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US5221429A Expired / Lapsed US ⏱️ 0.0 years remaining

Method of manufacturing phase-shifted diffraction grating

Assignee: Toshiba Corp
•
Filing: 1991-04-17
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Granted: 1993-06-22
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Expires: 2011-04-17
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Abstract

Abstract A photoresist 12 is coated on a substrate 11, and a phase shift medium 13 is formed on the photoresist 12. The phase shift medium 13 is patterned. Thereafter, first and second laser beams 16 and 17 having asymmetric incidence angles with respect to the substrate 11 are radiated on the photoresist 12 to perform an interference exposing operation. The photoresist 12 is developed and post-baked, and the substrate 11 is etched using the photoresist 12 as a mask, thereby forming a diffraction grating having a discontinuous phase portion.

Inventors

  • 👤 Akio Makuta

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 19:32
CPC Classifications
H; H10; H10P; H10P50/00; H10P50/69; H10P50/691; H10P50/692; G; G02; G02B; G02B6/00; G02B6/10; G02B6/12; G02B6/122; G02B6/124; G03; G03F; G03F7/00; G03F7/0005; G03F7/001; H10P50/693; H10P50/695; H01; H01S; H01S5/00; H01S5/10; H01S5/12; H01S5/1231; H01S5/124

Claims Analysis

Total Claims: 5
Claim 1
Independent Claim 87 words
A method of manufacturing a phase-shifted diffraction grating characterized by comprising the steps of: coating a photoresist on a substrate; forming a phase shift medium on said photoresist; patterning said phase shift medium; radiating first and second laser beams having asymmetric incidence angles with respect to said substrate on said photoresist to perform an interference exposing operation; removing said phase shift medium; developing and post-baking said photoresist; and etching said substrate using said photoresist as a mask to form a diffraction grating having a discontinuous phase portion.
Claim 2
Independent Claim 87 words
A method of manufacturing a phase-shifted diffraction grating characterized by comprising the steps of: coating a photoresist on a substrate; forming a phase shift medium on said photoresist; patterning said phase shift medium; radiating first and second laser beams having asymmetric incidence angles with respect to said substrate on said photoresist to perform an interference exposing operation; removing said phase shift medium; developing and post-baking said photoresist; and etching said substrate using said photoresist as a mask to form a diffraction grating having a discontinuous phase portion.
Claim 3
Dependent Claim 24 words
A method of manufacturing a phase-shifted diffraction grating according to claim 1, characterized in that said phase shift medium is an SiO 2 film.
Claim 4
Dependent Claim 37 words
A method of manufacturing a phase-shifted diffraction grating according to claim 1, characterized in that said phase shift medium is patterned such that an end portion of said phase shift medium is located at a phase-shifted portion.
Claim 5
Dependent Claim 25 words
A method of manufacturing a phase-shifted diffraction grating according to claim 1, characterized in that said substrate is etched by an etchant containing hydrogen bromide.

References Cited (Backward Citations)

JPS61246701A Cited
JPS6370475A Cited
US4895790A Cited
US4988404A Cited
US5024726A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1996-06-21 1996-12-21 1997-06-22 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2000-06-21 2000-12-21 2001-06-22 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2004-06-21 2004-12-21 2005-06-22 $7700.00 Window Closed / Lapsed

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