High-efficiency BGaN/AlN quantum wells for optoelectronic applications in ultraviolet spectral region

Light emission characteristics of ultraviolet (UV) BGaN/AlN quantum well (QW) structures were investigated using the multiband effective-mass theory and non-Markovian model. The BGaN/AlN QW structures show a much larger light intensity than the conventional AlGaN/AlN QW structures. This is mainly due to the fact that the internal field is significantly reduced by increasing boron contents. The spontaneous emission peak shows a maximum at the critical value (x= 0.04) and begins to decrease when the boron content is further increased. Hence, we expect that BGaN/AlN QW structures with small boron contents can be used as a TE-polarized light source with a high efficiency in UV region.