KR20030023267A - Electrostatic chuck for use in semiconductor fabricating equipment - Google Patents

Abstract

PURPOSE: An electrostatic chuck of semiconductor fabrication equipment is provided to exchange only a chucking plate in an exchanging process of the electrostatic chuck by improving a structure of the electrostatic chuck. CONSTITUTION: The RF power is applied to a bottom electrode(100). An electrostatic chuck body(120) is fixed to the bottom electrode(100). A positive pole electrode bar(122) and a negative pole electrode bar(124) are formed at the electrostatic chuck body(120). A chucking plate(160) has a structure which is coupled with the electrostatic chuck body(120) or decoupled from the electrostatic chuck body(120). An electrostatic chuck is formed with the electrostatic chuck body(120) and a chucking plate(140). The chucking plate(140) is connected with the electrostatic chuck body(120). A coolant flow line is formed at the electrostatic chuck body(120).

Description

ELECTRICAL CHUCK FOR USE IN SEMICONDUCTOR FABRICATING EQUIPMENT

The present invention relates to a semiconductor manufacturing apparatus, and more particularly to an electrostatic chuck that chucks a wafer as a workpiece.

In the semiconductor manufacturing process, chucks are used to support or hold the semiconductor substrate in order to prevent the semiconductor substrate from moving or misaligning during the process. Electrostatic chucks that use electrostatic attraction forces to hold a semiconductor substrate have some advantages over other types of chucks (eg, mechanical chucks and vacuum chucks). As one of those advantages, electrostatic chucks can reduce stress-related cracks often caused by mechanical clamps.

Such electrostatic chucks are entitled "ELECTROSTATIC CHUCK". Patent No. 4,665,463, entitled "METHOD OF AND APPARATUS FOR APPLYING VOLTAGE TO ELECTROSTATIC CHUCK". Patent No. 5,117,121 and entitled "ELECTROSTATIC CHUCK HAVING A THERMAL TRANSFER REGULATED PAD." Patent No. 5,978,202, respectively, incorporated by reference.

In general, an electrostatic chuck includes a pair of electrodes embedded in a chuck body or sheet of dielectric material. A workpiece, such as a silicon wafer, is placed on the electrostatic chuck. When a voltage is applied between the electrodes, the electrostatic chuck electrostatically attracts the silicon wafer in accordance with the Johnson-Rahbek effect.

1 is a view showing an electrostatic chuck of a semiconductor manufacturing facility according to the prior art, Figure 2 is a cross-sectional view showing a cross-sectional structure of the electrostatic chuck according to the prior art.

As shown in the figure, the electrostatic chuck according to the prior art is assembled to the lower electrode so as to be directly connected to the positive and negative electrodes at the lower electrode. A chucking voltage is applied while the positive electrode and the negative electrode of the electrostatic chuck are insulated. Since the positive electrode and the negative electrode are insulated from one body, the electrostatic chuck itself is inseparable from each component and fails when the insulation breaks. For this reason, when the electrostatic chuck needs to be replaced due to the damage caused by RF power or the chucking ability decreases, the chuck itself must be replaced since the entire electrostatic chuck forms a positive and negative electrode. .

When fabricating an electrostatic chuck that chucks the wafer, the particles on the back side of the wafer during the process, foreign particles, particles generated on the electrostatic chuck, or surface damage of the electrostatic chuck during PM progression, or when used for a long time High frequency power causes the electrostatic chuck to fail. The life of electrostatic chucks currently in use is about 1 to 2 years, and most of the failures are due to a decrease in chucking ability due to RF damage or damage to the ceramic surface. When the electrostatic chuck fails in this way, since the electrostatic chuck is formed as one body, the chuck itself needs to be replaced.

It is an object of the present invention to provide an electrostatic chuck consisting of an electrostatic chuck body and a chucking plate which are formed to be disassembleable and coupled.

Another object of the present invention is to provide an electrostatic chuck having a structure such that only the surface portion where the wafer is actually chucked is replaced.

1 shows an electrostatic chuck in accordance with the prior art;

2 is a cross-sectional view showing the structure of an electrostatic chuck according to the prior art;

3 shows an electrostatic chuck in accordance with the present invention; And

4A and 4B are plan views showing the chucking plate and the electrostatic chuck body shown in FIG. 3.

Explanation of symbols on the main parts of the drawings

100: lower electrode 120: electrostatic chuck body

140: chucking plate 160: wafer

(Configuration)

According to a feature of the present invention for achieving the above object, there is provided a semiconductor manufacturing equipment for processing a wafer as a workpiece, the semiconductor manufacturing equipment includes a lower electrode which is supplied with a high frequency power; And an electrostatic chuck coupled to the lower electrode to support the wafer. The electrostatic chuck is composed of an electrostatic chuck body connected to the lower electrode, and a chucking plate connected to the electrostatic chuck body to chuck the wafer. The chucking plate is manufactured to be coupled / disassembled with / from the electrostatic chuck body, and only negative chucking voltages are applied to the chucking plate.

(Action)

According to such a device, since only the chucking plate can be replaced when the electrostatic chuck needs to be replaced due to a decrease in the chucking ability or failure of the electrostatic chuck, fuel costs and equipment down time can be reduced.

(Example)

Preferred embodiments of the invention will be described in detail hereinafter on the basis of reference drawings.

3 is a view showing an electrostatic chuck according to a preferred embodiment of the present invention, Figures 4a and 4b is a view showing the top surface of the electrostatic chuck body and chucking plate shown in FIG.

In Fig. 3, reference numeral "100" denotes a bottom electrode and reference numeral "120" denotes an electrostatic chuck body. Reference numeral 140 denotes a chucking plate, and reference numeral 160 denotes a wafer.

First, referring to FIG. 3, the lower electrode 100 receives high frequency power (RF power), and the electrostatic chuck body 120 is fixed to the lower electrode 100. The electrostatic chuck body 120 is provided with a positive electrode electrode 122 and a negative electrode electrode 124. The chucking plate 160, unlike the electrostatic chuck according to the prior art, will be manufactured to be coupled / disassembled with the electrostatic chuck body 120. Here, the electrostatic chuck body 120 and the chucking plate 140 constitute an electrostatic chuck (ESC).

Unlike the electrostatic chuck according to the prior art, as shown in the drawings, the electrostatic chuck according to the present invention has an electrostatic chuck body 120 connected to the lower electrode 100 and a chucking plate connected to the electrostatic chuck body 120 ( Are divided into two parts. As shown in the drawing, the conventional (-) and (+) electrodes can be connected to the upper side of the electrostatic chuck body 120, and the portions insulated by two parts of (-) and (+) of the conventional electrostatic chuck are electrostatic chucks. (-) And (+) electrode parts are separately manufactured on the upper chucking plate 140 so that the chucking voltage can be applied thereto, and the (-) and (+) electrode parts are not placed on the electrostatic chuck body 120. .

A coolant flow line is fabricated in the electrostatic chuck body 120 to allow the lower temperature to be transmitted to the chucking plate. When high frequency power is applied to the electrostatic chuck body, the electrostatic chuck body 120 should be equipped with an RF CAPASTRIP so that the high frequency power can be efficiently transmitted to the chucking plate. In addition, the chucking plate is made to be detachable from the electrostatic chuck body so that when the electrostatic chuck fails, the chucking plate portion where the wafer is actually chucked can be replaced separately, thereby reducing fuel cost and chuck production cost due to the electrostatic chuck.

In the above, the configuration and operation of the circuit according to the present invention has been shown in accordance with the above description and drawings, but this is only an example, and various changes and modifications can be made without departing from the spirit and scope of the present invention. Of course.

As described above, the electrostatic chuck is divided into two parts and is electrically connected to the lower electrode 100. More specifically, it is divided into an electrostatic chuck body portion capable of receiving high frequency power and a chucking plate portion in which chucking voltage is applied to actually perform chucking. When fabricating a structure in which the positive and negative electrostatic chuck voltages are applied to the positive and negative electrodes of the chucking plate 140, it is necessary to replace the electrostatic chuck due to the chucking ability of the electrostatic chuck or failure. In this case, only the chucking plate can be replaced, thereby reducing fuel costs and downtime.

Claims (2)

In a semiconductor manufacturing facility for processing a wafer as a workpiece: A lower electrode receiving high frequency power; And An electrostatic chuck coupled to the lower electrode and supporting the wafer; The electrostatic chuck is composed of an electrostatic chuck body connected with the lower electrode, and a chucking plate connected with the electrostatic chuck body to chuck the wafer; And the chucking plate is fabricated to be coupled / disassembled from / to the electrostatic chuck body. The method of claim 1, (-) And (+) chucking voltages are applied only to the chucking plate.