Patent EP0097903A2 successfully refreshed from Google Patents.
EP0097903A2
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Method of electron beam exposure
Assignee: Toshiba Corp
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Filing: 1983-06-20
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Granted: —
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Expires: 2003-06-20
Abstract
Abstract A method of electron beam exposure comprising selectively exposing a resist film on a substrate (34) a plurality of times with an electron beam whose dose is lower than a desired dose sufficient to produce a difference in molecular weight between the exposed area and nonexposed area, the cumulative dose corresponding to said desired dose.
Inventors
- 👤 Fumio Komatsu
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-26 10:32
CPC Classifications
H; H10; H10P; H10P95/00; B; B82; B82Y; B82Y10/00; B82Y40/00; H01; H01J; H01J37/00; H01J37/30; H01J37/317; H01J37/3174; H01J2237/00; H01J2237/30; H01J2237/317; H01J2237/3175; H01J2237/31769; H01J2237/31771
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
56 words
A method of electron beam exposure comprising selectively exposing a resist film on a substrate (34) a plurality of times with an electron beam whose dose is lower than a desired dose sufficient to produce a difference in molecular weight between an exposed area and a nonexposed area, the cumulative dose corresponding to said desired dose.
Claim 2
Independent Claim
56 words
A method of electron beam exposure comprising selectively exposing a resist film on a substrate (34) a plurality of times with an electron beam whose dose is lower than a desired dose sufficient to produce a difference in molecular weight between an exposed area and a nonexposed area, the cumulative dose corresponding to said desired dose.
Claim 3
Dependent Claim
15 words
A method according to claim 1, characterized in that said substrate is a silicon wafer.
Claim 4
Dependent Claim
16 words
A method according to claim 1, characterized in that said substrate (34) is a blank mask.
Claim 5
Dependent Claim
45 words
A method according to claim 1, characterized in that said electron beam exposing step is effected a plurality of steps with a beam current lower in level than the level of a desired beam current, the cumulative current level corresponding to said desired beam current.
Claim 6
Dependent Claim
30 words
A method according to claim 4, characterized in that said resist film is exposed twice with a beam current whose level is one half that of said desired beam current.
Claim 7
Dependent Claim
30 words
A method according to claim 4, characterized in that a resist film is exposed thrice with a beam current level which is one-third the level of said desired beam current.
Claim 8
Dependent Claim
32 words
A method according to claim 1, characterized in that said exposing step is performed a plurality of times on the resist film with an exposure time shorter than a desired exposure time.
Claim 9
Dependent Claim
29 words
A method according to claim 7, characterized in that said exposing step is performed twice on the resist film with an exposure time one half the desired exposure time.
Claim 10
Dependent Claim
29 words
A method according to claim 7, characterized in that said exposing step is performed thrice on the resist film with an exposure time one-third of the desired exposure time.
References Cited (Backward Citations)
No citation records indexed.
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