US5407786A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of forming a mask on a semiconductor substrate via photosensitive resin deposition, ammonia treatment and selective silylation
Assignee: Toshiba Corp
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Filing: 1992-12-14
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Granted: 1995-04-18
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Expires: 2012-12-14
Abstract
Abstract A photosensitive organic resin layer is formed on a semiconductor substrate. The resin layer is treated with ammonia before or after the resin layer is exposed. Then, the exposed organic resin layer is easily silylated. Due to the ammonia treatment, non-exposed portions of the organic resin layer is hardly silylated so that a high aspect ratio of patterning is realized.
Inventors
- 👤 Shinishi Ito
- 👤 Haruo Okano
- 👤 Makoto Nakase
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 18:52
CPC Classifications
G; G03; G03F; G03F7/00; G03F7/26; G03F7/265
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
108 words
A method of forming a mask on a semiconductor substrate comprising the steps of: coating a substrate with a film made of a photosensitive organic resin; partially exposing said film to light in order to develop said photosensitive resin in accordance with the pattern of a mask; applying ammonia to said film to decompose a carboxylic acid occurring in said photosensitive resin; applying a silicon compound to said film to silylate said photosensitive resin exposed to light; and removing said developed photoresist resin by etching in order to leave said pattern of said mask in said film wherein said ammonia is applied before application of the silicon compound.
Claim 2
Independent Claim
108 words
A method of forming a mask on a semiconductor substrate comprising the steps of: coating a substrate with a film made of a photosensitive organic resin; partially exposing said film to light in order to develop said photosensitive resin in accordance with the pattern of a mask; applying ammonia to said film to decompose a carboxylic acid occurring in said photosensitive resin; applying a silicon compound to said film to silylate said photosensitive resin exposed to light; and removing said developed photoresist resin by etching in order to leave said pattern of said mask in said film wherein said ammonia is applied before application of the silicon compound.
Claim 3
Dependent Claim
13 words
The method as claimed in claim 1, wherein said silicon compound is hexamethyldisilazane.
Claim 4
Dependent Claim
20 words
The method as claimed in claim 1, wherein said photosensitive resin is composed of novolac resin and a photosensitive material.
Claim 5
Dependent Claim
24 words
The method as claimed in claim 1, wherein said ammonia is applied to said resin at a temperature of no lower than 60° C.
Claim 6
Dependent Claim
36 words
The method as claimed in claim 1, wherein said ammonia is applied to said resin in a chamber at a negative pressure in which said substrate is heated at a temperature of 50° to 120° C.
Claim 7
Dependent Claim
26 words
The method as claimed in claim 1, wherein said step of removing said developed photoresist resin is carried out by reactive ion etching with oxygen plasma.
Claim 8
Dependent Claim
27 words
The method as claimed in claim 6, wherein said oxygen plasma is generated by applying high frequency voltage between parallel plate electrodes provided in a vacuum chamber.
Claim 9
Dependent Claim
16 words
The method as claimed in claim 1, wherein said ammonia is applied after the exposing step.
Claim 10
Dependent Claim
16 words
The method as claimed in claim 1, wherein said ammonia is applied before the exposing step.
Claim 11
Dependent Claim
15 words
The method as claimed in claim 1, wherein said ammonia decarboxylates said developed photosensitive resin.
Claim 12
Dependent Claim
24 words
The method as claimed in claim 1, wherein the application of said ammonia suppresses absorption of said silicon compound into the non-developed photosensitive resin.
Claim 13
Independent Claim
103 words
A method of forming a mask on a semiconductor substrate comprising the steps of: coating a substrate with a film made of a photosensitive organic resin; partially exposing said film to light in order to develop said photosensitive resin in accordance with the pattern of a mask; catalyzing decomposition of carboxylic acid in said photosensitive resin with ammonia; silylating said photosensitive resin exposed to light with a silazane compound; and removing said developed photoresist resin by etching in order to leave said pattern of said mask in said film wherein said silylation step is accelerated by the decomposition of carboxylic acid with ammonia.
Claim 14
Independent Claim
103 words
A method of forming a mask on a semiconductor substrate comprising the steps of: coating a substrate with a film made of a photosensitive organic resin; partially exposing said film to light in order to develop said photosensitive resin in accordance with the pattern of a mask; catalyzing decomposition of carboxylic acid in said photosensitive resin with ammonia; silylating said photosensitive resin exposed to light with a silazane compound; and removing said developed photoresist resin by etching in order to leave said pattern of said mask in said film wherein said silylation step is accelerated by the decomposition of carboxylic acid with ammonia.
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