Chemical composition of anodic oxides grown on lightly doped ptype InP have been investigated by XPS. Anodization was performed in the constant current density (J,) mode using an ortho-phosphoric acid solution mixed with acetonitrile (ACN). The electrolyte was chosen after experimentation on the effect of the anudiition parameters (electrolyte, viscosity of the electrolyte and pH, J, and illumination level) and annealing conditions on the uniformity and stability of the oxide and the contamination level, as determined by SEMPDAX, SIMS and XPS. Based on our XPS investigation, it appears that the inhomogeneity with depth of the anudii oxides grown on ptype InP is strongly dependent on the growth conditions. Depending on the anodization procedure, the anodic oxide In recent years, indium phosphide has proved to be a very promising semiconductor material for various applications owing to its intrinsic properties, such as high electron mobility and high radiation tolerance. Hence, major attention is beginning to be devoted to InP owing to its potential applications, such as highspeed electronic and integrated opto-electronic devices and high-performance radiation-resistant space solar cells. All these applications are not yet technologically mature and more studies are needed before highperformance devices can be realized.One of the major problems yet to be solved in InP technology is to form insulators on the InP surface that have good chemical stability and dielectric and interface properties. Such insulators are needed in applications requiring surface passivation and for selective etching during device fabrication. Surface passivation is obtained by growth of an insulating layer (extrinsic passivation), which compensates the surface states so that the surface recombination velocity (SRV) is greatly reduced.Based on previously reported information on the insulators formed on InP (e.g. as gate insulators for MISFETS),'-3 the ideal insulator for surface passivation and selective etching should have the following bulk and interfacial properties:

No abstract

No abstract

No abstract

This experimental study evaluates the potential of a cesium plasma as an emitter for a thermophotovoltaic (TPV) energy conversion system. A cesium plasma, as a result of the ground-state transitions of its single outer-shell electron, produces large amounts of radiation in the 850–890-nm wavelength region. This would provide excellent coupling to silicon, gallium arsenide, and indium phosphide photovoltaic cells. Measurements of the radiative efficiency, the sum of the power at the 852 and 894 nm wavelengths relative to the total emitted power were made and correlated to the plasma operating variables. It was determined that for atomic density in the range (3–6)×1021/m3 and electron temperature in the range 2000–3000 K, radiative efficiencies in excess of 70% are attainable. This would indicate that a cesium plasma with its selective emission characteristics and low electron operating temperatures of 2000–3000 K would be an excellent candidate as an emitter in a TPV system.