Technical Issues in Infrared Detectors and Arrays, 1983
The chemistry of the anodic oxide of Hg(1-x)Cd(x)Te is reviewed. The oxide is generally believed ... more The chemistry of the anodic oxide of Hg(1-x)Cd(x)Te is reviewed. The oxide is generally believed to contain little Hg and primarily consist of CdTeO3 with smaller amounts of HgTeO3, CdTe2O5, HgTe2O5, or TeO2. Consistent with the weakening Hg-Te bond strength for lower x value material, a severely defective interface between the oxide and the substrate is reported for Hg0.8Cd0.2Te, but
Lockheed Martin Sanders' Integrated Optoelectronics Group makes flexible smart-pixel devices ... more Lockheed Martin Sanders' Integrated Optoelectronics Group makes flexible smart-pixel devices for a variety of applications. The devices combine GaAs pin heterostructure materials in a Fabry-Perot cavity with CMOS circuitry, and are capable of operation as modulators, ...
A vertical-cavity surface-emitting laser based bidirectional free-space optical interconnect has ... more A vertical-cavity surface-emitting laser based bidirectional free-space optical interconnect has been implemented to interconnect two printed circuit boards. A total of 512 clustered channels with a density of 2844 channels/cm2 are transmitted over a distance of 83 mm. The optical interconnect is a combination of refractive microlenses and diffractive minilens relays.
Ternary GaAs1-ySby and quaternary Al0.5Ga0.5As1-ySby compositionally step-graded buffer structure... more Ternary GaAs1-ySby and quaternary Al0.5Ga0.5As1-ySby compositionally step-graded buffer structures graded to a 4.6% mismatch on GaAs were evaluated by transmission electron microscopy. Cross-sectional bright field imaging (g=004) revealed the presence of compositional modulations parallel to the (001) interface with a period of 1-2 nm that were used to establish the morphology of the growth surface during buffer layer deposition. Analysis of the Sb-graded ternary structures shows that the growth surface remained planar with a maximum peak-to-valley height of 4.4+/-0.6 nm located near the topmost layer. A threading dislocation density of 108-109 cm-2 was measured in both types of buffer layers and an improvement in peak-to-valley amplitude (2.3+/-0.5 nm vs 4.4+/-0.6 nm) was observed in the Al-containing quaternary alloys.
Technical Issues in Infrared Detectors and Arrays, 1983
The chemistry of the anodic oxide of Hg(1-x)Cd(x)Te is reviewed. The oxide is generally believed ... more The chemistry of the anodic oxide of Hg(1-x)Cd(x)Te is reviewed. The oxide is generally believed to contain little Hg and primarily consist of CdTeO3 with smaller amounts of HgTeO3, CdTe2O5, HgTe2O5, or TeO2. Consistent with the weakening Hg-Te bond strength for lower x value material, a severely defective interface between the oxide and the substrate is reported for Hg0.8Cd0.2Te, but
Lockheed Martin Sanders' Integrated Optoelectronics Group makes flexible smart-pixel devices ... more Lockheed Martin Sanders' Integrated Optoelectronics Group makes flexible smart-pixel devices for a variety of applications. The devices combine GaAs pin heterostructure materials in a Fabry-Perot cavity with CMOS circuitry, and are capable of operation as modulators, ...
A vertical-cavity surface-emitting laser based bidirectional free-space optical interconnect has ... more A vertical-cavity surface-emitting laser based bidirectional free-space optical interconnect has been implemented to interconnect two printed circuit boards. A total of 512 clustered channels with a density of 2844 channels/cm2 are transmitted over a distance of 83 mm. The optical interconnect is a combination of refractive microlenses and diffractive minilens relays.
Ternary GaAs1-ySby and quaternary Al0.5Ga0.5As1-ySby compositionally step-graded buffer structure... more Ternary GaAs1-ySby and quaternary Al0.5Ga0.5As1-ySby compositionally step-graded buffer structures graded to a 4.6% mismatch on GaAs were evaluated by transmission electron microscopy. Cross-sectional bright field imaging (g=004) revealed the presence of compositional modulations parallel to the (001) interface with a period of 1-2 nm that were used to establish the morphology of the growth surface during buffer layer deposition. Analysis of the Sb-graded ternary structures shows that the growth surface remained planar with a maximum peak-to-valley height of 4.4+/-0.6 nm located near the topmost layer. A threading dislocation density of 108-109 cm-2 was measured in both types of buffer layers and an improvement in peak-to-valley amplitude (2.3+/-0.5 nm vs 4.4+/-0.6 nm) was observed in the Al-containing quaternary alloys.
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