Methods for forming epitaxial self-aligned calcium silicide contacts and structures
US5248633A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 30, 1991 |
| Grant date | Sep 28, 1993 |
| Priority date | — |
| Expiry date | Sep 30, 2011 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/76889
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
The present invention is a method of forming conductive structures comprising the steps of providing a silicon substrate having a first surface of atomically clean (111) silicon, forming an epitaxial CaF.sub.2 insulating layer on the first surface, the insulating layer having an exposed surface opposing the first surface, positioning a metallic mask on the exposed surface, irradiating a predetermined portion of the exposed surface so as to decompose the insulating layer beneath the predetermined portion to thereby form a workpiece having a metallic Ca layer on the first surface of the (111) silicon substrate, removing the mask, annealing the workpiece at a predetermined temperature so as to form an epitaxial CaSi.sub.2 conductive structure, wherein a plane coincident with the first surface bisects the conductive structure. According to one aspect of the invention, the energetic ion beam can be a beam of ionizing radiation. According to another aspect of the invention, the energetic beam can be energetic ion beam whereby both the conductive structure and an underlying impurity region in the substrate can be formed simultaneously.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.