US5942373A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pattern or via structure formed through supplemental electron beam exposure and development to remove image residue
Assignee: Fujitsu Ltd
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Filing: 1998-01-26
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Granted: 1999-08-24
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Expires: 2018-01-26
Abstract
Abstract Methods of forming patterns in photo-sensitive resist layers with high aspect ratio features are described. The photosensitive layer is patterned exposed to actinic radiation and thereafter developed. For high aspect ratio patterns, the inventors have often observed a residue of resist material at the bottom of such features, and that this residue interferes with subsequent processing, such as filling the pattern with metal by a plating operation. To remove this residue, the patterned locations of the resist are exposed to a low dose of low-energy electron beam radiation, preferably having energy of less than 6 KeV and dosage of less than 200 μC/cm 2 . After the electron beam exposure, the aperture is again exposed to a developer solution, which may be of the same composition as the developer initially used to develop the patterns.
Inventors
- 👤 William T. Chou
- 👤 Solomon I. Beilin
- 👤 Wen-chou Vincent Wang
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 16:16
CPC Classifications
G; G03; G03F; G03F7/00; G03F7/26; G03F7/40; G03F7/20; G03F7/2022; G03F7/2026; Y; Y10; Y10S; Y10S430/00; Y10S430/143
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
141 words
An article made by a photo-process, the photo-process comprising: depositing a photo-sensitive resist layer having a thickness greater than about 60 microns; exposing the photo-sensitive resist layer having a thickness greater than about 60 microns to a pattern of actinic radiation where a via structure is to be formed; developing the pattern exposed resist layer to form said via structure, said via structure being developed such that a residue of resist material remains at the bottom of said via structure; exposing said via structure to electron beam radiation having energy of less than about 6 KeV and dosage of less than about 200 μC/cm 2 to render said residue soluble in a developer solution; and thereafter developing the pattern exposed resist layer a second time such that said residue of resist material is removed from the bottom of said via structure.
Claim 2
Dependent Claim
141 words
An article made by a photo-process, the photo-process comprising: depositing a photo-sensitive resist layer having a thickness greater than about 60 microns; exposing the photo-sensitive resist layer having a thickness greater than about 60 microns to a pattern of actinic radiation where a via structure is to be formed; developing the pattern exposed resist layer to form said via structure, said via structure being developed such that a residue of resist material remains at the bottom of said via structure; exposing said via structure to electron beam radiation having energy of less than about 6 KeV and dosage of less than about 200 μC/cm 2 to render said residue soluble in a developer solution; and thereafter developing the pattern exposed resist layer a second time such that said residue of resist material is removed from the bottom of said via structure.
Claim 3
Dependent Claim
22 words
The article of claim 1 wherein the energy of the electron beam radiation is between about 2 KeV and about 4 KeV.
Claim 4
Dependent Claim
25 words
The article of claim 1 wherein the dosage of the electron beam radiation is between about 50 μC/cm 2 and about 150 μC/cm 2 .
Claim 5
Dependent Claim
24 words
The article of claim 1 wherein exposing said via structure to electron beam radiation includes exposing the entire resist layer to electron beam radiation.
Claim 6
Dependent Claim
25 words
The article of claim 1 further comprising plating a conductive material within said via structure after developing the pattern exposed resist layer a second time.
Claim 7
Dependent Claim
30 words
The article of claim 1 wherein depositing a photo-sensitive resist layer comprises depositing the resist layer on a substrate selected from the group consisting of silicon, gallium arsenide, and alumina.
Claim 8
Dependent Claim
33 words
The article of claim 1 wherein depositing a photo-sensitive resist layer comprises depositing the resist layer on a substrate having a density at least two times the density of the deposited resist layer.
Claim 9
Dependent Claim
144 words
An article made by a photo-process, the photo-process comprising: depositing a photo-sensitive resist layer having a thickness greater than about 60 microns; exposing the resist layer having a thickness greater than about 60 microns to a pattern of actinic radiation; developing the pattern exposed resist layer to form a plurality of apertures, said plurality of apertures being developed such that at least one aperture includes a residue of resist material; exposing the developed resist layer and the plurality of apertures to electron beam radiation having energy of less than about 6 KeV and dosage of less than about 200 μC/cm 2 to render said residue of resist material soluble in a developer solution; and thereafter contacting the resist layer and said residue of resist material with a developer solution such that said residue of resist material is removed from the at least one aperture.
Claim 10
Dependent Claim
144 words
An article made by a photo-process, the photo-process comprising: depositing a photo-sensitive resist layer having a thickness greater than about 60 microns; exposing the resist layer having a thickness greater than about 60 microns to a pattern of actinic radiation; developing the pattern exposed resist layer to form a plurality of apertures, said plurality of apertures being developed such that at least one aperture includes a residue of resist material; exposing the developed resist layer and the plurality of apertures to electron beam radiation having energy of less than about 6 KeV and dosage of less than about 200 μC/cm 2 to render said residue of resist material soluble in a developer solution; and thereafter contacting the resist layer and said residue of resist material with a developer solution such that said residue of resist material is removed from the at least one aperture.
Claim 11
Dependent Claim
22 words
The article of claim 8 wherein the energy of the electron beam radiation is between about 2 KeV and about 4 KeV.
Claim 12
Dependent Claim
25 words
The article of claim 8 wherein the dosage of the electron beam radiation is between about 50 μC/cm 2 and about 150 μC/cm 2 .
Claim 13
Dependent Claim
19 words
The article of claim 8 wherein the at least one aperture includes a width less than about 10 microns.
Claim 14
Dependent Claim
32 words
The article of claim 8 further comprising plating a conductive material within said at least one aperture after contacting the resist layer and said residue of resist material with a developer solution.
Claim 15
Dependent Claim
30 words
The article of claim 8 wherein depositing a photo-sensitive resist layer comprises depositing the resist layer on a substrate selected from the group consisting of silicon, gallium arsenide, and alumina.
Claim 16
Dependent Claim
33 words
The article of claim 8 wherein depositing a photo-sensitive resist layer comprises depositing the resist layer on a substrate having a density at least two times the density of the deposited resist layer.
Claim 17
Dependent Claim
162 words
An article made by a photo-process, the photo-process comprising: depositing a photo-sensitive resist layer having a thickness greater than about 60 microns on a substrate; exposing the photo-sensitive resist layer having a thickness greater than about 60 microns to a pattern of actinic radiation where a via structure having a width of less than about 10 microns wide is to be formed; developing the pattern exposed resist layer to form said via structure having a width less than about 10 microns, said via structure being developed such that a residue of resist material remains at the bottom of said via structure; exposing said via structure to electron beam radiation having energy of less than about 6 KeV and dosage of less than about 200 μC/cm 2 to render said residue soluble in a developer solution; and thereafter developing the pattern exposed resist layer a second time such that said residue of resist material is removed from the bottom of said via structure.
Claim 18
Dependent Claim
162 words
An article made by a photo-process, the photo-process comprising: depositing a photo-sensitive resist layer having a thickness greater than about 60 microns on a substrate; exposing the photo-sensitive resist layer having a thickness greater than about 60 microns to a pattern of actinic radiation where a via structure having a width of less than about 10 microns wide is to be formed; developing the pattern exposed resist layer to form said via structure having a width less than about 10 microns, said via structure being developed such that a residue of resist material remains at the bottom of said via structure; exposing said via structure to electron beam radiation having energy of less than about 6 KeV and dosage of less than about 200 μC/cm 2 to render said residue soluble in a developer solution; and thereafter developing the pattern exposed resist layer a second time such that said residue of resist material is removed from the bottom of said via structure.
Claim 19
Dependent Claim
22 words
The article of claim 15 wherein the energy of the electron beam radiation is between about 2 KeV and about 4 KeV.
Claim 20
Dependent Claim
25 words
The article of claim 15 wherein the dosage of the electron beam radiation is between about 50 μC/cm 2 and about 150 μC/cm 2 .
Claim 21
Dependent Claim
24 words
The article of claim 15 wherein exposing said via structure to electron beam radiation includes exposing the entire resist layer to electron beam radiation.
Claim 22
Dependent Claim
25 words
The article of claim 15 further comprising plating a conductive material within said via structure after developing the pattern exposed resist layer a second time.
Claim 23
Dependent Claim
35 words
The article of claim 15 wherein the substrate includes a density at least two times the density of the deposited resist layer, the substrate selected from the group consisting of silicon, gallium arsenide, and alumina.
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