US4377627A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Microminiature solid state device manufacture with automatic alignment of sub-patterns
Assignee: USPHILIPS Corp A CORPOF DEL
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Filing: 1980-12-15
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Granted: 1983-03-22
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Expires: 2000-12-15
Abstract
Abstract A semiconductor substrate is mounted in an electron beam image projector with a mask. The patterned electron beam from the mask comprises a first sub-pattern and a second lower intensity sub-pattern. The difference in the intensities of the two sub-patterns permits the automatic alignment of the patterned electron beam relative to the substrate by detecting when the first sub-pattern is incident on a reference marker pattern on the substrate, while the first and second sub-patterns together expose an electron sensitive layer at the entire area of the reference marker pattern. The part of the layer retained after developing can be used as an etchant mask during the definition of a protective layer or the removal of unwanted material from the entire area of the reference marker pattern depending on whether the layer is a negative or a positive electron sensitive material.
Inventors
- 👤 David J. Vinton
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 10:44
CPC Classifications
G; G03; G03F; G03F9/00; G03F9/70; G03F9/7073; G03F9/7076; Y; Y10; Y10S; Y10S430/00; Y10S430/167; Y10S430/168
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
162 words
In a method of manufacturing a microminiature solid state device comprising the step of forming at least one reference marker pattern on a surface of a semiconductor substrate, the improvement comprising the steps of forming said reference marker pattern by exposing a layer of radiation sensitive material on said surface of said substrate to a patterned radiation beam from a mask, said mask passing a first sub-pattern of radiation and a second sub-pattern of radiation having a lower intensity than said first sub-pattern, said first sub-pattern being contained at least within a portion of said second sub-pattern, and said first sub-pattern having substantially the same configuration as said reference marker pattern, aligning said patterned radiation beam from said mask relative to said substrate so that said first sub-pattern is incident on said reference marker pattern, and continuing exposure of said layer to determine a portion of said layer for removal, said layer being defined by the perimeter of said patterned radiation beam.
Claim 2
Dependent Claim
162 words
In a method of manufacturing a microminiature solid state device comprising the step of forming at least one reference marker pattern on a surface of a semiconductor substrate, the improvement comprising the steps of forming said reference marker pattern by exposing a layer of radiation sensitive material on said surface of said substrate to a patterned radiation beam from a mask, said mask passing a first sub-pattern of radiation and a second sub-pattern of radiation having a lower intensity than said first sub-pattern, said first sub-pattern being contained at least within a portion of said second sub-pattern, and said first sub-pattern having substantially the same configuration as said reference marker pattern, aligning said patterned radiation beam from said mask relative to said substrate so that said first sub-pattern is incident on said reference marker pattern, and continuing exposure of said layer to determine a portion of said layer for removal, said layer being defined by the perimeter of said patterned radiation beam.
Claim 3
Dependent Claim
76 words
A method according to claim 1, wherein said first sub-pattern of radiation is obtained through a first portion of said mask consisting essentially of a transparent mask substrate, a transparent conductive layer, and a photocathode layer, and wherein said second sub-pattern of radiation is obtained through a second portion of said mask consisting essentially of said transparent mask substrate, a patterned layer of such thickness to be relatively transparent, said conductive layer, and said photocathode layer.
Claim 4
Dependent Claim
21 words
A method according to claim 2, wherein remaining portions of said mask exclusive of said first and second portions are opaque.
Claim 5
Independent Claim
23 words
A method according to one of claims 2 or 3, wherein said patterned layer of said second portion of said mask is chromium.
Claim 6
Dependent Claim
20 words
A method according to claim 4, wherein said remaining portions are of chromium of thicker amounts than said second portion.
Claim 7
Dependent Claim
12 words
A method according to claim 2, wherein said conductive layer is chromium.
Claim 8
Dependent Claim
21 words
A method according to claim 2, wherein said photocathode layer is a cesium iodide layer formed directly on said conductive layer.
Claim 9
Dependent Claim
29 words
A method according to claim 2, wherein said patterned radiation beam is an electron beam pattern generated by incidence of electromagnetic radiation through said mask on said photocathode layer.
Claim 10
Independent Claim
19 words
A method according to one of claims 1 or 8, wherein said radiation sensitive material is an electron resist.
Claim 11
Dependent Claim
40 words
A method according to claim 9, wherein an X-ray signal is derived from incidence of said first sub-pattern of radiation on said reference marker pattern, said X-ray signal being used to automatically align said first sub-pattern relative to said substrate.
Claim 12
Dependent Claim
36 words
A method according to claim 1, wherein said layer of radiation sensitive material is a positive radiation sensitive material, and said layer is completely removed from the entire area of said reference marker pattern by developing.
Claim 13
Dependent Claim
35 words
A method according to claim 1, wherein said layer of radiation sensitive material is a negative radiation sensitive material, and said layer is completely removed from areas outside of said reference marker pattern by developing.
Claim 14
Dependent Claim
34 words
A method according to claim 1, wherein portions of said layer outside of said reference marker pattern define an aperture corresponding to an area of said substrate where other processing steps may be effected.
Claim 15
Dependent Claim
64 words
A method according to claim 1, wherein said reference marker pattern is obtained by the steps of exposing a preliminary layer of said radiation sensitive material to said patterned radiation beam, developing said preliminary layer to completely remove a portion defined by the perimeter of said first sub-pattern, and forming said reference marker pattern at locations defined by remaining portions of said preliminary layer.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-03-21 | 1986-09-20 | 1987-03-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-03-21 | 1990-09-20 | 1991-03-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-03-21 | 1994-09-20 | 1995-03-22 | $7700.00 | Window Closed / Lapsed |