EXPERIMENTAL SENSITIVITY ANALYSIS OF PSEUDOMORPHIC INGAAS ALAS RESONANT-TUNNELING DIODES/

Through the use of a novel vertically integrated resonant-tunneling di ode (RTD) heterostructure we have established experimentally the relat ionship between intentional variations in the structural parameters of the pseudomorphic In0.53Ga0.47As/AlAs resonant tunneling diode (i.e., barrier thickness, quantum-well thickness, quantum-well composition, and doping density) and the measured current-voltage characteristics o f the device. Based upon the results of these experiments, we have det ermined that a 1 monolayer increase in AlAs barrier width, InGaAs quan tum-well width, or InAs subwell width results in a peak current reduct ion of 56%+/-7%, 19%+/-2%, and 18%+/-3%, respectively. Further, a 1% d ecrease in indium mole fraction of the InGaAs quantum well has been fo und to increase the peak current by 10%+/-1%. Sensitivity parameters h ave been tabulated for both the peak current and the peak voltage of t he RTD. Through the use of these parameters, the maximum allowed fluct uation in the RTDs structural parameters has been estimated for a give n tolerance in the RTDs electrical characteristics. Further, these dat a can also be used to evaluate the feasibility of in situ epitaxial gr owth control of resonant tunneling devices. (C) 1995 American Institut e of Physics.