Field Dependence Of Emission Rate Research Articles

On the possible nature of deep centers in Ga2O3

The electric field dependence of emission rate of the deep traps with level near Ec−0.6 eV, so-called E1 traps, was studied by means of deep level transient spectroscopy measurements over a wide range of applied voltages. The traps were initially introduced by 900 °C ampoule annealing in molecular hydrogen. The results indicate the activation energy of the centers and the ratio of high-field to low-field electron emission rates at a fixed temperature scale as the square root of electric field, suggesting that the centers behave as deep donors. The possible microscopic nature of the centers in view of recent theoretical calculations is discussed. The most likely candidates for the E1 centers are SiGa1–H or SnGa2–H complexes.

Electron emission properties of a defect at ∼(Ec−0.23 eV) in impurity-free disordered n-GaAs

We have used deep level transient spectroscopy to study the electric-field-enhanced electron emission rate from a defect S1 observed in impurity-free disordered n-GaAs. The field dependence of emission rate could be well described by the electron emission from a Gaussian potential well with ground energy state ∼0.25eV. The phonon-assisted tunneling model with a triangular barrier could also adequately fit our experimental data for a large localized quasi-stationary energy level of ∼0.57eV. Our modeling shows that a medium-range potential is associated with S1, showing it cannot be a point defect. The possible complex structure of S1 is discussed in terms of the arsenic antisite, AsGa, and the arsenic interstitial, Asi, based on our results and by drawing on the theoretical modeling of defects in nonstoichiometric (As-rich) GaAs.

Calculation of the probability of nonradiative electronic transitions from deep centers in GaAs in the one-coordinate approximation

A study was made of the experimental optical bands of radiative VGaSAs and VGaSnGa complexes in GaAs in a wide temperature range. Parameters of the one-coordinate model of the centers were determined. The configuration-coordinate diagram of the VGaSAs complex was constructed. Using parameters of the one-coordinate model of the VGaSAs complex as the base, the field dependences of emission rates were calculated. The calculation results were compared with the experimental data. A conclusion was made that the one-coordinate model can be used for the description of the field dependence of the rate of hole emission from the VGaSAs center.

Calculation of the Parameters of a One‐Coordinate Model of the VGaSAs and VGaSnGa Complexes in Gallium Arsenide

Experimental optical bands of the emitting complexes (a gallium vacancy with a donor at the nearest, from the vacancy, sublattice site) VGaSAs and VGaSnGa in GaAs are investigated in a wide temperature range. The parameters of a one‐coordinate model of these centers are determined. A configuration‐coordinate diagram of the VGaSAs complex is constructed. Calculation of the field dependences of emission rates is carried out in terms of the parameters of the one‐coordinate model of the VGaSAs complex and the data obtained are compared with the results of experimental studies of the emission of electron holes from a deep‐lying center of the VGaSAs complex.

Field dependence of the rate of thermal emission of holes from the V Ga S As complex in gallium arsenide

An algorithm is proposed for evaluating the field dependence of the emission rate based on the form-function of optical transition. Experiment and calculations are carried out for the VGaSAs complex in a gallium arsenide crystal. The model proposed is compared with theoretical studies based on one-coordinate approximation. It is concluded that the one-coordinate model can be used to describe the field dependence of hole emission rate from the VGaSAs center.