Vol. 32, No. 6 Journal of Semiconductors June 2011 Characteriz developed for operation at room temperature . A self- 1. Introduction mixing model based on the resistive network of the field-effect transistor is found to be adequate for analyzing devices operat- Compared to the relatively slow detectors that are based ing in the non-resonant detection regime. Here, we report THz on calorimetric or bolometric effects, such as pyroelectric (PE) detection by a modified GaN/AlGaN high-electron-mobility detectors and silicon bolometers, solid-state terahertz (THz) transistor (HEMT), in which three THz patch antennas are en- electromagnetic radiation detectors that operate at room tem- gineered in a way so that THz radiation is effectively coupled perature may offer both high sensitivity and high speed. Such to the source, drain and gate electrodes. An attempt to find the superior characteristics are paramount for realising practical physical origin of terahertz photocurrent is described and we THz receivers for imaging, communication and radar appli- verify that the device operates as a mixer around 1 THz. cationsŒ1. One candidate is the direct-sensing Schottky diode already widely used in
