摘要 |
In manufacture of VLSI semiconductor devices, the insulator surface upon which a metallization pattern is deposited must be smooth to facilitate lithographic operations. This requires the insulator to be thick and flowed or otherwise treated to eliminate steep edges. A contact hole etched in a thick insulator has steep sidewalls, however, and so chemical vapor deposition is preferrably used for the metallization so the sidewalls will be coated. A thin insulator coating is deposited after the contact holes are etched and prior to metallization to cover the low-resistance flowed insulator and self-align the contacts.
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