Molybdenum low-resistance thin-film resistors for cryogenic devices

Abstract

We present a study of thin-film Mo resistors for NbN electronics operating at cryogenic temperatures. The key step is the 0.5–1.5 keV ion cleaning–activation of NbN before Mo deposition, which allows us to obtain a high-quality Mo/NbN interface. This, together with an additional Al bandage layer in the area of the contact pads, allows us to reduce the contact resistance below 1 Ω. The quality of the interfaces is confirmed by transmission electron microscopy and x-ray reflectometry.