Effect of Silicon Doping Profile on I–V Characteristics of an AlGaAs/GaAs Resonant Tunneling Barrier Structure Grown by MBE

The effect of Si doping profile on I–V characteristics of an AlGaAs/GaAs resonant tunneling barrier (RTB) structure was studied by changing the thickness of an undoped GaAs “spacer” layer placed adjacent to the RTB. We found that the peak and the valley current density in the negative differential resistance region at 77 K depends strongly on the thickness of the spacer layer. By using a spacer layer of 50 Å, we achieved a resonant tunneling diode with the highest peak current density of 2×10 4 A/cm 2 with a good peak-to-valley ratio of 3.5 at 77 K.