Quasistatic capacitance-voltage characteristics of plane-parallel structures: Metal/semi-insulator/metal

Quasistatic capacitance-voltage characteristics of plane-parallel structure s of the semi-insulating GaAs with two metal contacts are calculated numeri cally. The model of residual shallow acceptors compensated for by an excess of deep donors is used for the semi-insulating GaAs. Under consideration i s the relaxation regime for the charge transport in the semi-insulator. We analyze metal/semi-insulator/metal structures for various parameters of the metal contacts and of the semi-insulator. It is shown that a negative capa citance can be obtained in some cases. A more detailed analysis is performe d for the following structure: p-type like metal contact/n-type semi-insula tor/n-type like metal contact. (C) 2000 American Institute of Physics. [S00 21- 8979(00)01516-4].