Improving the peak current density of resonant tunneling diode based on InP substrate

Resonant tunneling diodes (RTD) have the potential for compact and coherent terahertz (THz) sources operating at room temperature, but their low output power severely restricts their application in THz frequency range. In this paper, two methods are adopted to increase the peak current of RTD for enhancing its output power. First, different metal contact systems (including Pt/Ti/Pt/Au and AuGe/Ni/Au) for RTD contact are introduced, and a higher current of RTD with Pt/Ti/Pt/Au contact demonstrates the superior contact characteristic of Pt/Ti/Pt/Au contact system. Second, the double barrier structure (DBS) of RTD is well designed to further improve the characteristic of RTD, and a high peak current of 154 kA/cm² is achieved at room temperature. The improved peak current is very beneficial for increasing the output power of RTD oscillator.