Electrical and thermal properties of photoconductive antennas based on InxGa1 – xAs (x > 0.3) with a metamorphic buffer layer for the generation of terahertz radiation

Abstract

The results of studies of the electrical and thermal properties of photoconductive antennas for terahertz-radiation generation are reported; these antennas are fabricated on the basis of low-temperaturegrown GaAs (LT-GaAs) and In_xGa_{1 – x}As with an increased content of indium (x > 0.3). It is shown that the power of Joule heating PH due to the effect of “dark” current in In_xGa_{1 – x}As exceeds the same quantity in LT-GaAs by three–five times. This is due to the high intrinsic conductivity of In_xGa_{1 – x}As at x > 0.38. Heatremoval equipment for the photoconductive antenna has been developed and fabricated. The results of numerical simulation show that the use of a heat sink makes it possible to reduce the operating temperature of the antenna based on LT-GaAs by 16%, of the antenna based on In_0.38Ga_0.62As by 40%, and for antennas based on In_0.53Ga_0.47As by 64%.