Optical characterization of deep O implants in GaAs

Journal Article · Fri Apr 01 00:00:00 EST 1977 · J. Appl. Phys.; (United States)

DOI:https://doi.org/10.1063/1.323873· OSTI ID:7326456

Monemar, B; Blum, J M

Optical methods for characterization of deep implants in semiconductors are evaluated, notably optical absorption below band-gap energies, and photoluminescence. Results from such measurements on 2--3-MeV O implants in GaAs are presented, and discussed with emphasis on possible physical interpretations of defect properties. The spectral shape of optical absorption from doses < or =10/sup 14/ cm/sup -2/ indicates that a description of initial damage as amorphous regions is not appropriate. It seems possible to qualitatively explain this spectral behavior before anneal as mainly due to the electronic states caused by disrupted bonds along the ion track. Photoluminescence (PL) spectra of implanted material (before as well as after anneal) can give specific information on the various defect complexes created by the treatment. Furthermore, the intensity reduction of PL due to residual recombination centers is by far the most sensitive way of detecting residual damage in the material, and thus offers several applications for evaluation of, e.g., annealing efficiency or, for low doses, annealing during implantation. Such measurements also show that there is an apparent orientation dependence on the level of damage introduced, so that <110> is most favorable, while <100> and especially <111> orientation of the GaAs surface resulted in higher damage. A characteristic annealing temperature of 460 +- 30 degreeC for PL efficiency was found in n-type as well as p-type material, indicating annealing of important nonradiative recombination centers at this temperature. The ultimate result of annealing is critically dependent on the encapsulation technique, and we found that neither Al/sub 2/O/sub 3/ nor Si/sub 3/N/sub 4/ prepared by sputtering at 400 degreeC are satisfactory as capping material on n-GaAs, although they caused a slight reduction on the rate of Ga outdiffusion during anneal. Results from PL-profiling experiments are also discussed.

• Research Organization: IBM Thomas J. Watson Research Center, Yorktown Heights, New York 10598
• OSTI ID: 7326456
• Journal Information: J. Appl. Phys.; (United States), Vol. 48:4
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
GALLIUM ARSENIDES
PHYSICAL RADIATION EFFECTS
ALUMINIUM OXIDES
ANNEALING
CRYSTAL DEFECTS
DOPED MATERIALS
DOSE-RESPONSE RELATIONSHIPS
HEAT TREATMENTS
ION IMPLANTATION
OXYGEN IONS
PHOTOLUMINESCENCE
PROTECTIVE COATINGS
RECOMBINATION
SILICON NITRIDES
ALUMINIUM COMPOUNDS
ARSENIC COMPOUNDS
ARSENIDES
CHALCOGENIDES
CHARGED PARTICLES
COATINGS
CRYSTAL STRUCTURE
GALLIUM COMPOUNDS
IONS
LUMINESCENCE
NITRIDES
NITROGEN COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
PNICTIDES
RADIATION EFFECTS
SILICON COMPOUNDS
360605* - Materials- Radiation Effects