Low-frequency noises (LFN) and noise-like oscillations (NLO) in GaAs metal semiconductor field effect transistor (MESFET) channel current were investigated under sidegating bias conditions.It was found that the fluctu...Low-frequency noises (LFN) and noise-like oscillations (NLO) in GaAs metal semiconductor field effect transistor (MESFET) channel current were investigated under sidegating bias conditions.It was found that the fluctuations of the channel current were directly dependent upon the sidegating bias.As the sidegating bias decreased,the amplitudes of the oscillations would increase correspondingly.Furthermore,the LFN and NLO would attenuate sharply when the sidegating bias increased to more than a certain voltage.Two mechanisms are presented to demonstrate that the effective substrate resistivity or the channel-substrate junction modulated by sidegating bias and deep level traps would take responsibilities for the LFN and NLO.展开更多
Properties of GaAs single crystals grown at low temperatures by molecular beam epitaxy ( LTMBE GaAs) have been studied. The results show that excessive arsenic atoms of about 1020 cm-3 exist in LTMBE GaAs in the form ...Properties of GaAs single crystals grown at low temperatures by molecular beam epitaxy ( LTMBE GaAs) have been studied. The results show that excessive arsenic atoms of about 1020 cm-3 exist in LTMBE GaAs in the form of arsenic interstitial couples, and cause the dilation in lattice parameter of LTMBE GaAs. The arsenic interstitial couples will be decomposed, and the excessive arsenic atoms will precipitate during the annealing above 300℃ Arsenic precipitates accumulate in the junctions of epilayers with the increase in the temperature of annealing The depletion regions caused by arsenic precipitates overlap each other in LTMBE GaAs, taking on the character of high resistivity, and the effects of backgating or sidegating are effectively restrained.展开更多
基金Project (No.KYJD09012) supported by the Fundamental Research Funds for the Central Universities,China
文摘Low-frequency noises (LFN) and noise-like oscillations (NLO) in GaAs metal semiconductor field effect transistor (MESFET) channel current were investigated under sidegating bias conditions.It was found that the fluctuations of the channel current were directly dependent upon the sidegating bias.As the sidegating bias decreased,the amplitudes of the oscillations would increase correspondingly.Furthermore,the LFN and NLO would attenuate sharply when the sidegating bias increased to more than a certain voltage.Two mechanisms are presented to demonstrate that the effective substrate resistivity or the channel-substrate junction modulated by sidegating bias and deep level traps would take responsibilities for the LFN and NLO.
文摘Properties of GaAs single crystals grown at low temperatures by molecular beam epitaxy ( LTMBE GaAs) have been studied. The results show that excessive arsenic atoms of about 1020 cm-3 exist in LTMBE GaAs in the form of arsenic interstitial couples, and cause the dilation in lattice parameter of LTMBE GaAs. The arsenic interstitial couples will be decomposed, and the excessive arsenic atoms will precipitate during the annealing above 300℃ Arsenic precipitates accumulate in the junctions of epilayers with the increase in the temperature of annealing The depletion regions caused by arsenic precipitates overlap each other in LTMBE GaAs, taking on the character of high resistivity, and the effects of backgating or sidegating are effectively restrained.
