JPS5914469A - Polishing apparatus - Google Patents

Abstract

PURPOSE:To improve finishing speed and accuracy in a polishing apparatus for finishing a mirror surface by attaching a plurality of polishing pads with different hardness and surface roughness to a surface plate. CONSTITUTION:On a surface plate 1 mounted on a rotary table 10 are laid concentrically polishing pads 11-13 with rough, medium and fine roughness in the order arranged from the outer periphery. On the other hand, a work O such as silicon wafer is mounted by adsorption, adhesion, etc. on a work holder 2 supported rotatably and swingably by a ball joint 3 and lowered onto the rotating surface plate. And a work 21 lowered first onto the pad 1 rotates with the peripheral difference to be flattened efficiently. Next, a work 22 lowered onto the pad 12 is subjected to the secondary finish and a work 23 finally lowered onto the pad 13 is subjected to mirror finish with fine surface roughness and small peripheral speed. Thus, the finishing speed and accuracy can be improved and the number of manual operation is reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a polishing device, particularly in one step.
The present invention relates to a high-performance polishing device that completes l-'+7 tweezing work.

A polishing device is a device that places abrasive grains or polishing pads on a surface plate on a rotary table, attaches a workpiece to a rotatably supported workpiece holder, places the lid on the rotary table, and polishes the workpiece to give it a mirror finish. It is.

The process of finishing lapped and etched workpieces to a mirror finish involves firstly increasing the polishing amount to flatten the surface of the workpiece, and secondly improving the surface finish to reduce roughness and minute scratches on the workpiece surface. It is easier to understand if you consider it separately from the process. The main purpose of the first flattening process is to remove deep scratches on the surface of the cut workpiece, so the first planarization step is to remove deep scratches from the surface of the cut workpiece. '? Jahl] It is important to increase the pressure and polishing amount quickly.The 20th surface finishing process smoothes the surface of the workpiece, which is flat as a whole but has a large surface roughness, to a fine surface roughness. In the process of converting, listening is not required.

Conventionally, the flattening process was first performed on a rotary table with a uniform pad spread over the entire surface, and then the finer I\
°A separate polishing device or surface plate with a lid was used to perform the process of refining the surface roughness. By the way, the peripheral speed of the surface plate surface is high at the outer periphery and decreases as it approaches the inner periphery.

Therefore, the outer periphery is suitable for the planarizing process, but not for the surface finishing process, and on the contrary, the inner periphery is not efficient for the planarizing process. However, it has been impossible to utilize this point with conventional polishing equipment that has uniform particle size over the entire surface.

In view of the above points, the present invention aims to improve the efficiency of the process, improve the quality of the finished surface, and reduce the number of operations.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a plan view of a main part of an embodiment of the invention, and FIG. 2 is a side view of the same. Referring to both figures, the surface plate (1) has a concentric circular threading pad (13) on the top surface of the rotary table (10).
). Work holder (2)
The rotatable swing valve is freely supported by a pole joint (3) or the like, and is moved by an arm (5) that rotates a column (4).

7-ri (01 is, for example, a silicon wafer made of a semiconductor chip material, etc.) is attached to a work holder (2) by adsorption or adhesion, and both work holders (21) are lowered onto a surface plate to begin the polishing process.

In the poly 1.7 polishing process, the first process of rough finishing of planarization is to polish the workpiece (21) with a rough polishing pad (11).
The workpiece is lowered to a position within the range of , and the workpiece rotates on its own axis depending on the circumferential speed of the surface plate.

At this time, the polishing pad (11) has a rough surface and a large area, so the "sharpness" of the abrasive grains is maintained for a long time, and the circumferential speed is also high, so that the planarization process proceeds efficiently. After the planarization process is completed, or by cleaning the polishing particles, the area of the medium-grained polishing pad (12) (
At step 22), the workpiece is unloaded and enters a secondary process in which the rough finished surface produced in the primary flattening process is made thin. In the same way, the workpiece is finished by entering the tertiary mirror finishing process. The area of the polishing pad (13) on the inner circumference (Z3
) Since the polishing of the K workpiece is carried out at a small circumferential speed and with a large amount of microorganisms, only a small amount of polishing is required, and it is suitable for the tertiary process where the finished surface needs to be roughened or finely polished. It is suitable. The secondary process is 1
Since it has an intermediate character between the next step and the tertiary step, it is also suitable that it is in the middle range (22).

As a result of the above, the polishing efficiency and the quality of the finished surface are satisfactory, and the entire process can be completed while the workpiece remains attached to the workpiece holder, which also saves operating time.

Note that when attaching and removing a workpiece, problems such as chipping or bending of the workpiece, and whether or not the workpiece is installed in the correct position on the workpiece holder are likely to occur when automated, but with this invention, the entire process can be done without leaving the workpiece attached. , it is suitable for automation, and greatly contributes to labor saving.

In the above embodiments, polishing pads (11) (12,
) (13), but (11) (12)
Similar effects can also be achieved by providing a partition between (13) and flowing abrasive grains into the partition.

In this case, it is essential to wash the abrasive grains between the primary, secondary, and tertiary processes, but it is possible to immerse the workpiece holder with the workpiece attached in the cleaning solution, so the impact on labor saving is small. stomach.

Furthermore, although the embodiments have been exemplified by three steps of roughing, medium and finishing, it goes without saying that two or four or more steps are also possible.

Since this invention is a polishing device in which a plurality of boring pads with different pupils are attached to a single surface plate, the optimum surface compensation and speed can be selected for the polishing process. Since the polishing process can be performed with the workpiece still attached, the finishing speed of the polishing process is improved, the finishing accuracy is good, and the number of operations can be reduced, making it possible to obtain an elegant device.

[Brief explanation of the drawing]

FIG. 1 is a plan view of one embodiment of the present invention, and FIG. 2 is a side view of the same. 1... Surface plate 2... Work holder 3... Ball joint 4... Support column 5... Arm 10...
rotary table

Claims (1)

[Claims] and υ゛Miscellaneous ■ A polishing device characterized in that a plurality of polishing pads of different hardness are attached to a single surface plate.