UV Moderation of Nitride Films during Remote Plasma Enhanced Chemical Vapour Deposition

GaN and AIN thin films have been grown by remote plasma enhanced chemical vapour deposition (RPE-CVD) with the assistance of ultraviolet (UV) irradiation during growth. High quality AIN insulating layers have been grown at room temperature for MIS devices. Film resistivities of up to 2.8 × 10¹⁶ Ω cm and breakdown fields of over 1.8 MV/cm have been achieved. Preliminary results for GaN indicate severe nitrogen loss when using UV desorption with an ammonia plasma, however no nitrogen deficit is seen when using a nitrogen plasma. Optical absorption data show substantial improvement in material quality when using a nitrogen plasma in preference to an ammonia plasma for GaN RPE-CVD growth.