ScAlN/GaN High Electron Mobility Transistor Heterostructures Grown by Ammonia Source Molecular Beam Epitaxy on Silicon Substrate

In this work, ammonia source molecular beam epitaxy is explored as an alternative technique to grow ScAlN/GaN high electron mobility transistor heterostructures on a silicon substrate with thin buffer layers. The effect of ScAlN barrier thickness is investigated. A transistor with a maximum drain current superior to 1 A mm −1 has been fabricated on a silicon substrate despite the ohmic contacts having a resistance around 1 ohm.mm, and functional transistors with barriers as thin as 10 nm have been demonstrated.