Process for making self-aligning thin film transistors
US4767723A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 30, 1987 |
| Grant date | Aug 30, 1988 |
| Priority date | — |
| Expiry date | Oct 30, 2007 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S438/928
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A process for making a self-aligned thin film transistor, said process comprising the steps of: (1) providing a gate which comprises a glass substrate, a transparent electrode on top thereof, and a metal electrode on top of said transparent electrode, (2) forming a stack by depositing over said gate a triple layer structure consisting of gate dielectric material, active material and a top passivating dielectric, (3) coating the top of said triple layer with a dual-tone photoresist, (4) exposing said photoresist from the top through a mask having transparent areas, opaque areas and areas transparent to selective wavelengths, using broad band UV light, (5) developing the photoresist by treatment with a solvent, (6) etching the stack with a liquid etchant through to the glass substrate, (7) exposing the photoresist from the bottom through the glass substrate using near UV light, (8) developing the photoresist with a solvent, and (9) etching off the top passivating layer of the stack.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.