TEMPERATURE EFFECTS ON AlGaAs/GaAs DOUBLE BARRIER DIODES WITH HIGH PEAK-TO-VALLEY CURRENT RATIOS.

Recent advances in molecular-beam-epitaxy (MBE) technology have made possible the fabrication of heterojunction double-barrier diodes (DBDs) with high peak-to-valley current (PVC) ratios. Results from a DC current-voltage (I-V) study of AlGaAs/GaAs double-barrier diodes from 40 K to 300 K are presented. To separate the competing conduction mechanisms, each sample was examined at the following bias conditions: (1) low voltage; (2) peak current; and (3) valley current. The experimental results indicate that the low-bias current is dominated by thermally assisted tunneling through the well eigenstate; the peak current is dominated by sequential or resonant tunneling through the eigenstate; and the valley current is dominated by nonresonant tunneling and thermal currents. These results provide insight into the DBD conduction and point to potential design criteria for optimum device performance.