INFLUENCE OF QUANTUM CAPTURE AND TUNNELING MECHANISMS ON THE DARK CURRENT OF BOUND-TO-CONTINUMM QUANTUM-WELL INFRARED PHOTODETECTORS

We present a theoretical model for the dark current of bound-to-contin uum quantum-well infrared photodetectors (QWIP's), by considering the field-induced mixing effect, tunneling rate and phonon scattering rate between bound and continuum states. Using this model, we can see clea rly how these mechanisms significantly influence the Fermi levels of b ound and continuum electrons, and thus, the dark current. Nonlinear te mperature dependence of the dark current at low temperature is predict ed and discussed in detail, The simulated dark currents exhibit good a greement with the experimental results, without use of parameter fitti ng techniques.