KR20040054055A - Sputtering apparatus for manufacturing semiconductor devices - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for manufacturing a semiconductor device, wherein the apparatus is installed in a process chamber, an electrostatic chuck installed in the process chamber, on which a semiconductor substrate is placed, and a material used for processing the semiconductor substrate is deposited on the electrostatic chuck. And a deposition ring positioned to surround the electrostatic chuck to prevent it. The inner portion is formed to have a width of 1.6mm to 2.0mm, it is possible to increase the reuse number of the expensive deposition ring compared to the general case.

Description

Sputtering equipment for semiconductor device manufacturing {SPUTTERING APPARATUS FOR MANUFACTURING SEMICONDUCTOR DEVICES}

The present invention relates to an apparatus for manufacturing a semiconductor device, and more particularly to a sputtering facility with an increased number of reuse of deposition rings used for side protection of an electrostatic chuck.

Processing techniques for film formation on a wafer in a semiconductor manufacturing process can be roughly divided into physical vapor deposition (chemical vapor deposition) and chemical vapor deposition (chemical vapor deposition). Among them, physical vapor deposition is a processing technology in which a particle having a high energy is collided with a target formed of a target material to be laminated, and the target material is separated from the target to stack the target material on a substrate. Sputtering, which has an advantage of easy and excellent step coverage, is mainly used.

In general, the equipment for which sputtering is performed is composed of a process chamber, a target portion positioned in the upper portion of the process chamber, and a substrate portion positioned in the process chamber so as to face the target portion vertically. The substrate portion is provided with an electrostatic chuck that sucks the wafer in a vacuum, and a deposition ring is installed around the electrostatic chuck to prevent particles to be deposited on the wafer during wafer processing from being deposited on the electrostatic chuck. The deposition ring is made of titanium (Ti) and beaded and etched for regeneration after a certain period of time. However, as the number of regeneration increases, the height of the side portion of the upper limb deposition ring protecting the side of the electrostatic chuck is lowered. When the height is lower than the height determined by the management standard, the particles are deposited on the side of the electrostatic chuck. As a result, the inner side of the deposition ring and the side surface of the electrostatic chuck are attached so that the deposition ring is not separated from the electrostatic chuck. Therefore, when the side portion of the deposition ring is lowered for each height determined by the management criteria, the expensive deposition ring is discarded.

In general, the deposition ring has an inner side facing the side of the electrostatic chuck having a width of about 1 mm, and after being beaded and etched about six times and reused, the inner side becomes low enough to cause the above-mentioned problems. do.

In order to solve the above-mentioned problem, an object of the present invention is to provide a sputtering apparatus including a deposition ring that can increase the number of times of regeneration and use.

1 is a schematic cross-sectional view of a sputtering apparatus according to a preferred embodiment of the present invention;

FIG. 2 is an enlarged view of a portion 'A' of FIG. 1 enlarged; and

3A and 3B are diagrams showing whether the predetermined particles are deposited on the electrostatic chuck when using the general deposition ring and the deposition ring of the present invention, respectively.

Explanation of symbols on the main parts of the drawings

100: process chamber 200: target portion

300: substrate portion 320: electrostatic chuck

340: evaporation ring 344: inner part

346: stopper part

In order to achieve the above object, the sputtering apparatus of the present invention is provided with a process chamber, an electrostatic chuck installed in the process chamber, on which a semiconductor substrate is placed, and a material used to process the semiconductor substrate to prevent deposition on the electrostatic chuck. And a deposition ring positioned to surround the electrostatic chuck. The deposition ring has a height equal to or lower than that of the electrostatic chuck, and protrudes to a position higher than the electrostatic chuck to prevent the semiconductor substrate placed on the inner side and the electrostatic chuck positioned to face the side of the electrostatic chuck from sliding over a predetermined distance. It is provided with a stopper part. The inner portion has a width wider than 1.0 mm and is located inward of the semiconductor substrate positioned on the top of the electrostatic chuck. Preferably the inner portion is formed to have a width of 1.6mm to 2.0mm.

According to the sputtering apparatus of the present invention having the above-described characteristics, it is possible to increase the number of reuse of expensive deposition rings as compared with the general case.

Hereinafter, an embodiment of the present invention will be described in more detail with reference to FIGS. 1 and 3. In the drawings, the same reference numerals are given to components that perform the same function.

The embodiments of the present invention may be modified in various forms, and the scope of the present invention should not be construed as being limited by the embodiments described below. This embodiment is provided to more completely explain the present invention to those skilled in the art. Therefore, the shape of the elements in the drawings are exaggerated to emphasize a clearer description. In the following embodiment, a sputtering apparatus for depositing aluminum on a wafer will be described as an example. However, the technical idea of the present invention is also applicable to the deposition of other materials such as titanium (Ti) or titanium nitride (TiN).

1 is a schematic diagram of a sputtering apparatus according to a preferred embodiment of the present invention. Referring to FIG. 1, the sputtering facility includes a process chamber 100, a target part 200, and a substrate part 300.

The process chamber 100 is a chamber in which a sputtering process is performed and is maintained in a vacuum state for smooth process progression. The target part 200 is a part for supporting a material to be deposited on a semiconductor substrate such as a wafer W, and a backing plate (not shown) for fixing and supporting the target in addition to the target and the target part. And a cooling system (not shown) for cooling. The substrate unit 300 has a circumference of the electrostatic chuck 320 to prevent aluminum particles from being deposited on the electrostatic chuck 320 on which the wafer is placed and the side surface 321 of the electrostatic chuck 320. It is provided with a deposition ring (340) made of sus (SUS) or titanium (Ti) material surrounding the. Unexplained reference numerals 322, 324, 326, and 328 denote electrodes, heaters, bellows, and gas tubes, respectively, and thus are departed from the gist of the present invention. Omit.

FIG. 2 is an enlarged view of portion 'A' of FIG. 1 to show a deposition ring. 2, the deposition ring 340 includes a base part 342, an inner part 344, a stopper part 346, and an outer side part 348. ) The base portion 342 is a portion constituting the lower portion of the deposition ring 340, the inner portion 344 is a portion facing the side 311 of the electrostatic chuck 320. A minute space exists between the side surface 311 of the electrostatic chuck 320 and the inner portion 344 of the deposition ring 340. The stopper part 346 is for preventing the wafer from slipping due to chucking errors or the like when the wafer is placed on the electrostatic chuck 320. The stopper part 346 protrudes to a position higher than the wafer placed on the electrostatic chuck 320 and is formed to surround the wafer at a position spaced apart from the wafer by a predetermined distance.

The inner part 344 protrudes upward from the base 342, and the protruding height preferably has the same height as the electrostatic chuck 320. When the inner portion 344 protrudes to a position higher than the electrostatic chuck 320, a wafer cannot be stably placed on the electrostatic chuck 320, and the gas pipe 328 may maintain the uniform temperature. ), The gas supplied to the backside of the wafer is leaked out. On the contrary, when the inner part 344 has a height lower than that of the electrostatic chuck 320, aluminum is deposited on the upper edge and side surfaces 321 of the electrostatic chuck 320. As a result, the wafer is not stably placed on the electrostatic chuck 320, and the side surface 321 of the electrostatic chuck 320 and the deposition ring 340 are attached to each other so that the wafer is not separated later. Leakage current is generated in the deposited portion. Since it is impossible to form the inner portion 344 of the deposition ring 340 to have exactly the same height as the electrostatic chuck 320, the height of the inner portion 344 is smaller than the electrostatic chuck 340. mm) is formed to be low.

In general, the deposition ring 340 is reused after performing a bead and etching treatment after a predetermined period of use, and the height of the inner portion is reduced by about 0.044 mm every three times. Therefore, as the number of regeneration increases, the inner portion 344 of the deposition ring 340 becomes lower than the electrostatic chuck 320 so that the above-mentioned problem occurs, and thus, the predetermined number (about six times) or more. After reuse, the deposition ring 340 should be discarded.

One of the main features of the present invention is that the width of the inner portion 344 of the deposition ring 340 is wider than usual in order to increase the number of reuse of the deposition ring 340.

3A and 3B are diagrams for explaining deposition of aluminum particles on the electrostatic chuck according to the width of the inner portion of the deposition ring. FIG. 3A shows a typical deposition ring whose width is approximately 1 mm, and FIG. 3B shows the deposition ring in the present invention improved to increase the width to 1.6 mm. Arrows in the figure show the direction of movement of the aluminum particles.

3A and 3B, aluminum particles collide with the base 342 and are reflected toward the inner portion 344 during the process. However, the deposition of aluminum particles on the electrostatic chuck 320 depends on the width of the inner portion 344 of the deposition ring 340 having the same height. That is, as shown in FIG. 3A, aluminum particles are deposited when the general deposition ring 340 having a width of 1 mm is used. However, as shown in FIG. 3B, the deposition ring 340 having the width of the inner part 344 increased to 1.6 mm. When used, aluminum particles hit at the same angle and at the same point of the base 342 are not deposited on the electrostatic chuck 320. Therefore, the deposition ring 340 having an increased width of the inner portion 344 may be used even if the height of the inner portion 344 is lower than that of the general deposition ring, and as a result, the number of reuse of the deposition ring 340 is increased. do.

The width of the inner portion 344 of the deposition ring 340 should be located inside the side portion of the wafer placed on the electrostatic chuck. This is because when the inner portion 344 of the deposition ring 340 is exposed out of the wafer, aluminum is deposited on the inner portion 344 of the deposition ring 340, thereby attaching the wafer to the deposition ring 340. This can happen. In general, since the edge of the wafer is about 3mm away from the electrostatic chuck 320, the inner portion 342 of the deposition ring 340 preferably has a width of 1.6mm to 2mm.

According to the sputtering apparatus of the present invention, it is possible to increase the number of reuse of expensive deposition rings as compared with the general case, thereby reducing the cost.

Claims (4)

In the sputtering apparatus for manufacturing a semiconductor element, A process chamber; An electrostatic chuck installed in said process chamber and on which a semiconductor substrate is placed; A deposition ring positioned to surround the electrostatic chuck to prevent the material used in processing the semiconductor substrate from being deposited on the electrostatic chuck; And the deposition ring has an inner portion having a height equal to or lower than the electrostatic chuck and positioned to face the side of the electrostatic chuck and having a width greater than 1.0 mm. The method of claim 1, And the inner portion of the deposition ring is located inward of the semiconductor substrate placed on the electrostatic chuck. The method of claim 2, And the deposition ring further comprises a stopper portion protruding to a position higher than the electrostatic chuck to prevent the semiconductor substrate placed on the electrostatic chuck from sliding over a predetermined distance. The method of claim 1, Sputtering apparatus, characterized in that the inner portion of the deposition ring has a width of 1.6mm to 2.0mm.