Selective epitaxy of InGaN/GaN multiple quantum wells on GaN side facets

Selective area epitaxy has been applied to grow GaN stripe templates with side facts, followed by InGaN/GaN multiple quantum well (MQW) structures. Stripes oriented along the direction of [1 1 −2 0] form smooth triangular {1 −1 0 1} facets, while stripes in the [1 −1 0 0] direction produce incomplete coalesced {1 1 −2 2} side facets with planar (0 0 0 1) surface under the same growth conditions. Room-temperature luminescence property is investigated by using photoluminescence (PL) and cathodeluminescence (CL) spectra. It is found that uniform emission at 400 nm has been obtained for triangular MQWs oriented the direction of [1 1 −2 0]. With respect to the MQWs grown along the [1 −1 0 0] direction, large redshift is achieved for the ridge area compared to the sidewall due to the lateral vapor diffusion and surface migration.

▶ We compare the InGaN/GaN multiple quantum well stripes grown along [1 1 −2 0] and [1 −1 0 0] directions. ▶ The local indium content of the MQW stripes have been investigated and compared. ▶ Polychromatic emissions have been obtained on one single chip.