Plasma processing apparatus and plasma processing method

• US 6,528,752 B1
• Filed: 06/16/2000
• Issued: 03/04/2003
• Est. Priority Date: 06/18/1999
• Status: Expired due to Fees

• Current Assignee: Makoto Ando, Naohisa Goto, Tokyo Electron Limited, Yasuyoshi Yasaka
• Original Assignee: Makoto Ando, Naohisa Goto, Tokyo Electron Limited, Yasuyoshi Yasaka
• Inventors: Yasaka, Yasuyoshi, Ando, Makoto, Goto, Naohisa, Ishii, Nobuo
• Primary Examiner(s): Walberg, Teresa
• Assistant Examiner(s): VAN, QUANG T
• Application Number:
  US09/595,476
• Time in Patent Office: 991 Days
• Field of Search: 219/121.43, 219/121.54, 219/121.48, 219/745-750, 156/345, 118/723.MN, 118/723.AN, 118/723.IR, 118/723.VE, 118/50.1, 373/18, 373/25, 315/111.81, 315/111.21, 427/8
• US Class Current: 219/121.43
• CPC Class Codes: H01J 37/32082 Radio frequency generated discharge H01J37/32357, H01J37/32366, H01J37/32394 and H01J37/32403 take precedence
• CPC Class Codes: H01J 37/321 the radio frequency energy being inductively coupled to the plasma
• CPC Class Codes: H01J 37/32568 Relative arrangement or disposition of electrodes; moving means

Abstract

A plasma-assisted processing system has a lifting mechanism capable of vertically moving a microwave power unit and a waveguide to adjust the level of a planar slot antenna disposed on an expanded lower end part of the waveguide. A space extending under the antenna is surrounded by a shielding member. An optical sensor having an array of photosensors is disposed on the outer side of a window formed in the side wall of a vacuum vessel to monitor the lower limit level of a cease region for a plasma (cease level). An ideal distance between the cease level and the antenna is determined beforehand and the level of the antenna is adjusted on the basis of a measured cease level so that the antenna is spaced the ideal distance apart from the cease level. Since the difference between the cease level and a level X0 for the cutoff density of an X-wave is fixed, the level X0 may be monitored instead of the cease level.

Claims

1. A plasma-assisted processing system comprising:

a vacuum vessel internally provided with a stage;

a high-frequency wave transmitting plate attached to the vacuum vessel;

a planar antenna disposed opposite to the high-frequency wave transmitting plate;

a high-frequency power unit for delivering to the planar antenna a high-frequency wave for producing a plasma;

a lifting mechanism for moving the planar antenna vertically relative to the vacuum vessel;

an electromagnetic shielding member surrounding a region between the planar antenna and the high-frequency wave transmitting plate;

a storage unit for storing antenna levels of recipes for plasma-assisted processing; and

a controller for reading a level of the planar antenna for a selected recipe from the storage unit and for controlling the lifting mechanism to adjust the level of the planar antenna,

wherein the plasma-assisted processing system propagates a high-frequency wave for producing a plasma through the planar antenna and the high-frequency wave transmitting plate into the vacuum vessel, produces a plasma by ionizing a processing gas supplied into the vacuum vessel by energy from the high-frequency wave, and processes a substrate mounted on the stage in the vacuum vessel by using the plasma.