Accession Number:

ADA210224

Title:

Effects of Coherent Scattering on Infrared Absorption in Doped Semiconductors

Descriptive Note:

Final rept. Jun 1985-Aug 1986

Corporate Author:

AIR FORCE WRIGHT AERONAUTICAL LABS WRIGHT-PATTERSON AFB OH MATERIALS LAB

Personal Author(s):

• Grigsby, Peggy J.
• Brown, Gail J.

Report Date:

1989-04-01

Pagination or Media Count:

39.0

Abstract:

An improved theoretical model was developed for interpreting the infrared absorption spectra of doped semiconductors. The model focused on the specific problem of coherent scattering effects or optical channeling. These effects are produced by coherent multiple internal reflections from the polished plane-parallel faces of an optically thin sample. The coherent scattering produces oscillating noise on the infrared absorption spectrum. This noise makes it difficult to determine the correct absorption coefficient from the spectrum. The effect occurs in both silicon and gallium arsenide. The specific expression for the transmittance in the presence of scattering was determined and the inversion of this relation was calculated to obtain the absorption coefficient. In cases where the equation based on coherent scattering did not give results, a combination of coherent and incoherent scattering equations was used to minimize the channeling oscillations.

Descriptors:

• *COHERENT SCATTERING
• *INFRARED SPECTRA
• *GALLIUM ARSENIDES
• *ABSORPTION SPECTRA
• *INCOHERENT SCATTERING
• *SILICON
• ABSORPTION
• EQUATIONS
• INFRARED RADIATION
• OSCILLATION
• ABSORPTION COEFFICIENTS
• NOISE
• TRANSMITTANCE
• COHERENCE
• THEORY
• INTERNAL REFLECTION
• SCATTERING
• MODELS

Subject Categories:

• Atomic and Molecular Physics and Spectroscopy
• Optics
• Solid State Physics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE