High performance InP-based heterostructure barrier varactors in single and stack configuration

Single (SHBV) and dual (DHBV) heterostructure barrier varactors with AlAs/In0.52Al0.48As blocking conduction layers have been fabricated and characterised. The devices, whose electrical properties scale with layer complexity, exhibit, for a DHBV scheme, leakage currents as low as 10 A/cm(2) at 12 V, a zero bias capacitance of 1 fF/mu m(2), and a capacitance ratio of 5:1.