Integrated circuit with twin tub
US6017787A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 31, 1996 |
| Grant date | Jan 25, 2000 |
| Priority date | — |
| Expiry date | Dec 31, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D84/038
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A twin tub integrated circuit and method for its formation are disclosed. A portion of the substrate is covered by photoresist while an n region is formed, illustratively, by ion implantation. Then the n region is covered with a protective material, illustratively a spin on glass or another photoresist. The previously-formed photoresist is removed and a p-type implant is performed to create an p region. When all the protective layers are removed, both regions have upper surfaces which are co-planar. The co-planar surfaces, a departure from previous practice, make submicron lithography easier. The regions are annealed to form twin tubs.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.