Capacitance spectroscopy of hole traps in high-resistance gallium-arsenide structures grown by liquid-phase epitaxy

Resumo

Three deep acceptor levels with activation energies of ~0.7, ~0.41, and ~0.16 eV are found in GaAs structures, which have the hole type of conductivity and are grown by liquid-phase epitaxy, by the methods of capacitance spectroscopy (admittance spectroscopy and deep-level transient spectroscopy). The first two levels are known as HL2 and HL5 and are related to the features of GaAs-layer growth by liquid-phase epitaxy. They are effective recombination centers determining reverse currents in p–i–n diodes, which is confirmed by studying the temperature dependences of reverse currents. The level with the energy E_v + 0.16 eV can be related to the two-charge acceptor level of the inherent antisite defect in GaAs, which also determines the doping concentration of structures in the singly charged state.