Sample holding electrode and a plasma processing apparatus using the same

Abstract

A temperature control type sample-holding electrode using a heater capable of enhancing the performance of controlling the electrode temperature and ensuring the uniformity of static adsorption force over the entire surface, the sample-holding electrode being provided in a processing chamber with a sample being disposed thereon, including a dielectric film having a sample-placing surface and a thin electrode film disposed so as to oppose to the sample-placing surface by way of the dielectric film and comprising a layer of a substantially identical height serving both as a static adsorption electrode and a heater electrode, and provided with power source device capable of simultaneously supplying an AC power for heater and DC power for static adsorption to the thin electrode film.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross sectional view for a detailed structure of an electrode of a first embodiment according to the present invention;

FIG. 2 is a cross sectional view showing a first embodiment of a sample-holding electrode using the invention;

FIG. 3 is a view showing a planar structure of the electrode of the first embodiment according to the invention;

FIG. 4 is a view for explaining the operation of static adsorption by a static adsorption area including a non-heater/exclusive adsorption area;

FIG. 5 is a graph showing control examples of temperature distribution on an electrode in a case of using the first embodiment of the invention;

FIG. 6 is a view showing an example of an electrode structure according to a second embodiment of the invention;

FIG. 7 is a view for explaining a detailed structure inside a base electrode according to the second embodiment; and

FIG. 8 is a view showing the operation of electrostatic adsorption in a monopole type electrode.

Claims

1. A sample-holding electrode provided in a processing chamber to which a sample is disposed, the electrode comprising: a dielectric film having a sample-placing surface;a thin electrode film disposed so as to oppose to the sample-placing surface by way of the dielectric film, including a layer having a substantially same height serving both as a static adsorption electrode and a heater electrode; anda power source device capable of simultaneously supplying an AC power for heater and DC power for static adsorption to the thin electrode film.

2. A sample-holding electrode according to claim 1, wherein the thin electrode film comprises a substantially identical metal thin film, andwherein the layer of the metal thin film is put between upper and lower dielectric films and the upper dielectric film has the sample-placing surface.

3. A sample-holding electrode according to claim 2, wherein the metal thin film comprises a laminate structure formed of a flame sprayed film.

4. A sample-holding electrode according to claim 2, wherein the resistivity of the metal thin film formed between the dielectric films is controlled by W or a metal alloy.

5. A sample-holding electrode according to claim 1, wherein the thin electrode film comprises an outer adsorption electrode and an inner adsorption electrode each of a substantially identical area, and includes:common areas disposed to the outer adsorption electrode and the inner adsorption electrode, respectively;at least one branch area connected by way of a bridge portion to at least one of the common areas;a DC power source device for applying a DC power between the outer adsorption electrode and the inner adsorption electrode; andan AC power source device for applying an AC heater power to both ends of each of the common areas.

6. A sample-holding electrode according to claim 5, wherein the common area comprises a band-like electrode area having a predetermined width as a planar shape, which is formed spirally in a circumferential direction by a plurality of turns by way of a radial gap.

7. A sample-holding electrode according to claim 1, wherein the thin electrode film is constituted as a band-like electrode surface capable of substantially covering approximately the entire surface of the sample-placing surface, and has heater terminals by the number of three or more in total disposed to both ends of the continuous band-like electrode surface and between them,the sample-holding electrode comprising:a DC power source device for applying a DC power to the thin electrode film; anda plurality of AC power source devices capable of controlling the output for applying an AC heater power which is connected between the three or more of heater terminals.

8. A plasma processing apparatus comprising: a processing chamber the inside of which is evacuated;a sample-holding electrode provided in the processing chamber with a sample being disposed thereon;an electromagnetic wave generation device for generating plasmas in the processing chamber;a gas supply system for supplying a processing gas into the processing chamber; andan evacuating and exhausting system for exhausting the inside of the processing chamber,wherein the sample-holding electrode includes:a dielectric film having a sample-placing surface;a thin electrode film disposed so as to oppose to the sample-placing surface by way of the dielectric film which has a layer having a substantially same height serving both as a static adsorption electrode and a heater electrode; anda power source device capable of simultaneously supplying an AC power for heater and a DC power for static adsorption to the thin electrode film.

9. A plasma processing apparatus according to claim 8, wherein the thin electrode film comprises an outer adsorption electrode and an inner adsorption electrode each of a substantially identical area, and includes:common areas disposed to the outer adsorption electrode and the inner adsorption electrode respectively;at least one branch area connected by way of a bridge portion to at least one of the common areas; anda DC power source device for applying a DC power between the outer adsorption electrode and the inner adsorption electrode; andan AC power source device for applying a AC heater power to both ends of each of the common areas.

10. A plasma processing apparatus according to claim 8, wherein the thin electrode film is constituted as a band-like electrode surface capable of substantially covering the approximately entire surface of the sample-placing surface, and includes heater terminals by the number of three or more in total disposed to both ends of a continuous band-like electrode surface and between them,the plasma processing apparatus comprising:a DC power source device for supplying a DC power to the thin electrode film; anda plurality of AC power source devices capable of controlling the output for applying an AC heater power which is connected between three or more of the terminals.