RF Vacuum Microelectronics
Abstract
Since this is the first quarterly progress report, a brief review will be given of the basic Hughes process as developed up through 1990 to create FEAs. Uniform pyramidal tips are defined when a <100> Si substrate is etched through a Si3N4 mask using KOH. The width of the opening determines the depth of this self-limiting etch. The result is a crystallographically sharp pyramidal hole formed by the 111 planes. Any desired array pattern of these holes can be formed. These holes are subsequently thermally oxidized to produce a thin oxide etch barrier, and this etched Si wafer then becomes a 'mold' or negative of the desired array of tips. Polysilicon is deposited into the mold and built up to a self-supporting thickness. The mold is then etched away leaving a array of uniform polysilicon tips on a self-supporting polysilicon substrate.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 30, 1992
- Accession Number
- ADA255019
Entities
Organizations
- Hughes Aircraft Company