Full text loading...
(0002) two-beam HRTEM image showing the active region of a bright green LED, extracted from a commercial device, used for the work presented here. The active region consists of four InGaN QWs separated by GaN barrier layers. The dashed square marks the area shown in Fig. 2.
(a) (0002) two-beam HRTEM image of the 2.7 nm thick QWs from a region represented as a dashed square in Fig. 1. (b) Indium distribution given as a color coded map. The resolution of the concentration map was limited to 1 nm by the Gaussian mask used for GPA. (c) Concentration profiles along the growth direction, averaged over 10 nm and (d) within the QWs and the reference GaN barrier layer averaged over a width of 1 nm.
(a) shows the subareas of the (0002) dark-field holograms from a region outlined by the dashed square in Fig. 1. (b) displays the geometric phase image covering the whole active region of the LED reconstructed from 11 dark-field images.
(a) Indium distribution map derived from the geometric phase image in Fig. 3(a). (b) The composition profile extracted along the growth direction (horizontally averaged over 40 nm). (c) The composition profiles extracted within the QWs and within the reference GaN barrier layer (averaged over a width of 1.6 nm).
Article metrics loading...