Electrical field mapping in InGaP HEMTs and GaAs terahertz emitters using backside infrared OBIC technique.

摘要

Electric potential and field are probed in selected III-V devices by backside infrared (1.3 μm wavelength) optical beam induced current (OBIC) technique under the DC and transient conditions. In an InGaP/InGaAs high electron mobility transistor (HEMT), the OBIC signals is sensitive to the distribution of electrical potential profile in the InGaP/InGaAs heterostructure and to the technological treatment (dry/wet etching). In a semi-insulating GaAs THz Emitter, the OBIC signal reflects well the lateral distribution and dynamics of the electric field. The physical origin Of the OBIC signal is discussed in details.