Radiation imagery chemistry: process – composition – or product th – Radiation modifying product or process of making – Radiation mask
Patent
1992-01-16
1993-09-07
McCamish, Marion E.
Radiation imagery chemistry: process, composition, or product th
Radiation modifying product or process of making
Radiation mask
378 35, 36447424, G03F 900
Patent
active
052427706
ABSTRACT:
An improvement for reducing proximity effects comprised of additional lines, referred to as intensity leveling bars, into the mask pattern. The leveling bars perform the function of adjusting the edge intensity gradients of isolated edges in the mask pattern, to match the edge intensity gradients of densely packed edges. Leveling bars are placed parallel to isolated edges such that intensity gradient leveling occurs on all isolated edges of the mask pattern. In addition, the leveling bars are designed to have a width significantly less than the resolution of the exposure tool. Therefore, leveling bars that are present in the mask pattern produce resist patterns that completely developed away when a nominal exposure energy is utilized during exposure of photoresist.
REFERENCES:
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Chen Jang F.
Matthews James A.
Chapman Mark A.
McCamish Marion E.
MicroUnity Systems Engineering, Inc.
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