OPTIMIZATION OF MOVPE GROWN INXAL1-XAS IN0.53GA0.47AS PLANAR HETEROEPITAXIAL SCHOTTKY DIODES FOR TERAHERTZ APPLICATIONS/

The feasibility of InP-based planar heteroepitaxial diodes for teraher tz multiplier and mixer applications is explored. A variety of InxAl1- x As/In0.53Ga0.47As (x = 0.52, 0.4) diodes have been grown using LP-MO VPE and allows systematic characterization of the effects of barrier t hickness, InAs mole fraction and active layer thickness on the diode D C and RF performance. A new fabrication technology is developed for pl anar diodes using dielectric-free air-bridged anode fingers and trench isolation to minimize series resistance and parasitic capacitance. A qualitative model is suggested to explain the forward current conducti on mechanism of the reported diodes. The control of forward current co nduction and reverse leakage by epitaxial design together with the dem onstrated figure-of-merit cutoff frequency of 2.6 THz make the diodes suitable for multiplier and mixer terahertz applications.