaced from the inner circumference of the water supply hole 3.

From below, the water supply hole 3 is connected to a water supply pump and a support pipe 5 that supports the bridge position.
The upper end is brought into contact with the lower end of the stopper 4 and fitted,
From above the water supply hole 3, there is a short cylindrical body 6 that opens downward.
The lower end of the body portion 6a of the water supply control member 6 having the shape A is brought into contact with the upper end of the horizontal portion of the stopper 4, and the upper side of the body portion 6a is inserted into the above-mentioned slight interval.

The water supply control member 6 has the upper side of the body 6a protruding from the bottom surface of the base 1 by a slight height, and has a circle having a size sufficient to place the semiconductor wafer A on the upper end of the body 6a. A plate-shaped wafer mounting table 7 is formed by protruding from the outer periphery of the body 6a, a partition is formed inside the body 6a to control water flow, and a water flow control hole 6b is formed in the partition. The upper side of the body 6a directly below the wafer mounting table 7 has a plurality of water passages /J connected to the water flow control hole 6b.
) The holes 6c are arranged radially.

An annular member 8 serving as an edge is fitted onto the outer periphery of the base 1, and at least half the circumference of the annular member 8 has a height that allows a constant water level to be maintained above the wafer mounting table 7. A wafer take-out side edge 8a is formed, and a plurality of wafer alignment edges 8b each having an upper end higher than the upper end of the wafer take-out side edge 8a and a space between them are formed on the other side outer peripheral edge. The upper end of the outflow edge 8c is positioned at the upper surface of the wafer mounting table 7 and the upper end of the wafer take-out side edge 8a, and is formed in the interval between the respective wafer positioning edges 8b. It is something.

With the above-described configuration, the semiconductor wafer A mounted on the wafer mounting table 7 is floated by the liquid supplied with water, and the liquid is caused to flow out from the outflow edge 8c, thereby aligning the semiconductor wafer A with a plurality of wafers. The positioning is performed by bringing it closer to the edge 8b.

In the present invention, first, an extremely thin and enlarged semiconductor wafer A to be suctioned and placed on a vacuum chuck mechanism and subjected to a grinding process is transferred to the substrate 1 by a transfer device (not shown).
The wafer is placed on the wafer mounting table 7, and the water supplied from the inside of the support tube 5 by operating the water supply pump in advance passes through the water supply hole 3 and flows through the flow rate control hole 6b of the water supply control member 6.
The amount of water is controlled to a constant amount through a plurality of radially arranged small water passage holes 6c and remains in the space surrounded by the upper surface of the substrate 1 and the outer peripheral member 8, and the semiconductor When the wafer A is placed on the top surface of the wafer mounting table 7 with some force, the remaining liquid overflows from each outflow edge 8c and flows out, and at the same time, the fine particles attached to the bottom surface of the semiconductor wafer A are removed. Any dust etc. will be washed away.

Furthermore, as the water supply continues, the semiconductor wafer A begins to float uniformly, and when the water level rises above the outflow edge 8C, the liquid overflows from the outflow edge 8c and flows out to the wafer alignment edge 8b. Accordingly, the semiconductor wafer A moves horizontally in the direction of the wafer alignment edge 8b, and the peripheral edge of the semiconductor wafer A comes into contact with the wafer alignment edge 8b, causing the semiconductor wafer A to move horizontally toward the wafer alignment edge 8b. The transfer arm stops in this state, and the alignment is completed at the position shown by the solid line in the figure. In this state, the top surface of the semiconductor wafer A is suctioned by a suction bat provided on the transfer arm.

Further, when the water supply is continued, the water level reaches the upper end of the wafer take-out side edge 8a due to water supply, and the forward and backward movement mechanism of the transfer arm moves the semiconductor wafer from the wafer alignment edge 8b direction to the wafer take-out side edge 8a. The device removes sea urchins/sea urchins by moving horizontally in the direction of
) The transfer arm can be removed from the direction of the take-out edge 8a, and the transfer arm moves along a precise trajectory to be transferred to a precise position on the upper surface of the chuck mechanism.

〔Effect of the invention〕

As described above, the present invention not only allows semiconductor wafers to be removed even if they are becoming extremely thin and enlarged in diameter without being affected by the adsorption effect of water, but also enables accurate positioning. By increasing the amount of water, positioning can be done quickly, and its contribution is immeasurable, making it an extremely significant invention.

[Brief explanation of the drawing]

FIG. 1 is a schematic plan view for explaining preposition in a positioning mechanism of an automatic surface grinding machine according to an embodiment of the present invention. FIG. 2 is a schematic sectional view taken along the center line. A-Semiconductor wafer. 1-base, 2-center member, 3-water supply hole, 4-stopper 5-support pipe, 6-water supply control member, 6a-body, 6b-
Flowing water control hole, 6c- water passage small hole, 7- wafer mounting platform, 8-
Outer peripheral edge member, 8a-wafer removal side edge, 8b-wafer positioning edge, 8C-outflow edge.

Claims (1)

[Claims] In the preposition of a surface automatic grinding machine, a cylindrical center member is protruded from the lower surface of the center side of the disk-shaped base.
Drilling a water supply hole penetrating the center member and the center of the base,
An annular stopper having an L-shaped longitudinal section is planted on the inner periphery of the water supply hole at a height slightly higher than the lower end, and a support pipe for water supply is inserted into the water supply hole from below by contacting the annular stopper. A water supply control member having a short cylindrical body and a flow rate control hole therein is fitted above the annular stopper with a gap slightly higher than the bottom surface of the base, and A plurality of small water holes communicating with the flow rate control holes are bored in the body, and a disk-shaped wafer mounting table is provided at the top of the body so as to bulge out from the outer periphery of the body. , an annular edge member is fitted onto the outer periphery of the base body, and a wafer take-out side edge is formed at least half the circumference of the outer periphery of the annular edge member at a height that can maintain a constant water level above the wafer mounting table. A plurality of wafer positioning edges are provided along the outer periphery of the other side, each having an upper end higher than the upper end of the wafer removal side edge and a gap between each wafer alignment edge. The gap between the wafer alignment edges is formed by locating the upper end of the outflow edge between the upper surface of the wafer mounting table and the upper end of the wafer take-out side edge. An automatic surface grinding machine characterized in that a semiconductor wafer placed on a surface is floated by liquid supplied with water, and the liquid is flowed out from an outflow edge to bring the semiconductor wafer to a wafer alignment edge for alignment. Alignment mechanism in pre-position.