KR20000043451A - Chemical mechanical polishing apparatus with location alignment part - Google Patents

Abstract

PURPOSE: A chemical mechanical polishing apparatus with a location alignment part is provided to flatten a surface of a semiconductor by loading automatically a semiconductor wafer. CONSTITUTION: A chemical mechanical polishing apparatus with a location alignment part comprises a load station(11), a spray box(20), a polishing head portion(16), a first transfer portion(12), and a second transfer portion(14). The load station loads a wafer cassette(8) for receiving a plurality of semiconductor wafer(7). The spray box receives the semiconductor wafer and sprays pure water on the semiconductor wafer. The polishing head portion polishes a surface of the semiconductor by a mechanical friction. The first transfer portion transfers the wafer between the load station and the spray box. The second transfer portion transfers the wafer between the spray box and the polishing head portion. The chemical mechanical polishing apparatus further comprises a location alignment part for aligning operation locations of the first and the second transfer portions.

Description

CMP apparatus having means for aligning location

The present invention relates to an apparatus for manufacturing a semiconductor wafer having an integrated circuit, and more particularly, to a chemical mechanical polishing apparatus for automatically loading a semiconductor wafer to planarize the surface of the semiconductor wafer.

Chemical Mechanical Polishing (CMP) is a technique of planarizing the surface of a semiconductor wafer through chemical and mechanical reactions. The principle is to supply a slurry while bringing the semiconductor wafer into contact with the polishing pad surface to chemically react the surface of the semiconductor wafer, while the table on which the polishing cloth is attached and the wafer carrier to which the semiconductor wafer is attached (or Relative movement of the wafer holder to physically planarize the uneven portion of the surface of the semiconductor wafer.

Usually, the equipment for performing the chemical mechanical polishing process is composed of the upper head (or wafer head) for fixing the wafer and the lower head for supplying slurry and attaching the polishing cloth to the basic unit. A load station on which a semiconductor wafer is waiting, a transfer means for transferring semiconductor wafers between respective unit devices, a spray box for preventing drying of the semiconductor wafer, and the like are provided.

1 is a schematic configuration diagram of a chemical mechanical polishing apparatus according to the prior art, Figure 2 is a front view showing a spray box in the mechanical polishing apparatus according to the prior art.

1 and 2, the first transfer means 52 pulls out the semiconductor wafer 7 waiting in the load cassette 51 in the wafer cassette 8 and waits for the wafer in a work ready state. It will be stored in the spray box 60 to be. The semiconductor wafer 7 housed in the spray box 60 is transferred to the polishing head portion 55 having the plurality of polishing heads 56, 57, 58, and 59 by the second transfer means 54. The semiconductor wafer 7 whose surface treatment is completed in the polishing head part 55 is again transferred to the spray box 60 by a 2nd transfer means. Usually, the spray box 60 has a mounting base 61 for accommodating a plurality of semiconductor wafers 7, and before the spray box 60 is transferred to the next position (for example, a cleaning device) from the mounting base 61, Ultrapure water is injected through the spray nozzle 63 so that the slurry on the surface of (7) does not dry out. Next, it is transferred to the cleaning apparatus not shown in the figure by the first transfer means, and the cleaning operation is carried out, and then stored in the wafer cassette 8.

In the conventional chemical mechanical polishing apparatus, since the first transfer means and the second transfer means are installed to move only by a specified value, if the semiconductor wafer has any external force or a state defect of the first and second transfer means. If the semiconductor wafer is placed in the wrong position due to various factors, the semiconductor wafers from later on are displaced in all unit devices. Once the position of the semiconductor wafer is misplaced, it may cause damage to the semiconductor wafer or the unit device in the unit device after the next operation rather than the wrong unit device. This problem is often caused by misplaced semiconductor wafers in spray boxes.

SUMMARY OF THE INVENTION An object of the present invention is to provide a chemical mechanical polishing apparatus capable of correcting misalignment during transport of a semiconductor wafer so as to prevent damage to the semiconductor wafer or equipment damage due to misalignment of the semiconductor wafer. .

1 is a schematic configuration diagram of a chemical mechanical polishing apparatus according to the prior art,

Figure 2 is a front view showing a spray box in a mechanical polishing apparatus according to the prior art,

3 is a schematic configuration diagram of a chemical mechanical polishing apparatus according to the present invention;

4 is a front view showing a spray box in the chemical mechanical polishing apparatus according to the present invention,

5 is a perspective view showing a wafer aligner in another embodiment of the chemical mechanical polishing apparatus according to the present invention.

Explanation of symbols on the main parts of the drawings

7; Semiconductor wafer 8; Wafer cassette

10,50; Chemical mechanical polishing apparatus 11,51; Load station

12,52; First transport means 14,54; Second transport means

16,56,57,58,59; Abrasive head portion 20,60; Spray box

21,61; Mounting table 22,62; Detection sensor

23,63; Spray nozzle 24; Roller bar

31; Upper head 32; Bottom head

33; Abrasive cloth 34; Slurry

40; Wafer aligner 41,42; Payload

43; Alignment pin

The chemical mechanical polishing apparatus according to the present invention for achieving the above object is a load station on which a cassette containing a plurality of semiconductor wafers needing planarization is mounted, a solution for preventing drying so that the semiconductor wafer is stored and the semiconductor wafer is not dried. A spray box having a means for spraying a surface, a polishing head portion for polishing the surface of the semiconductor wafer by a slurry and being subjected to mechanical friction, a first transfer means for transferring the semiconductor wafer between a load station and the spray box, and a spray box And a second transfer means for transferring the semiconductor wafer between the polishing head portions, wherein the chemical mechanical polishing apparatus further comprises alignment means for aligning the semiconductor wafer so as to be precisely positioned at an operating position of the first and second transfer means. It is done.

Hereinafter, a chemical mechanical polishing apparatus according to the present invention will be described in detail with reference to the accompanying drawings.

Figure 3 is a schematic configuration diagram of a chemical mechanical polishing apparatus according to the present invention, Figure 4 is a front view showing a spray box in the chemical mechanical polishing apparatus according to the present invention.

3 and 4, the chemical mechanical polishing apparatus 10 according to the present invention includes a load station 11, a first transfer means 12, a spray box 20, a second transfer means 14, a plurality of The polishing head part which has the polishing head 16 of this is provided.

The load station 11 is equipped with a plurality of wafer cassettes 8 for accommodating a plurality of semiconductor wafers 7 requiring planarization processing or a semiconductor wafer 7 for which planarization processing is completed. The load station 11 performs vertical movement for storing or transferring the semiconductor wafer 7.

The spray box 20 is for temporarily waiting before and after surface treatment of the semiconductor wafer 7, and a plurality of mounting tables 21 facing each other are arranged vertically so that the semiconductor wafer 7 can be placed. A detection sensor 23 is installed at the distal end of the mount 21 to detect the presence or absence of the semiconductor wafer 7, and a spray nozzle 23 for spraying ultrapure water like a water fog between the mounts 21 in the vertical direction. ) Is installed. The front of the mounting table 21 is provided with a roller bar 24 extending in the vertical direction for the alignment of the semiconductor wafer 7. This roller bar 24 is provided so as to move left and right in front of the spray box 20.

The polishing head portion is used to planarize the semiconductor wafer 7 and is made of a plurality of polishing heads, but only one polishing head 16 is shown in the drawing. The polishing head 16 has an upper head 31 which adsorbs the semiconductor wafer 7 and a lower head 32 to which the polishing cloth 33 is attached.

First transfer means 12 which adsorbs the semiconductor wafer 7 between the load station 11 and the spray box 20 to take out the semiconductor wafer 7 from the wafer cassette 8 or to receive it in the wafer cassette 8. Is installed. Then, between the spray box 20 and the polishing head 16, the semiconductor wafer 7 is adsorbed and transferred from the spray box 20 to the polishing head 16 or from the polishing head 16 to the spray box 20. The second transfer means 14 is provided.

Referring to the operation, first, a wafer cassette 8 in which a plurality of semiconductor wafers 7 requiring planarization processing is accommodated is mounted in the load station 11. The load station 11 lowers the wafer cassette 8 so that the semiconductor wafer 7 can be positioned at the operating position of the first transfer means 12. The first transfer means 12 absorbs the semiconductor wafer 7 located at the bottom of the wafer cassette 8 so that the edge portion of the semiconductor wafer 7 is placed on the mounting table 21 of the spray box 20 in order. To receive it. The spray box 20 usually has a number of mounts 21 to accommodate five. When the accommodated semiconductor wafer 7 is placed on the mounting table 21 of the spray box 20, the roller bar 24 moves from side to side on the front surface of the semiconductor wafer 7 to position the semiconductor wafer 7. Align it. Here, the semiconductor wafer 7 is a flat zone type in which one edge portion thereof is cut off and the flat surface 9 is formed, and the roller bar 24 is left and right on the flat surface 9 of the semiconductor wafer 7. Move to the original position by pushing the protruding part. The roller bars 24 are formed vertically so that the plurality of semiconductor wafers 7 can be aligned at once.

The second wafer transfer means 14 is sucked by the second transfer means 14 and transferred to the polishing head 16. The semiconductor wafer 7 is caused by mechanical friction on the polishing cloth 33 attached to the lower head 32 which is rotating in the state in which the upper head 16 which rotates the transferred semiconductor wafer 7 is fixed by suction. The surface is polished. At this time, the slurry 34 is supplied from the top of the polishing cloth 33. The surface of the semiconductor wafer 7 is planarized by chemical reaction with the slurry 34 and mechanical friction with the polishing cloth 33.

The polished semiconductor wafer 7 is transferred to the spray box 20 by the second transfer means 14 again. The transferred semiconductor wafer 7 sprays ultrapure water through the spray nozzle 23 so that the slurry 34 deposited on the surface of the semiconductor wafer 7 in the spray box 20 does not harden before cleaning. This prevents the occurrence of the slurry 34 that hardens and is not cleaned. The semiconductor wafer 7 accommodated in the spray box 20 is detected by the detection sensor 22. Positioning with respect to the semiconductor wafer 7 may be effected once more by the movement of the roller bar 24 in this spray box 20.

The first transfer means 12 transfers the semiconductor wafer 7 to the unit device for cleaning, although not described in the drawings housed in the spray box 20, and transfers the cleaned semiconductor wafer 7 to an empty wafer cassette ( 8).

Such a chemical mechanical polishing apparatus corrects the positional shift of the semiconductor wafer due to a malfunction of the first and second transfer means, malfunction of each unit, and external factors between the load station, the spray box, the spray box, and the polishing head portion. do.

The present invention has been described that the roller bar is provided as a position alignment means in the spray box is not limited to this and various modifications are possible within the scope without departing from the technical spirit of the present invention. For example, the following wafer aligner can be separately installed in the chemical mechanical polishing apparatus as the position alignment means of the semiconductor wafer.

5 is a perspective view showing a wafer aligner in another embodiment of the chemical mechanical polishing apparatus according to the present invention.

Referring to FIG. 5, the wafer aligner 40 is provided with two mounting plates 41 and 42 so as to be spaced apart by a predetermined distance which is operated to move away from or close to each other. A plurality of alignment pins 43 are formed on the two mounting plates 41 and 42 so as to correspond to the curvature of the semiconductor wafer 7, respectively.

When the semiconductor wafer 7 is mounted while the mounting plates 41 and 42 are separated from each other, each of the mounting plates 41 and 42 moves toward the center and the position where the semiconductor wafer 7 is determined by the alignment pin 43. Until it is correctly aligned with. This wafer aligner 40 may be installed between each unit device constituting the chemical mechanical polishing apparatus.

According to the chemical mechanical polishing apparatus according to the present invention as described above, the chemical mechanical polishing operation can be performed smoothly by correcting the positional displacement of the semiconductor wafer that can be generated in the equipment to prevent the occurrence of equipment damage or semiconductor wafer damage have. In particular, when the position alignment means is provided in the spray box in which the positional shift of the semiconductor wafer occurs frequently, the effect can be enhanced.

Claims (5)

A load station on which a wafer cassette containing a plurality of semiconductor wafers requiring planarization is mounted; A spray box having means for injecting ultrapure water for preventing drying so that the semiconductor wafer is accommodated and the semiconductor wafer is not dried; Polishing head portion for polishing the surface of the semiconductor wafer by a mechanical friction while receiving a slurry; First transfer means for transferring the semiconductor wafer between the load station and the spray box; And A chemical mechanical polishing apparatus comprising: a second transfer means for transferring the semiconductor wafer between the spray box and the polishing head portion, And an alignment means for aligning the semiconductor wafer so as to be accurately positioned at an operating position of the first and second transfer means. The chemical mechanical polishing apparatus according to claim 1, wherein the alignment means aligns the semiconductor wafer installed in the spray box. The method of claim 2, wherein the spray box is formed with a plurality of slots facing each other to accommodate the plurality of the semiconductor wafer, the alignment means is in contact with the side of the plurality of semiconductor wafers stored therein aligned Chemical mechanical polishing apparatus, characterized in that the roller bar. 4. The chemical mechanical polishing apparatus according to claim 3, wherein the semiconductor wafer has a shape in which a part of an edge thereof is cut off and a side surface thereof is flat, and the roller bars are aligned in contact with the flat surface. The semiconductor device of claim 1, wherein the alignment means includes a plurality of fins formed in contact with a side surface of the semiconductor wafer, and includes a plurality of mounting plates on which the semiconductor wafer is placed. And move toward the center to align the semiconductor wafer.