KR100591011B1 - Method of fixing the arm of chemical mechanical polishing device - Google Patents

Abstract

The present invention relates to a method of fixing an arm in a CMP process by inserting a fixing device in one lower portion of an arm connecting the head of the CMP device and the CMP body.

The arm fixing method of the chemical mechanical polishing apparatus of the present invention has a technical feature in that the fixing means is inserted into one lower portion of the arm connecting the head and the main body to prevent the wafer from slipping in the arm during the planarization process.

Therefore, the arm fixing method of the chemical mechanical polishing apparatus of the present invention does not have a wafer slip phenomenon due to the reaction force of the membrane pressure, and due to the arm down force and the retaining ring pressure, the carrier base and the arm shaft assembly are generated due to a large load. Frequent problems with the carrier base can be solved, and the retaining ring life due to the simultaneous loading of the arm down force and retaining ring pressure can extend the short life time of 1000 wafers, and the arm down force and retaining ring Due to the pressure repulsion action, it is possible to suppress the phenomenon in which the nonuniformity caused by the membrane hunting is momentarily increased, thereby improving productivity, cost reduction, and equipment utilization rate.

Arm, fixture

Description

Method for fixing arm of chemical mechanical polish equipment             

1 is a photograph of a head of a CMP apparatus according to the present invention.

2 is a cross-sectional view showing the pressure generated in the polishing head portion of the CMP apparatus according to the present invention.

3 is a perspective view of an embodiment according to the present invention.

Figure 4 is a photograph showing an area to be inserted into the fixing device of the lower side of one arm.

Generally, integrated circuits are formed by sequential deposition of conductor layers, semiconductor layers, or insulating layers on a substrate, in particular a silicon wafer. After deposition of each layer, it is etched to form a circuit configuration. After a series of layers are sequentially deposited and etched, the outer or top side of the substrate, i.e. the exposed surface of the substrate, is gradually unplanarized. This unplanarized surface presents a problem in the photolithography step of the integrated circuit fabrication process. Therefore, it is necessary to periodically planarize the substrate surface.

Chemical Mechanical Polish (CMP) is one of the methods of planarization. Typically, this CMP method requires mounting a substrate on a carrier or polishing head. The exposed surface of the substrate is disposed towards the rotating polishing pad. The polishing pad may be a general or pad to which an abrasive is fixed. Standard polishing pads have a durable rough surface, while pads having fixed abrasives have abrasive particles held in the receiving medium. The carrier head provides a controllable rod, ie pressure, on the substrate for pushing the polishing pad. When using a conventional pad, a polishing slurry containing at least one chemical reaction agent and abrasive particles is supplied to the surface of the polishing pad.

The efficiency of the CMP process can also be measured by the polishing rate of the substrate surface, the finished state of the resultant (small surface irregularities) and the planarization (the absence of large topography). Polishing rate, finish and planarization are determined by the bond between the pad and the slurry, the relative speed between the substrate and the pad, and the force applying the substrate to the pad.

There are two types of grinding heads: the plant type uses arm down force and n2 back pressure during polishing, and the membrane type uses down arm during polishing. Arm down force, membrane pressure, retain ring pressure are used.

In the membrane type, due to the structural problem of the arm, if there is no arm down force, wafer slip occurs during polishing. Arm down force must be used continuously to prevent wafer slip. However, due to the use of the arm down force, the additional load of the retaining ring pressure and the membrane pressure acts, which leads to the fatal problems of pressure hunting and deterioration of the life of the retaining ring.

Therefore, the present invention is to solve the problems of the prior art as described above, by fixing the fixing device on the lower side of the arm so that the arm does not shake even without operating the stabilizer (stabilizer), because there is no shaking of the membrane It is an object of the present invention to provide a method for avoiding wafer slip due to pressure reaction.

The object of the present invention is to chemically mechanically insert a fixing device under one side of the stabilizer block of the arm connecting the head and the main body of the chemical mechanical polishing apparatus to prevent the wafer from slipping in the arm during the planarization process It is achieved by the arm fixing method of the polishing apparatus.

In addition, the object of the present invention comprises a fixing device inserted below one side of the stabilizer block of the arm connecting the head and the main body of the chemical mechanical polishing apparatus to prevent the wafer from slipping in the arm during the planarization process. It is also achieved by a chemical mechanical polishing apparatus.

In the existing plant type, a stabilization device is used to prevent arm shaking when the arm moves. Since the arm down force is input during polishing, there is no rocking of the arm even when the stabilization device is not operated. However, in the membrane type, the membrane pressure and the retaining ring pressure are sufficient to process, but without the arm down force, the wafer slips due to the rocking of the arm during polishing. In order not to use the existing arm down force, it is necessary to fix the arm.

There are various methods of fixing, but in the present invention, the arm is not shaken by inserting and fixing the fixing device at one lower side of the arm. Since there is no rocking of the arm, there is no wafer slip due to the reaction force of the membrane pressure. Due to the arm down force and the retaining ring pressure, the carrier base and the arm shaft assembly can be heavily loaded to solve the problems in the carrier base. The short life of the retained ring wafer by 1000 can be extended due to the load, and the non-uniformity caused by membrane pressure hunting due to the reaction of the arm down force and the retaining ring pressure. This momentary increase can be curbed, improving fab yield, cost savings and equipment utilization.

Details of the above object and technical configuration of the present invention and the effects thereof according to the present invention will be more clearly understood by the following detailed description with reference to the drawings showing preferred embodiments of the present invention.

<Example>

AVANTI 472 SYSTEM is one of the systems applied to the CMP technology. The configuration is composed of a load / unload station, a polish arm head station, a plate station, a high / low voltage station and the like.

First, Figure 1 is a photograph showing the polishing head portion of the CMP apparatus. The wafer is mounted on the polishing head and then the desired planarization operation is performed to proceed with the process.

Next, FIG. 2 is a cross-sectional view showing the pressure generated in the polishing head portion of FIG. The wafer 2 is rotated around the polishing axis 1 to planarize the wafer, and an arm down force 4 is applied to prevent the wafer from slipping, and the retaining ring pressure in the retaining ring 5 is applied. The membrane pressure 8 is generated in the membrane 6 and the membrane 7 to fix the wafer.

The above method is a phenomenon that occurs when the stabilization device located on one side of the arm is operated, that is, when the arm down force is injected. As described above, the life of the retaining ring is short. It shows that the wafer cannot be polished normally without using the arm down force 4. However, the present invention not only prolongs the life of the retaining ring but also provides an apparatus for normally polishing a wafer without using an arm down force.

3 is a perspective view of the Avanti 472 system. As shown in Fig. 3, the Avanti 472 system is configured, and the circled area is the stabilization device 9 described in the present invention.

Next, Figure 4 is an enlarged photo of the stabilization device of Figure 3, by inserting a block space that can be used as a fixing device of the arm to the stabilization block block 10 to prevent the arm from shaking even without operating the stabilizer. have. In this case, the block space needs only to have a height of 0.6 to 0.8 cm (preferably 0.7 cm). That is, any shape, length, and material may be used. FIG. 5 is a partial cross-sectional view of the enlarged photograph of FIG. 4, showing an example in which a block space is inserted.

It will be apparent that changes and modifications incorporating features of the invention will be readily apparent to those skilled in the art by the invention described in detail. It is intended that the scope of such modifications of the invention be within the scope of those of ordinary skill in the art including the features of the invention, and such modifications are considered to be within the scope of the claims of the invention.

Therefore, the arm fixing method of the chemical mechanical polishing apparatus of the present invention has no wafer slip phenomenon caused by the reaction force of the membrane pressure by inserting the fixing device under one side of the arm, and the carrier base and the arm due to the arm down force and the retaining ring pressure. By applying a lot of load to the shaft assembly, it is possible to solve the problems in the carrier base, and to extend the short life of about 1000 sheets of the retaining ring wafer due to the simultaneous load of the arm down force and the retaining ring pressure, Due to the repulsive action of the force and the retaining ring pressure, it is possible to suppress a phenomenon in which the nonuniformity generated by the membrane hunting is momentarily increased, thereby improving productivity, cost reduction, and equipment utilization rate.

Claims (6)

In the method of fixing the arm of a chemical mechanical polishing device, In order to prevent the wafer from slipping in the arm during the planarization process, the arm fixing method of the chemical mechanical polishing apparatus, characterized in that the fixing device is inserted into the lower side of one side of the stabilizer block of the arm connecting the body and the main body of the chemical mechanical polishing apparatus. . The method of claim 1, And the fixing device is used when performing a flattening process without injecting an arm down force in a membrane mechanical type chemical mechanical polishing device. In the chemical mechanical polishing apparatus, And a fixing device inserted below one side of the stabilizer block of the arm connecting the head and the main body of the chemical mechanical polishing apparatus to prevent the wafer from slipping on the arm during the planarization process. The method of claim 3, wherein And the fixing device uses block space. The method of claim 4, wherein The block space is a chemical mechanical polishing apparatus, characterized in that the height is 0.6 to 0.8cm. The method of claim 3, wherein And the fixing device is attached to the arm of the membrane type device in place of the stabilizing device.

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