Highly Efficient Ultra-Violet Luminescence from Low-Temperature Grown AlGdN

Abstract

We have investigated the narrowband ultraviolet (UV) emission characteristics of Al_0.94Gd_0.06N grown by reactive magnetron sputtering in an ultra-pure process. A resolution limited, narrow band luminescence line from Gd³⁺ ions has been observed at ∼320nm. The crystallographic properties of the Al_0.94Gd_0.06N thin films are sensitive to the growth temperature. With a decrease in the growth temperature, the emission efficiency has been found to increase considerably. According to the crystallographic properties investigated by extended X-ray absorption fine structure analysis, fluctuation of the column-III sublattices around the Gd³⁺ ions plays a key role to enhance the luminescence intensity.