Raman-scattering studies of the structure of ion-implanted GaAs

Thesis/Dissertation · Thu Jan 01 04:00:00 EST 1987

OSTI ID:7200966

Holtz, M W

Extensive Raman-scattering studies were performed in order to study the structure of ion-implanted GaAs, prior to any anneal. The spectroscopic evidence is consistent with a fine-scale mixture of amorphous and microcrystalline GaAs. Excessive bombardment with 120-keV SiF/sub 3//sup +/ ions results in a 500-A thick surface layer which is completely amorphous (a-GaAs). A detailed chemical-etch damage depth profile was completed for 45-keV Be/sup +/-implanted GaAs, which is not completely amorphized. The damage is characterized using the microcrystalline longitudinal-optical (LO) phonon frequency, line width, and intensity, and the intensity of the a-GaAs component of the Raman spectrum. The damage layer possesses a 1500-A thick surface layer of constant, high damage. This high-damage plateau is followed by a transition region in which the damage level smoothly decreases until the undisturbed crystal is reached near 4000 A. LO intensities were analyzed, within the amorphous/crystalline mixed-phase model, to obtain the volume fractions of the two components. Consistent estimates of the optical absorption in the high-damage plateau were obtained via two independent means.

• Research Organization: Virginia Polytechnic Inst. and State Univ., Blacksburg (USA)
• OSTI ID: 7200966
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360605* -- Materials-- Radiation Effects
AMORPHOUS STATE
ARSENIC COMPOUNDS
ARSENIDES
CATIONS
CHARGED PARTICLES
DAMAGE
ENERGY RANGE
FLUORIDES
FLUORINE COMPOUNDS
GALLIUM ARSENIDES
GALLIUM COMPOUNDS
HALIDES
HALOGEN COMPOUNDS
ION IMPLANTATION
IONS
KEV RANGE
KEV RANGE 100-1000
LAYERS
PNICTIDES
RAMAN EFFECT
SILICON COMPOUNDS
SILICON FLUORIDES
SURFACES