Patent EP0368089A2 successfully refreshed from Google Patents.
EP0368089A2
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EP
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Method of manufacturing a mask for lithographic patterning
Assignee: Fujitsu Ltd
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Filing: 1989-10-27
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Granted: —
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Expires: 2009-10-27
Abstract
Abstract A mask for lithographic patterning comprises a base body (10) provided with a through hole (15, 25) passing from a top side to a bottom side thereof, a mask layer (11, 33) provided on the top side of the base body so as to close the through hole, the mask layer being defined by a substantially flat top surface (11₁) and a substantially flat bottom surface (11₂) and having a thickness ranging from about 2 µm to about 20 µm, and a plurality of patterned apertures (20 - 25) provided on the mask layer at a part closing the through hole.
Inventors
- 👤 Kiichi Sakamoto
- 👤 Hiroshi Yasuda
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 09:50
CPC Classifications
G; G03; G03F; G03F1/00; G03F1/20
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
103 words
A mask for lithographic patterning comprising a base body (10) provided with a through hole (15, 25) passing from a top side to a bottom side thereof, a mask layer (11, 33) provided on the top side of the base body so as to close the through hole, and a plurality of patterned apertures (20 - 25) provided on the mask layer in correspondence to the through hole, characterized in that said mask layer is defined by a substantially flat top surface (11₁) and a substantially flat bottom surface (11₂) and has a thickness ranging from about 2 µm to about 20 µm.
Claim 2
Dependent Claim
103 words
A mask for lithographic patterning comprising a base body (10) provided with a through hole (15, 25) passing from a top side to a bottom side thereof, a mask layer (11, 33) provided on the top side of the base body so as to close the through hole, and a plurality of patterned apertures (20 - 25) provided on the mask layer in correspondence to the through hole, characterized in that said mask layer is defined by a substantially flat top surface (11₁) and a substantially flat bottom surface (11₂) and has a thickness ranging from about 2 µm to about 20 µm.
Claim 3
Dependent Claim
26 words
A mask as claimed in claim 1 characterized in that said through hole (15, 25) has a size of at least about a few hundred microns.
Claim 4
Dependent Claim
24 words
A mask as claimed in claim 1 characterized in that said through hole (15, 25) has a size of at least about several millimeters.
Claim 5
Dependent Claim
24 words
A mask as claimed in claim 1 characterized in that said through hole (15, 25) has a size of about several tens of millimeters.
Claim 6
Dependent Claim
32 words
A mask as claimed in claim 1 characterized in that each of said plurality of patterned apertures (20 - 25) has a size of at least about 300 µm X 300 µm.
Claim 7
Dependent Claim
24 words
A mask as claimed in claim 1 characterized in that said base body (10) comprises a glass and said mask layer (11) comprises silicon.
Claim 8
Dependent Claim
33 words
A mask as claimed in claim 1 characterized in that said base body (10) comprises a silicon body (31) covered by a silicon oxide layer (32) and said mask layer (33) comprises silicon.
Claim 9
Dependent Claim
22 words
A mask as claimed in claim 1 characterized in that said mask layer (33) is further covered by a metal layer (40).
Claim 10
Dependent Claim
16 words
A mask as claimed in claim 8 characterized in that said metal layer (40) comprises tantalum.
Claim 11
Independent Claim
138 words
A method of manufacturing a mask for lithographic patterning, characterized by steps of connecting a silicon substrate (11, 33) on a top side of a base body (10), said base body having a silicon oxide layer (32) at least on said top side, reducing a thickness of the silicon substrate connected to the base body such that the silicon substrate has a reduced thickness which is smaller than about 20 um but larger than about 2 um, patterning the silicon substrate to form a mask pattern region (12, 34) in the silicon substrate such that a plurality of mask patterns (20 - 25) are provided in the mask pattern region in a form of apertures, and etching the base body such that a part (15, 25) of the base body located under the mask pattern region is removed.
Claim 12
Independent Claim
138 words
A method of manufacturing a mask for lithographic patterning, characterized by steps of connecting a silicon substrate (11, 33) on a top side of a base body (10), said base body having a silicon oxide layer (32) at least on said top side, reducing a thickness of the silicon substrate connected to the base body such that the silicon substrate has a reduced thickness which is smaller than about 20 um but larger than about 2 um, patterning the silicon substrate to form a mask pattern region (12, 34) in the silicon substrate such that a plurality of mask patterns (20 - 25) are provided in the mask pattern region in a form of apertures, and etching the base body such that a part (15, 25) of the base body located under the mask pattern region is removed.
Claim 13
Dependent Claim
24 words
A method as claimed in claim 10 characterized in that said step of reducing the thickness comprises lapping of the silicon substrate (11, 33).
Claim 14
Dependent Claim
29 words
A method as claimed in claim 10 characterized in that each of said mask patterns (12, 34) has a size of at least about 300 µm X 300 µm.
Claim 15
Dependent Claim
64 words
A method as claimed in claim 10 characterized in that said step of connecting the silicon substrate (11, 33) on the top side of the base body (10) comprises a step of annealing the silicon substrate and the base body at a temperature between 900 °C and 1000 °C in a state that the silicon substrate and the base body are contacted each other.
Claim 16
Dependent Claim
37 words
A method as claimed in claim 10 characterized in that said base body (10) comprises a glass containing silicon oxide and said step of etching comprising a step of isotropic etching process using a fluoride etching agent.
Claim 17
Dependent Claim
56 words
A method as claimed in claim 10 characterized in that said base body (10) comprises a silicon body (31) carrying the silicon oxide layer (32) and said step of connecting the silicon substrate further comprises a step of providing the silicon oxide layer on the top side of the base body by thermal oxidation of silicon.
Claim 18
Dependent Claim
44 words
A method as claimed in claim 15 characterized in that said step of etching comprises an anisotropic etching of the silicon body (31) using a solution of potassium hydrooxide and an isotropic etching of the silicon oxide layer (32) by a fluoride etching agent.
Claim 19
Dependent Claim
32 words
A method as claimed in claim 10 characterized in that the method further comprises a step of depositing a metal layer (40) on the silicon substrate (33) after the step of patterning.
References Cited (Backward Citations)
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