[20p-E206-1~11] 3.9 Terahertz technologies

▲ [20p-E206-7] Effect of introducing phosphorous in the GaAs-based terahertz MEMS bolometers

〇Boqi Qiu¹, Ya Zhang², Kouichi Akahane³, Naomi Nagai¹, Kazuhiko Hirakawa¹ (1.IIS/INQIE UTokyo, 2.TUAT, 3.NICT)

Keywords:Terahertz bolometer, MEMS resonator

Terahertz (THz) detector is one of the crucial components in the THz technologies. Recently, we reported an uncooled, all electrical driving and detecting, very sensitive thermometer using a GaAs doubly clamped microelectromechanical (MEMS) beam resonator for bolometer applications. When the MEMS beam is heated by THz radiation, thermal expansion is induced in the MEMS beam and its resonance frequency decreases. The present device detects the frequency reduction induced by heating and works as a very sensitive thermometer. According to a simple theory, longer beams are expected to have higher thermal responsivities. However, we found that the measured responsivities of GaAs MEMS beam resonators deviates from theory due to initial deflection of the MEMS beams. In this work, we have introduced a preloaded tensile strain in the MEMS beams in order to reduce the initial deflection of the beam. We use a lattice mismatch between GaAs and GaAsP.