Towards terahertz circuits via InP micromachining techniques

By using micromachining techniques, InP-based heterostructure barrier varactor (HBV) devices having different topological structures have been fabricated on a glass host substrate following an epitaxial transfer technique. The device characteristics have been measured and compared with devices which have been fabricated on InP substrate. The devices exhibited highly symmetrical electrical characteristics due to the preservation of the high quality MBE layers during the transfer process. A leakage current of 7 A/cm/sup 2/ at 8 V together with an associated conductance value of 78 nS//spl mu/m/sup 2/ were observed. RF measurements revealed a zero bias capacitance of 1.7 fF//spl mu/m/sup 2//barrier and a capacitance ratio of 5:1.