EP0045639A2
Expired / Lapsed
EP
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Method of forming a microscopic pattern
Assignee: Hitachi Ltd
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Filing: 1981-07-31
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Granted: —
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Expires: 2001-07-31
Abstract
Abstract A negative photoresist (5) having bezene rings is irradiated with short-wavelength ultraviolet radiation. Because the benzene rings greatly absorb this radiation on developing a photoresist pattern is formed where sectional shape is an inverted trapezoid. An aluminum layer (4) is deposited, and is discontinuous because of the overhanging edges of the trapezoidal photoresist patterns. On removal of the photoresist, the layer (4) thereon is also lifted off, to leave an aluminum pattern of high precision without the troublesome steps which the lift-off process has heretofore entailed.
Inventors
- 👤 Toshiharu Matsuzawa
- 👤 Kikuo Douta
- 👤 Takao Iwayanagi
- 👤 Hiroshi Yanagisawa
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-29 14:47
CPC Classifications
G; G03; G03F; G03F7/00; G03F7/004; G03F7/038; G03F7/008; G03F7/012; G03F7/0125
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
140 words
A method of forming a microscopic pattern, including the steps of a) depositing a film (5) of a photoresist on a surface (1) on which the microscopic pattern is to be formed, b) irradiating a desired part of the photoresist film (5) to lower the solubility of the irradiated part, c) developing the photoresist film (5) to remove the unirradiated part thereof and to form a photoresist pattern whose sectional shape includes overhanging portions, d) depositing a film (4) of a material which is to form the microscopic pattern, and e) removing the photoresist pattern along with the film (4) deposited thereon, characterised in that the photoresist (5) is a material having benzene rings, which is irradiated with short-wavelenth ultraviolet radiation and then developed to produce a photoresist pattern whose sectional shape is of the form of an inverted trapezoid
Claim 2
Independent Claim
140 words
A method of forming a microscopic pattern, including the steps of a) depositing a film (5) of a photoresist on a surface (1) on which the microscopic pattern is to be formed, b) irradiating a desired part of the photoresist film (5) to lower the solubility of the irradiated part, c) developing the photoresist film (5) to remove the unirradiated part thereof and to form a photoresist pattern whose sectional shape includes overhanging portions, d) depositing a film (4) of a material which is to form the microscopic pattern, and e) removing the photoresist pattern along with the film (4) deposited thereon, characterised in that the photoresist (5) is a material having benzene rings, which is irradiated with short-wavelenth ultraviolet radiation and then developed to produce a photoresist pattern whose sectional shape is of the form of an inverted trapezoid
Claim 3
Dependent Claim
40 words
A method of forming a microscopic pattern as defined in claim 1, wherein said photoresist (5) is selected from poly(vinyl phenol), bromides of poly(vinyl phenol),.poly(vinyl hydroxybenzoate), poly(vinyl hydroxybenzal), poly(isopropenyl phenol) and addition condensation products between phenols or cresols and formaldehyde.
Claim 4
Dependent Claim
23 words
A method of forming a microscopic pattern as defined in claim 1 or claim 2, wherein said photoresist (5) contains an aromatic azide.
Claim 5
Dependent Claim
88 words
A method of forming a microscopic pattern as defined in claim 3, wherein said aromatic azide has a composition which is represented by a general formula: (where letter A denotes an element or substituent unconjugate with two benzene rings, such as 0, S, CH 2 , C 2 H 4 , SO 2 and S 2 , letter.X denotes H or N 3 , and letter Z denotes a substituent N 3 when X is H and an element H or Cl when X is N 3 ).
Claim 6
Dependent Claim
39 words
A method of forming a microscopic pattern as defined in claim 4, wherein the aromatic azide is 4, 4' - diazidephenylsulfide, 4,4' - diazidephenylsulfone, 3,3'-diazidephenylsulfone, 4,4' - diazidediphenylmethane, 3,3' -dichloro-4,4'-diazidediphehylmethane, 4,4' - diazidephenylether, 4,4' - diazidephenyldisulfide, or 4,4' -.diazidebibenzyl.
References Cited (Backward Citations)
No citation records indexed.
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