摘要 |
Disclosed is a process for forming a planarized multilevel ship wiring structure. Starting from a substrate having thereon at least a metal stud serving as vertical wiring between two levels of metallization, a quartz layer is deposited, obtaining a non-planar structure. A thick planarizing photoactive photoresist is applied. The photoresist is converted by silylation process into a silicate having substantially the same etch rate as that of quartz. Silylation is accomplished by, for example, subjecting the resist to a bath of hexamethyldisilazane, hexamethylcyclotrisilazene, octamethylcyclotetrasilazane, N,N,dimethylaminotrimethylsilane or N,N,diethylaminotrimethylsilane, for a period of time determined by the thickness of the resist. Unwanted portions of the silylated resist and quartz are etched back at 1:1 etch rate ratio to the level of the stud.
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