JPH01315935A - Wafer fixing method by electrostatic chuck - Google Patents

Abstract

PURPOSE:To radiate the heat in a substrate wafer easily by covering an electrode to generate the electrostatic force of an electrostatic chuck with an insulator with the thermal conductivity higher than that of the water. CONSTITUTION:A charged beam exposure device lets flow the charged beams 11a emitted from a charge beam gun 11 to a radiation lens, a reforming lens, a contraction lens, an object lens, and a position deflector, and the beams 11a are radiated on a resist 15 on a wafer 14 fixed to an electrostatic chuck 13 by an electro-static force generated by applying a voltage to the electrode 13b of the electrostatic chuck 13, and exposed. An insulator 13a to cover the electrode 13b of the electrostatic chuck 13 is formed of an insulator with the thermal conductivity higher than that of the water 14, and the heat accumulated on the substrate wafer 14 by the charged beams 11a can be radiated easily through the insulator 13a. Consequently, a desired pattern 15a can be obtained in a good condition.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method of fixing a wafer using an electrostatic chuck, in which a wafer is fixed by electrostatic force.

[Prior art] Conventionally, in the method of fixing and covering a wafer using electrostatic force using an electrostatic chuck, the electrode part to which voltage is applied is coated with an insulator with low thermal conductivity such as alumina, and the It was fixed.

[Invention or problem to be solved] When an insulator such as alumina (21 W/m-K at room temperature) whose thermal conductivity is lower than that of the wafer (188 W/m-K at room temperature) is used to cover the electrode part, The heat accumulated in the substrate wafer becomes difficult to dissipate through the insulator, and when used in a charged beam exposure system, it is used for resist shapes on the substrate wafer or thin film after exposure and development, or for etching equipment. In this case, the heat remaining in the substrate wafer affects the etched shape of the substrate or thin film after etching, making it impossible to obtain a good shape.

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for fixing a wafer using an electrostatic chuck, which can solve these conventional problems and easily dissipate heat within a substrate wafer.

[Means for Solving the Problems] The present invention provides an electrostatic chip 1 in which a wafer is fixed by electrostatic force.
A wafer fixing method using an electrostatic chuck is characterized in that an electrode portion of the electrostatic chuck that generates electrostatic force is coated with an insulator having higher thermal conductivity than the wafer.

The insulator that can be used in the present invention only needs to have a thermal conductivity higher than that of the wafer at room temperature, which is 168 W/m, and includes, for example, a single crystal or polycrystalline material such as carbon.

[Function] In the present invention, by using an insulator having a higher thermal conductivity than the wafer for the test of the electrode section to which voltage is applied, the heat within the substrate wafer can be easily dissipated through the insulator. It becomes possible.

Therefore, even when used in an exposure device or an etching device, no heat remains in the wafer, and the shape or etching shape can be reduced by 1q.

[Example] Hereinafter, an example in which the wafer fixing method according to J-1 of the present invention is used in a charged beam exposure apparatus that exposes and covers a desired pattern using a charged beam will be described with reference to the drawings. Cover detailed explanation.

In FIG. 1, a suspension-resistant optical device transmits an electric beam 11a emitted from a charged beam gun 11 through an irradiation lens, a shaping lens, a reduction lens, a mirror lens, etc. Through the position deflector, the electrostatic force generated by applying a voltage to the J□-□y rack 3 from the power supply 12 to the electrostatic chip (on the wafer 14 fixed to the rack 13) The lens (~15) is irradiated with light in a desired pattern 15a.The insulator 13a covering the electrostatic charge (electrode portion 131 of the cap 13) is an insulator with higher thermal conductivity than the wafer. The heat accumulated on the substrate wafer 14 by the charged beam lla is
Heat can be easily radiated through the insulator 13a, and the desired pattern 15a can be obtained in good condition.

[Effect of the invention] As explained above, according to the method of the present invention, the voltage is reduced to 1
j11 Electrical (Wafer J-
J
It is possible to easily dissipate the heat within the substrate through the insulator. Therefore, when this method is applied to various devices, it is possible to avoid the inconvenience caused by residual heat in the substrate wafer, and it is possible to achieve the intended purpose without any problems.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing an embodiment of the present invention. DESCRIPTION OF SYMBOLS 11... Charged beam gun 11a... Charged beam 12... Power supply 13... Electrostatic chuck 13a... Insulator 13b... Electrode section 14
... Board top C 15... Lenses 1 to 15a
...desired pattern

Claims (1)

[Claims] (1) A wafer fixing method using an electrostatic chuck in which the wafer is fixed by electrostatic force is characterized in that the electrode part of the electrostatic chuck that generates the electrostatic force is covered with an insulator having higher thermal conductivity than the wafer. A wafer fixing method using an electrostatic chuck.