Showing papers on "Antimonide published in 1989"

GaAs/GaSb strained‐layer heterostructures deposited by metalorganic vapor phase epitaxy

Abstract: The growth of strained GaSb/GaAs quantum wells has been attempted for the first time (7% lattice mismatch), with the antimonide layers being constrained to take on the GaAs lattice parameter in the interface plane. The critical thickness for pseudomorphic growth of the strained layer was about 15 A, with further growth resulting in islands of GaSb crystallites over the wafer surface. Photoluminescence spectra and photoconductivity from both single and double wells showed a strong signal at approximately 1.3 eV, identified as a Γ point transition. This was not consistent with band structure calculations for a GaSb/GaAs well, suggesting an error in the estimation of the band offsets and/or As incorporation in the strained layer.

Quantum-effect semiconductor devices

Abstract: A novel combination of semiconductor heterojunctions provide a quantum-effect device with resonant or enhanced transmission of electrons (or holes) due to tunneling into a quantum well state in the valence (or conduction) band. A particular heterostructure comprising sequentially grown layers of indium arsenide, aluminum antimonide, gallium antimonide, aluminum antimonide and indium arsenide, permits electrons tunneling from the indium arsenide conduction band through the aluminum antimonide barrier into a sub-band level in the valence band quantum well of the gallium antimonide. This particular embodiment produced a current-voltage characteristic with negative differential resistance and a peak-to-valley current ratio of about 20 at room temperature and 88 at liquid nitrogen temperature. The present invention can be used either as a two-contact device such as a diode or a three-contact device such as a transistor.

Reflection high-energy electron diffraction oscillations during molecular-beam epitaxy growth of gallium antimonide, aluminum antimonide, and indium arsenide

Abstract: We report the observation of reflection high‐energy electron diffraction (RHEED) intensity oscillations during the molecular‐beam epitaxy growth of gallium antimonide (GaSb), aluminum antimonide (AlSb), and indium arsenide (InAs). For GaSb, these oscillations were not observed at the normal substrate temperature used for growth of these compounds (500–550 °C), but only at lower temperatures. For continuous growth of AlSb at lower temperatures, the RHEED oscillations persist for ∼40 monolayers. For AlSb and GaSb, the recovery of RHEED oscillation amplitude after growth interruption is quite different from the recovery, if any, of specular spot intensity. The RHEED oscillations for AlSb were observed at 570 °C after growth of as little as 350 A of AlSb, which was nucleated directly on a GaAs substrate. Oscillations were seen in spite of the large lattice mismatch (7% with GaAs) and the large number of dislocations present (>109 cm−2). We have studied the effects of varying growth rates and flux ratios. The ...

Ga 0.96 Al 0.04 Sb Implanted Avalanche Photodiode; Perspective for a 2.55 μm SAM APD Photodetector

Abstract: Be+ implantation into Liquid Phase Epitaxial n Ga 0.96 Al 0.004 Sb has been used in order to study the photodetection characteristics of the resulting p+/n diode, in the multiplication region. The great difference observed between the multiplication in the respective cases of pure electron and hole photoinjections confirms that the room temperature ionization coefficients ratio is very different from unity making this material very promising for an antimonide based Separated Absorption Multiplication Avalanche Photodiode. (SAM APD).