EP0470707A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Method of patterning a layer
Assignee: AT&T Inc
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Filing: 1991-07-11
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Granted: —
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Expires: 2011-07-11
Abstract
Abstract An antireflection coating (16) for use with a photolithographic process comprises a layer of organic material that planarizes the surface upon which a photoresist layer (21) is deposited, is highly absorptive of deep ultraviolet actinic light, and can be plasma etched along with an underlying metal layer (11), thereby obviating the need for a separate step to remove the exposed antireflection coating prior to metal etch. <IMAGE>
Inventors
- 👤 David H. Ziger
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-31 12:46
CPC Classifications
H; H10; H10P; H10P76/00; H10P76/20; H10P76/204; H10P76/2041; H10P76/2043; G; G03; G03F; G03F7/00; G03F7/004; G03F7/09; G03F7/091; Y; Y10; Y10S; Y10S438/00; Y10S438/942; Y10S438/948; Y10S438/952
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
158 words
A method for making semiconductor devices comprising the steps of: making a first layer on a surface of a substrate; coating the first layer with an antireflection coating; coating the antireflection coating with a photoresist coating; exposing the photoresist coating to deep ultraviolet actinic light which is not efficiently reflected by the antireflection coating; developing the photoresist to define therein a pattern; and using the pattern to define portions of semiconductor devices; characterized in that: the antireflection coating comprises an organic material that is coated on a substrate by depositing it in a fluid form on the substrate, spinning the substrate to distribute the organic material, then hardening the organic material prior to coating with the photoresist layer; the hardened antireflection coating is absorptive of the deep ultraviolet actinic light and is amenable to plasma etching; and the first layer and the antireflection coating are simultaneously plasma etched at regions exposed by the pattern of the photoresist layer.
Claim 2
Dependent Claim
60 words
The method of claim 1 further characterized in that: the first layer has a non-planar upper surface due to surface irregularities; the fluid antireflection coating has a thickness greater than the heights of the surface irregularities; and after spinning, the fluid antireflection coating is allowed to settle sufficiently prior to hardening that its upper surface is substantially planar after hardening.
Claim 3
Dependent Claim
28 words
The method of claim 1 further characterized in that: the fluid organic material is a polymer precursor, and the hardening step comprises a step of polymerizing the precursor.
Claim 4
Dependent Claim
33 words
The method of claim 1 further characterized in that: the fluid antireflection coating is a polymer dissolved in a liquid carrier; and the hardening step comprises the step of evaporating the liquid carrier.
Claim 5
Dependent Claim
13 words
The method of claim 4 further characterized in that: the polymer is polybutylsulfone.
Claim 6
Dependent Claim
17 words
The method of claim 3 further characterized in that: the polymer precursor is a precursor of polysulfone.
Claim 7
Dependent Claim
17 words
The method of claim 3 further characterized in that: the polymer precursor is a precursor of polyaldehyde.
References Cited (Backward Citations)
No citation records indexed.
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