DC and RF characterization of different heterojunction interband tunneling diodes

Tunnel diodes are semiconductor devices with the unique property of negative differential resistance (NDR). These devices show great potential for power generation at high frequencies. Heterostructure interband tunneling diodes (HITDs) when integrated with heterojunction FETs (HFETs) produce a three-terminal device that we call a HITFET. The NDR characteristics of a HITFET can be controlled by either the gate or drain biases. Devices and circuits based on HITDs and HITFETs have shown great promise and are being considered in many digital and analog applications. To satisfy the variety of matching conditions for the combination of the different devices and to facilitate the integration, it is important to have flexibility and good control over the tunnel diode electrical characteristics. We report our investigation of HITDs in the In_0.53Ga_(0.47)As/In_(0.52)Al_(0.48) As/InP material system. We study and optimize the dependence of the tunnel diode peak current density on p⁺ doping levels, quantum well widths, and doping layer thicknesses. We also introduce a new interband tunnel diode structure with almost an order of magnitude higher peak current density (~40,000A/cm²) while maintaining a reasonable peak to valley current ratio of approximately 20. We investigate the high frequency properties of these tunnel diodes and compare the new and the conventional HITD performance