HighTemperature Characteristics of AlAs/GaAs/AlAs Resonant Thnneling Diodes

This article reports the high-temperature de characteristics of double-barrier AlAs/GaAs/AlAs resonant tunneling diodes, over the temperature range 22°C to 185°C. The negative differential resistance of these quantum-well structures persisted up to the highest temperature; over this temperature range of 163°C, the peak current increased slightly (?>5%), but the valley current increased significantly (180%), resulting in a reduction of the peak-to-valley current ratio from 3.5 at 22°C to 1.3 at 185°C. The slight change in the peak current indicated that the diodes were of high quality and that tunneling was the dominant conduction mechanism. The difference between the voltage at the valley and at the peak decreased from 115mV at 22°C to 80 mV at 185°C. Between 125°C and 185°C, the valley current as a function oftemperature could be fitted to an Arrhenius-type dependence with an activation energy of 120meV.Although these quantum-well diodes appear usable to at least 185°C, the temperature dependence of the peak-to-valley current ratio and voltage difference would significantly affect their performance, such as switching speed, oscillator power, or cutoff frequency, for digital or analog circuit applications at high temperatures.