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

Through the use of a novel vertically integrated resonant-tunneling diode (RTD) heterostructure we have established experimentally the relationship 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 of the device. Based upon the results of these experiments, we have determined that a 1 monolayer increase in AlAs barrier width, InGaAs quantum-well width, or InAs subwell width results in a peak current reduction of 56%+/-7%, 19%+/-2%, and 18%+/-3%, respectively. Further, a 1% decrease in indium mole fraction of the InGaAs quantum well has been found to increase the peak current by 10%+/-1%. Sensitivity parameters have been tabulated for both the peak current and the peak voltage of the RTD. Through the use of these parameters, the maximum allowed fluctuation in the RTDs structural parameters has been estimated for a given tolerance in the RTDs electrical characteristics. Further, these data can also be used to evaluate the feasibility of in situ epitaxial growth control of resonant tunneling devices. (C) 1995 American Institute of Physics.