Browse Prior Art Database

Thermal Homogenized Boron Source Powders

IP.com Disclosure Number: IPCOM000075320D
Original Publication Date: 1971-Sep-01
Included in the Prior Art Database: 2005-Feb-24
Document File: 1 page(s) / 11K

Publishing Venue

IBM

Related People

DeFries, RM: AUTHOR

Abstract

Single crystal blending of opposite ends of a within-spec boron source crystal (although mechanically homogenized) is characterized by in-diffusion and out-diffusion mechanics (prior to the uniform deposition) as the source particles reach the level of thermal equilibrium. These characteristics were evidenced when deposition times and temperatures were changed three minutes with no change in sheet resistance, while changes of five minutes gave drastic resistance value changes.

This text was extracted from a PDF file.
This is the abbreviated version, containing approximately 100% of the total text.

Page 1 of 1

Thermal Homogenized Boron Source Powders

Single crystal blending of opposite ends of a within-spec boron source crystal (although mechanically homogenized) is characterized by in-diffusion and out-diffusion mechanics (prior to the uniform deposition) as the source particles reach the level of thermal equilibrium. These characteristics were evidenced when deposition times and temperatures were changed three minutes with no change in sheet resistance, while changes of five minutes gave drastic resistance value changes.

It appears that freeze-out sources (bulk silicon charge + elemental boron) might have elemental boron still not compounded with the silicon after source powder preparation.

It was found that both freeze-out and single crystal blends, of boron source powders, can yield more consistent repetitive results if they are thermally homogenized at operating temperatures and times prior to a live run. Normally, the boron surface concentration (in the desired ranges) can be thermally homogenized in an evacuated capsule at operating temperatures and times which will not only provide the same surface concentrations, but will also be characterized with a smaller sigma ohms per square centimeter. Such thermally homogenized boron source powders can be stored indefinitely within clean vacuum chambers.

1