JPH04348543A - Electrostatic attraction device - Google Patents

Abstract

PURPOSE:To maintain an attraction force, by which a substrate is held, constant by providing this device with a DC controller for controlling a dc power supply which makes the potential of a lower electrode on which a semiconductor substrate is mounted, constant. CONSTITUTION:A voltmeter 5 which measures the potential of a lower electrode 4 and a DC controller 6 which receives the input of voltage of the lower electrode 4 and controls application voltage of a dc power supply 11 are installed. With installation of the controller 6, the potential of the lower electrode 4 varies depending on the etching conditions. However, the DC controller 6 can correct the application voltage and make it constant at all times. Therefore, an attraction force by which a semiconductor substrate 3 is held can be made constant. A temperature transmission efficiency can be stabilized, too.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrostatic chuck device for improving the degree of contact between the surface of a lower electrode on which a semiconductor substrate is placed and a semiconductor substrate in a plasma etching apparatus.

0002

2. Description of the Related Art FIG. 2 is a sectional view showing a plasma etching apparatus using an example of a conventional electrostatic chuck apparatus. Usually, as shown in FIG. 2, a plasma etching apparatus includes a vacuum processing chamber 2 that houses a semiconductor substrate 3 and is evacuated through an exhaust hole 7, and into which gas is introduced through a gas inlet 1 and replaced with the gas. , an electrostatic adsorption device consisting of a lower electrode 4 and a DC power supply 11 that applies a DC voltage to the lower electrode, and a high-frequency voltage applied between the upper electrode and the lower electrode 4 to convert the introduced gas into plasma. The high-frequency power source 9 is equipped with a high-frequency power source 9.

When etching the semiconductor substrate 3 using this plasma etching apparatus, first, the lower electrode 4 is etched.
After placing the semiconductor substrate on the
1, a constant DC voltage was applied to attract and hold the semiconductor substrate 3 to the lower electrode 4, and then plasma etching was performed.

0004

Problems to be Solved by the Invention In the above-described conventional electrostatic adsorption device, since the potential of the lower electrode differs when the etching processing conditions differ, the degree of adsorption of the semiconductor substrate also differs. Therefore, there is a problem that the heat transfer efficiency for transmitting the temperature of the lower electrode to the semiconductor substrate is not constant, and there is a drawback that desired etching cannot be obtained.

[0005] The purpose of the present invention is to solve such problems,
An object of the present invention is to provide an electrostatic adsorption device that stabilizes the degree of adsorption and keeps heat transfer efficiency constant.

[0006]

[Means for Solving the Problems] The electrostatic adsorption device of the present invention provides a direct current voltage applied to a lower electrode on which a semiconductor substrate is placed in a plasma ion etching device that etches a semiconductor substrate by plasma ionizing introduced gas. The control device is provided with a control device that detects the potential of and inputs the detected potential to keep the applied potential constant.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a sectional view showing a plasma etching apparatus using an electrostatic chuck device according to an embodiment of the present invention. As shown in FIG. 1, this electrostatic adsorption device includes a voltmeter 5 that measures the potential of the lower electrode 4, and a DC control device 6 that inputs the voltage of the lower electrode 4 and controls the applied voltage of the DC power source 11. This is because we have established the following. Other than that, it is the same as before.

By providing this DC control device 6, even if the potential of the lower electrode 4 changes depending on the etching process conditions, the DC control device 6 can correct the applied voltage and maintain it at a constant voltage at all times. Therefore, the semiconductor substrate 3
It is possible to keep the adsorption force that holds the temperature constant, and the temperature transfer efficiency can be stabilized.

Further, although this electrostatic chuck device has been described in an embodiment in which it is applied to a plasma etching device using a high frequency power source, it is clear that it can also be applied to a plasma etching device using a micro type.

[0011]

As explained above, the present invention provides a DC control device that controls the DC power supply to keep the potential constant while measuring the potential of the lower electrode on which the semiconductor substrate is placed. This has the effect of providing an electrostatic adsorption device that can maintain a constant adsorption force for holding the semiconductor substrate and maintain a constant heat transfer efficiency of heat transferred to the semiconductor substrate.

[Brief explanation of drawings]

FIG. 1 is a schematic cross-sectional view showing a plasma etching apparatus using an electrostatic adsorption device according to an embodiment of the present invention.

FIG. 2 is a schematic cross-sectional view showing a plasma etching apparatus using an example of a conventional electrostatic chuck device.

[Explanation of symbols]

1 Gas inlet 2 Vacuum processing chamber 3 Semiconductor substrate 4 Lower electrode 5 Voltmeter 6 DC control device 7 Exhaust port 9 High frequency power supply 11 DC power supply

Claims (1)

[Claims] 1. Detecting the potential of a DC voltage applied to a lower electrode on which the semiconductor substrate is placed in a plasma ion etching apparatus that etches a semiconductor substrate by plasma ionizing an introduced gas, and inputting the detected potential. An electrostatic adsorption device comprising: a control device that keeps the applied potential constant.