No abstract

Mid-infrared (3-5 pm) lasers and LEDs are Wig developed for use in chemical sensor systems. As-rich, InAsSb heterostructures display unique electronic properties that are beneficial to the performance of these midwave infrared emitters. The metal-organic chemical vapor deposition (MOCVD) growth of AIAs,,Sb, cladding layers and InAsSb/InAsP superlattice active regions are described. A regrowth technique has been used to fabricate gain-guided, injection lasers using undoped @-type) AIAso.,,Sbo, for optical confinement In device studies, we demonstrate lasers and LEDs utilizing the semi-metal properties of a p-GaAsSb/n-InAs heterojunction as a source for injection of electrons into the active region of emitters. This avoids the difficulties associated with n-type doping of AlAsSb cladding layers required for conventional p-n junction lasers and also provides a means for construction of active regions with multiple gain stages. Gain guided injected lasers employing a strained InAsSb/InAs multiquantum well active region operated up to 210 K in pulsed mode, with an emission wavelength of 3.8-3.9 p. A characteristic temperature of 40 K was observed to 140 K and 29 K from 140 K to 210 K. An optically pumped laser with an InAsSb/InAsP superlattice active region is also described. The maximum operating temperature of this 3.7 pm laser was 240 K.

No abstract

Cells and ElectricalConduction of Pure and Doped A120J," J . .4m. Ceram. Soc., 54 [9] 444-5 I ( I 97 I ) .

Gläser und Glaskeramiken (β‐Eukryptit) mit Zusammensetzungen nahe der von stöchiometrischem L120°C A1203°C 2 SiO2, z.B. LiAlSiO4 , sind, wie aus Messungen der Ionenleitfähigkeit (25‐650°C) hervorgeht, bei hohen Temperaturen gute Litleitende Festelektrolyte (bei N 600°C etwa l0" (ohm′ cm)" ).

AlSb and AlAsxSb1−x epitaxial films grown by metalorganic chemical vapor deposition were successfully doped p- or n-type using diethylzinc or tetraethyltin, respectively. AlSb films were grown at 500 ° C and 76 Torr using trimethylamine alane and triethylantimony. AlAs0.16Sb0.84 films lattice matched to InAs were grown at 600 ° C and 76 Torr by adding arsine. Secondary ion mass spectroscopy showed C and O levels below 2×1018 and 6×1018 cm−3, respectively, for undoped AlSb. Similar levels of O were found in AlAs0.16Sb0.84 films but C levels were an order of magnitude less in undoped and Sn-doped AlAs0.16Sb0.84 films. Hall measurements of AlAs0.16Sb0.84 showed hole concentrations between 1×1017 to 5×1018 cm−3 for Zn-doped material and electron concentrations in the low to mid- 1018 cm−3 for Sn-doped material.

No abstract

We report in-situ optical reflectance monitoring during the metalorganic chemical vapor deposition (MOCVD) growth of (Al)GaN. In addition to the well-known thin film interference effect which enables a real-time determination of growth rate, we show that several insights about the MOCVD growth process can be gained by using this simple yet powerful technique. Illustrations from a variety of applications for in-situ reflectance monitoring, specifically the study of growth evolution, the control of alloy fractions, and the use of growth rate to gauge surface kinetics and gas injection will be reported.