Low loss AlInN/GaN Monolithic Microwave Integrated Circuit switch

We report on the first AlInN/GaN Heterojunction Field Effect Transistor (HFET) based Monolithic Microwave Integrated Circuit (MMIC) switch. Lattice-matched AlInN/GaN heterostructures with indium contents of ~17% exhibit a very large conduction band discontinuity, ΔE_C, of 1.7 eV. This large discontinuity results in 2D EG densities as high as 4.7x10¹³ cm^-2 and electron mobilities as high as 1617 cm²/V-s. As a result these heterostructures can achieve record low sheet resistances, making them very attractive candidates for ultra-low loss microwave and other switching devices.