Journal of The Electrochemical Society · 1990 · 24 citations · 0 references
EngineeringMaterials EngineeringMaterials ScienceElectronic MaterialsOptoelectronicsSemiconductor MaterialsDopingLuminescent MaterialsOptical Properties Of SemiconductorsOptoelectronic DevicesOptoelectronic MaterialsSemiconductor Crystal GrowthAnnealingAnnealing EffectsAnnealing Temperature EffectsCarrier ConcentrationCarrier Concentration ControlElectrical PropertiesPhotoluminescencePhotoluminescence Spectroscopy
Undoped single crystals grown by the LEC technique have been annealed at temperatures between 520°–820°C for 5h and their electrical properties and the photoluminescence spectra have been evaluated. It was found that the carrier concentration can be decreased up to by annealing at 620°C and the photoluminescence spectra are largely changed by annealing. When the annealing temperature is increased to higher than 720°C, the free exciton peak appears very prominently and many peaks appear at the longer wavelength region between 900 and 980 nm.