EP0753764A1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Improvements in or relating to semiconductor devices
Assignee: Texas Instruments Inc
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Filing: 1996-07-15
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Granted: —
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Expires: 2016-07-15
Abstract
Abstract An isotropic or partially isotropic etch shrinks lithographically patterned photoresist (211, 212) to yield reduced linewidth patterned photoresist (213, 214) with a buried antireflective coating also acting as an etchstop or a sacrificial layer. The reduced linewidth pattern (213, 214) provide an etch mask for subsequent anisotropic etching of underlying material such as polysilicon (206) or metal or insulator or ferroelectric.
Inventors
- 👤 Richard Alexander Chapman
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-31 11:53
CPC Classifications
G; G03; G03F; G03F7/00; G03F7/004; G03F7/09; G03F7/091; H; H10; H10P; H10P76/00; G02; G02B; G02B1/00; G02B1/10; G02B1/11; G03F7/26; G03F7/40; H10D; H10D64/00; H10D64/01; H10D64/013; H10D64/01302; H10D64/01304; H10D64/01326; H10P50/00; H10P50/71; H10P76/20; H10P76/204; H10P76/2041; H10P76/2043
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
87 words
A method of lithography comprising; providing a first layer to be patterned; forming an intermediate layer over said first layer; forming a radiation sensitive layer overlying said intermediate layer; patterning said radiation sensitive layer with radiation; removing portions of said intermediate layer to form a first patterned region substantially underlying said radiation sensitive layer; removing portions of said first patterned region to form a second patterned region; and removing portions of said first layer using said second patterned region as at least a portion of a mask.
Claim 2
Dependent Claim
23 words
The method of claim 1, wherein said step of removing portions of said intermediate layer comprises removing exposed portions of said intermediate layer.
Claim 3
Dependent Claim
27 words
The method of Claim 1 or Claim 2 further comprising the steps of; forming said intermediate layer from TiN; and forming said radiation sensitive layer from photoresist.
Claim 4
Independent Claim
25 words
The method of any of Claims 1 to 3, wherein said step of removing portions of said first patterned region is performed by plasma etching.
Claim 5
Independent Claim
28 words
The method of any preceding claim further comprising the steps of; forming said first layer from polysilicon; and removing portions of said first layer by anisotropic plasma etching.
Claim 6
Independent Claim
42 words
The method of any preceding claim, wherein said step of forming said intermediate layer comprises the step of; forming a buried anti-reflective coating (BARC) layer on said first layer, said buried anti-reflective coating layer being absorptive of radiation of a first wavelength.
Claim 7
Dependent Claim
37 words
The method of Claim 6, wherein said step of forming a radiation sensitive layer comprises; forming a photoresist layer on said buried anti-reflective coating layer, said photoresist layer being exposed by radiation of the said first wavelength.
Claim 8
Dependent Claim
35 words
The method of Claim 7, wherein said step of patterning said radiation sensitive layer comprises; patterning said photoresist layer using radiation inclusive of said first wavelength to form said patterned region in said photoresist layer.
Claim 9
Dependent Claim
35 words
The method of Claim 8, wherein the step of patterning said photoresist layer comprises patterning said photoresist layer such that said first patterned region is formed in said photoresist layer having a minimum linewidth W.
Claim 10
Dependent Claim
39 words
The method of Claim 8 or Claim 9, wherein said step of removing portions of said intermediate layer comprises; etching said buried anti-reflective coating layer using said patterned photoresist layer to form a first patterned buried anti-reflective coating region.
Claim 11
Dependent Claim
21 words
The method of Claim 10, wherein said step of etching said buried anti-reflective coating layer comprises using an anisotropic etching technique.
Claim 12
Independent Claim
46 words
The method of any of Claims 8 to 11, wherein said step of removing portions of said first patterned region comprises; etching said first patterned buried anti-reflective coating layer to remove at least a portion of a surface of said first patterned buried anti-reflective coating layer.
Claim 13
Dependent Claim
21 words
The method of Claim 12, wherein said etching step comprises etching said first patterned anti-reflective coating layer using isotropic etching technique.
Claim 14
Dependent Claim
22 words
The method of Claim 12, wherein said etching step comprises etching said first patterned anti-reflective coating layer using an anisotropic etching technique.
Claim 15
Dependent Claim
45 words
The method of Claim 13 or Claim 14 wherein said etching step comprises etching said first patterned buried anti-reflective coating layer to remove an amount ΔW from a surface of said first patterned buried anti-reflective coating layer to form a second buried anti-reflective coating layer.
Claim 16
Dependent Claim
35 words
The method of Claim 15, wherein said etching step comprises etching said first patterned buried anti-reflective coating layer to form a second patterned anti-reflective coating layer having a minimum linewidth W-2ΔW on said first layer.
Claim 17
Dependent Claim
33 words
The method of Claim 15 or Claim 16 wherein said step of removing portions of said first layer comprises; etching said first layer using said second patterned anti-reflective coating layer as the mask.
Claim 18
Dependent Claim
48 words
The method of Claim 11 or Claim 12; wherein said step of etching said buried anti-reflective coating layer comprises etching said buried anti-reflective coating layer to form a first patterned buried anti-reflective coating layer having a minimum linewidth W in a region substantially underlying said patterned photoresist layer.
Claim 19
Dependent Claim
37 words
The method of Claim 12 or Claim 13; wherein said step of etching said first layer comprises etching said first layer using said patterned buried anti-reflective coating layer and patterned layer of photoresist as an etch mask.
Claim 20
Independent Claim
18 words
The method any of Claims 8 to 19 comprising the step of; stripping said patterned layer of photoresist.
Claim 21
Dependent Claim
37 words
The method of Claim 20 further comprising the step of; removing said patterned buried anti-reflective coating layer such that substantially all residue from said stripping step is lifted off with removal of said patterned anti-reflective coating layer.
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