Stepper process for VLSI circuit manufacture utilizing radiation absorbing dyestuff for registration of alignment markers and reticle
US4677043A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 1, 1985 |
| Grant date | Jun 30, 1987 |
| Priority date | — |
| Expiry date | Nov 1, 2005 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F9/00
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
The step-on-wafer process, also known as the step-and-repeat alignment process, for the production of very large scale integration (VLSI) microcircuitry with multi-layer interconnects, is greatly facilitated by incorporating, into at least the first layer of photoresist, a dyestuff which meets certain criteria the chief of which is that it be transparent to radiation to which the photoresist system is sensitive and that it absorb radiation of a wavelength to which the photoresist system is not sensitive. The use of photoresist systems in association with such dyestuffs has additional advantages. For example, the thickness of the photoresist layer deposited on a substrate can be checked prior to imaging without activating the photoresist.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.