The local vibration mode(LVM)of carbon acceptor in GaAs is studied by measuring directly the change in LVM absorption with a NIC-170 SX FT-IR spectrometer.The change in the charge state of carbon acceptor and the temp...The local vibration mode(LVM)of carbon acceptor in GaAs is studied by measuring directly the change in LVM absorption with a NIC-170 SX FT-IR spectrometer.The change in the charge state of carbon acceptor and the temperature dependence of the LVM absorption were investigated also.The contents of the impurities other than carbon were estimated by secondary ion mass spectrometry.It is observed that the frequency,the spectral form and the integrated absorption of the LVM are not affected by the change in charge state of car- bon acceptor.展开更多
Undoped semi-insulating (SI) LEC GaAs samples were investigated. The concentrations of ionized EL2and carbon acceptor were measured by multiple wavelength infrared absorption and local vibrational modeinfrared absorpt...Undoped semi-insulating (SI) LEC GaAs samples were investigated. The concentrations of ionized EL2and carbon acceptor were measured by multiple wavelength infrared absorption and local vibrational modeinfrared absorption methods. The results indicate that for the same sample the ionized EL2 concentration([EL2￣+]) is higher than the carbon acceptor concentration ([C]). The value of [EL2￣+]-[C] is of the order ofmagnitude of 10￣(15) cm￣(-3), which means that acceptors other than carbon exist with a concentration of10￣(15) cm￣(-3) in the samples. This is in conflict with the conventional 3-level compensation model. The radialdistribution of [EL2￣+] was investigated. The radial distribution of carbon acceptor does not present any regu-larity.展开更多
The local vibrational mode (LVM) optical absorption band of carbon acceptor was investigated carefully. Because of the appearance of a sideband on the low energy side of the LVM main absorption band, it is found that ...The local vibrational mode (LVM) optical absorption band of carbon acceptor was investigated carefully. Because of the appearance of a sideband on the low energy side of the LVM main absorption band, it is found that the measured value of the integrated area for the main absorption band is sensitive to the choice of integration baseline wavenumber range (BWR). This is the main cause that the experimental results from different investigators show a wide spread for the temperature dependence of the integrated area. The origin of the sideband is also discussed.展开更多
文摘The local vibration mode(LVM)of carbon acceptor in GaAs is studied by measuring directly the change in LVM absorption with a NIC-170 SX FT-IR spectrometer.The change in the charge state of carbon acceptor and the temperature dependence of the LVM absorption were investigated also.The contents of the impurities other than carbon were estimated by secondary ion mass spectrometry.It is observed that the frequency,the spectral form and the integrated absorption of the LVM are not affected by the change in charge state of car- bon acceptor.
文摘Undoped semi-insulating (SI) LEC GaAs samples were investigated. The concentrations of ionized EL2and carbon acceptor were measured by multiple wavelength infrared absorption and local vibrational modeinfrared absorption methods. The results indicate that for the same sample the ionized EL2 concentration([EL2￣+]) is higher than the carbon acceptor concentration ([C]). The value of [EL2￣+]-[C] is of the order ofmagnitude of 10￣(15) cm￣(-3), which means that acceptors other than carbon exist with a concentration of10￣(15) cm￣(-3) in the samples. This is in conflict with the conventional 3-level compensation model. The radialdistribution of [EL2￣+] was investigated. The radial distribution of carbon acceptor does not present any regu-larity.
文摘The local vibrational mode (LVM) optical absorption band of carbon acceptor was investigated carefully. Because of the appearance of a sideband on the low energy side of the LVM main absorption band, it is found that the measured value of the integrated area for the main absorption band is sensitive to the choice of integration baseline wavenumber range (BWR). This is the main cause that the experimental results from different investigators show a wide spread for the temperature dependence of the integrated area. The origin of the sideband is also discussed.
