Radiation imagery chemistry: process – composition – or product th – Including control feature responsive to a test or measurement
Patent
1995-06-29
1996-09-17
Duda, Kathleen
Radiation imagery chemistry: process, composition, or product th
Including control feature responsive to a test or measurement
430311, 430396, G03F 720
Patent
active
055567266
ABSTRACT:
A method of determining quantitatively the exposure levels for photoresists in semiconductor photolithography employs a specially designed grating pattern on a mask. The mask is first used to expose a series of LIM image gratings of different dosages. Then a normal plane wave at a longer wavelength is incident on these gratings one by one, and some nonzero order diffraction efficiency of the grating is measured to determine quantitatively the correct dosage to be used. This method can make a determination of exposure dosage, without knowledge of underlying film thickness and refractive index, and handle either resist thickness change or underlying film thickness/refractive index change or both.
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Duda Kathleen
International Business Machines - Corporation
Soucar, Esq. Steven J.
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