EP0494745A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Method of etching and/or leveling the surface of a laminated semiconductor substrate
Assignee: NEC Corp
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Filing: 1992-01-06
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Granted: —
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Expires: 2012-01-06
Abstract
Abstract Disclosed is an improved method of leveling the laminated surface of a semiconductor substrate, which method permits the exact controlling of the eating-out of the lamination on the semiconductor substrate by detecting the sudden change of the amount of the gas resulting from the chemical reaction of the materials of the different layers with particular selected elements of surrounding plasma gas, thus assuring the reproducibility of leveled semiconductor substrate surface.
Inventors
- 👤 Fumihide Sato
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-04 01:45
CPC Classifications
H; H10; H10W; H10W20/00; H10W20/01; H10W20/071; H10W20/092; H10P; H10P50/00; H10P50/20; H10P50/28; H10P50/282; H10P50/283; H10P95/00; H10P95/06; H10P95/062; H10P95/064
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
89 words
A method of etching a surface of a laminated semiconductor substrate, which substrate includes a lower layer and an upper layer upon the lower layer, the upper layer being of a different material from said lower layer, the method comprising subjecting the upper layer to ion etching in a plasma gas atmosphere, detecting the exposure of part of the lower layer by sensing a sudden change in the amount of a constituent of said plasma gas atmosphere caused by said exposure, and controlling the ion etching in response thereto.
Claim 2
Dependent Claim
40 words
A method according to Claim 1 wherein the constituent of said plasma gas atmosphere is a gaseous reaction product resulting from a chemical reaction between the material of a said layer and an original constituent of the plasma gas atmosphere.
Claim 3
Independent Claim
262 words
A method of leveling a surface of a laminated semiconductor substrate comprising the steps of: preparing a semiconductor substrate having a plurality of wiring conductors attached thereto; forming a first insulating film on the surface of the semiconductor substrate and said wiring conductors; forming on said first insulating film, a second insulating film of a material which is different from the material of said first insulating film; forming a coating layer on said second insulating film; subjecting said coating layer to a first ion etching within a first plasma gas atmosphere; detecting the exposure of the part or parts of said second insulating film at its highest level from a sudden change in the amount of a gaseous reaction product resulting from a chemical reaction of the material of said coating layer with a selected constituent of the first plasma gas to stop said first ion etching; subjecting the etched surface to a second ion etching in a second plasma gas atmosphere, the rate at which the material of said second insulating film is eaten out being selected to be larger than the rate at which the material of said coating layer is eaten out; and detecting the exposure of the part or parts of said first insulating film at its highest level from the sudden change in the amount of a gaseous reaction product resulting from a chemical reaction of the material of said first film with a selected element of the second plasma gas to stop said second ion etching, thus substantially leveling the laminated surface of said semiconductor substrate.
Claim 4
Dependent Claim
44 words
A method according to Claim 3 further comprising the steps of: removing the remaining coating material from the upper surface of said second film; and forming an insulating film on said second film and the exposed part or parts of said first insulating film.
Claim 5
Dependent Claim
16 words
A method according to Claim 3 or Claim 4 wherein said second ion etching is anisotropic.
Claim 6
Dependent Claim
16 words
A method according to Claim 3 or Claim 4 wherein said second ion etching is isotropic.
Claim 7
Independent Claim
43 words
A method according to any of Claims 2 to 6 wherein the or a said gaseous reaction product is carbon monoxide, the sudden change in the amount thereof being detected by monitoring the amount of light of wavelength 451nm characteristic of carbon monoxide.
Claim 8
Independent Claim
16 words
A method according to Claims 3 and 7 wherein both gaseous reaction products are carbon monoxide.
Claim 9
Independent Claim
37 words
A method according to Claims 3 and 7 or 8 wherein the second insulating film is of silicon oxide doped with phosphorus and boron, the coating layer is of novolak, and the first plasma gas is oxygen.
Claim 10
Independent Claim
47 words
A method according to Claims 3 and 7 or 8 wherein the first insulating film is of impurity-free silicon oxide, the second insulating layer is of silicon oxide doped with phosphorus and boron, and the second plasma gas is a mixture of CF₄ + CHF₃ + Ar
References Cited (Backward Citations)
No citation records indexed.
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