Method using laser irradiation for the production of atomically clean crystalline silicon and germanium surfaces
Abstract
This invention relates to a new method for removing surface impurities from crystalline silicon or germanium articles, such as off-the-shelf p- or n-type wafers to be doped for use as junction devices. The principal contaminants on such wafers are oxygen and carbon. The new method comprises laser-irradiating the contaminated surface in a non-reactive atmosphere, using one or more of Q-switched laser pulses whose parameters are selected to effect melting of the surface without substantial vaporization thereof. In a typical application, a plurality of pulses is used to convert a surface region of an off-the-shelf silicon wafer to an atomically clean region. This can be accomplished in a system at a pressure below 10-/sup 8/ Torr, using Q-switched ruber-laser pulses having an energy density in the range of from about 60 to 190 MW/cm/sup 2/.
- Inventors:
- Issue Date:
- OSTI Identifier:
- 5068798
- Assignee:
- TIC; ERA-05-035145; EDB-80-106852
- DOE Contract Number:
- W-7405-ENG-26
- Resource Type:
- Patent
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 36 MATERIALS SCIENCE; GERMANIUM; SURFACES; SILICON; CLEANING; CARBON; LASER RADIATION; MELTING; OXYGEN; CRYOGENIC FLUIDS; ELECTROMAGNETIC RADIATION; ELEMENTS; FLUIDS; METALS; NONMETALS; PHASE TRANSFORMATIONS; RADIATIONS; SEMIMETALS; 360101* - Metals & Alloys- Preparation & Fabrication
Citation Formats
Ownby, G W, White, C W, and Zehner, D M. Method using laser irradiation for the production of atomically clean crystalline silicon and germanium surfaces. United States: N. p., 1979.
Web.
Ownby, G W, White, C W, & Zehner, D M. Method using laser irradiation for the production of atomically clean crystalline silicon and germanium surfaces. United States.
Ownby, G W, White, C W, and Zehner, D M. Fri .
"Method using laser irradiation for the production of atomically clean crystalline silicon and germanium surfaces". United States.
@article{osti_5068798,
title = {Method using laser irradiation for the production of atomically clean crystalline silicon and germanium surfaces},
author = {Ownby, G W and White, C W and Zehner, D M},
abstractNote = {This invention relates to a new method for removing surface impurities from crystalline silicon or germanium articles, such as off-the-shelf p- or n-type wafers to be doped for use as junction devices. The principal contaminants on such wafers are oxygen and carbon. The new method comprises laser-irradiating the contaminated surface in a non-reactive atmosphere, using one or more of Q-switched laser pulses whose parameters are selected to effect melting of the surface without substantial vaporization thereof. In a typical application, a plurality of pulses is used to convert a surface region of an off-the-shelf silicon wafer to an atomically clean region. This can be accomplished in a system at a pressure below 10-/sup 8/ Torr, using Q-switched ruber-laser pulses having an energy density in the range of from about 60 to 190 MW/cm/sup 2/.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Fri Dec 28 00:00:00 EST 1979},
month = {Fri Dec 28 00:00:00 EST 1979}
}