06979518 cites 2 patents.

An attenuating embedded phase shift photomask blank that produces a phase shift of the transmitted light is formed with an optically translucent film made of metal, silicon, nitrogen and oxygen. An etch stop layer is added to improve the etch selectivity of the phase shifting layer. A wide range of optical transmission (0.001% up to 15% at 157 nm) is obtained by this process.

Title
Attenuated embedded phase shift photomask blanks
Application Number
10/727925
Publication Number
6979518 (B2)
Application Date
December 4, 2003
Publication Date
December 27, 2005
Inventor
Kenneth Christopher Racette
Fairfax
VT, US
Arpan Pravin Mahorowala
Bronxville
NY, US
Robert N Lang
Pleasant Valley
NY, US
Michael Straight Hibbs
Westford
VT, US
S Jay Chey
Ossining
NY, US
Katherina Babich
Chappaqua
NY, US
Marie Angelopoulos
Cortlandt Manor
NY, US
Agent
Daniel P Morris Esq
Scully Scott Murphy & Presser
Assignee
International Business Machines Corporation
NY, US
IPC
G03F 009/00
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