Application of compact microwave ion source to low temperature growth of transition metal nitride thin films for vacuum microelectronics devices

Abstract

A compact microwaveion source was applied to the low temperaturegrowth of transition metal nitride thin films for the cathode of vacuum microelectronics devices. An ion beam assisted deposition system consisted of a compact microwaveion source and an electron beam evaporator was developed. Depositions of zirconium nitride and niobium nitride thin films were performed and the film properties were investigated. As a result, it was found that polycrystalline films of zirconium nitride and niobium nitride were prepared at the substrate temperature as low as 500 °C, which was almost 200 °C lower than the results shown in the literature. The reason for this reduction of substrate temperature might be attributed to low gas pressure during deposition, due to the use of a single aperture ion source. The control of film composition by controlling the ion-atom arrival rate ratio achieved the control of work function. It was concluded that the ion beam assisted deposition with microwaveion source provides a possible process of cathode deposition.