Optical characterization of deep O implants in GaAs

Journal Article · Fri Apr 01 04:00:00 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), Journal Name: J. Appl. Phys.; (United States) Vol. 48:4; ISSN JAPIA
• Country of Publication: United States
• Language: English

Related Subjects

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