Microwave plasma film deposition system

• US 5,125,358 A
• Filed: 07/25/1989
• Issued: 06/30/1992
• Est. Priority Date: 07/26/1988
• Status: Expired due to Term

• Current Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Suzuki, Naoki, Ueda, Tetsuya, Yano, Kohsaku
• Primary Examiner(s): Beck, Shrive
• Assistant Examiner(s): Owens, Terry J.
• Application Number:
  US07/384,699
• Time in Patent Office: 1,071 Days
• Field of Search: 118/723, 156/345, 156/653, 156/656, 315/111.21, 315/111.41, 315/111.71, 427/45.1, 427/39
• US Class Current: 118/723.0MR
• CPC Class Codes: C23C 16/511 using microwave discharges
• CPC Class Codes: H01J 37/32192 Microwave generated discharge H01J37/32357, H01J37/32366, H01J37/32394, H01J37/32403 take precedence
• CPC Class Codes: H01J 37/32211 Means for coupling power to the plasma
• CPC Class Codes: H01J 37/32678 Electron cyclotron resonance

Abstract

A microwave plasma film deposition system comprises a waveguide for feeding microwaves through a microwave feeding window provided at one end of the waveguide, and a plasma cavity in communication with the other end of the waveguide and having a discharge gas inlet which is not in communication with the waveguide. The system further includes a specimen chamber which is in communication with the plasma cavity and which has a substrate setting rest therein and a material gas inlet, and a magnetic field applying device provided near the plasma cavity. Stable film deposition occurs because the plasma cavity is at the end of the waveguide which is remote from the microwave feeding window, whereby deposition on the microwave feeding window is prevented. Deposition on the microwave feeding window is further prevented by a ferromagnetic material which is placed around the waveguide and which reduces the strength of the magnetic field in the waveguide.

Claims

1. A microwave plasma film deposition system, comprising:

a rectangular waveguide for feeding microwaves by way of a microwave feeding window provided at an end thereof, the size of a shorter one of vertical and horizontal sides of a cross-section of said rectangular waveguide being equal to or shorter than the mean free path of an electron of a gas in said rectangular waveguide;

a plasma cavity in communication with another end of said waveguide and further having a discharge gas inlet which is not in communication with said waveguide;

a specimen chamber in communication with said plasma cavity and having a substrate setting rest therein and a material gas inlet; and

magentic field applying means provided near said plasma cavity for generating plasma in said plasma cavity,

wherein the strength B (TESLA) of the magnetic field near said microwave feeding window satisfies the following condition;

space="preserve" listing-type="equation">B<

(1/r)√

(2mT)/e

where 2r is the size of a shorter one of vertical and horizontal sides of a cross-section of said rectangular waveguide;

m (kg) is the mass of the electron;

e (C) is the electric charge of the electron; and

T (eV) is the energy sufficient to ionize the gas.

2. A microwave plasma film deposition system as set forth in claim 1, wherein ferromagnetic material is provided around said rectangular waveguide to lower the strength of a magnetic field in said rectangular waveguide.