A microstructure in an InGaN/GaN layer grown at the semi-polar direction was observed in detail by means of transmission electron microscopy in order to analyze the behaviour of dislocations. A (11•2) GaN layer was first deposited on a mask-less r (1¯1•2)-plane patterned-substrate, and then an InxGa1-xN (x = 0.10, 0.24) was overgrown to be about 1μm in thickness. Dislocations near the interface of InGaN/GaN were classified into several types: threading dislocations lying on (00•1), misfit dislocations lying on the interface of InGaN/GaN, dislocations along [1¯1•0] at a certain distance from the interface, dislocations newly formed at the interface and developing along [11•0] on (00•1), partial dislocations accompanied by a stacking fault on (00•1). It was found that the misfit dislocations were arrayed in pairs at the direction along [1¯1•0] on the interface of (11•2). Burgers vector of the misfit dislocations was found to be b = <2¯1•3>/3. In the case of b = [¯1¯1•3]/3, they were edge dislocations. The densities of dislocations and stacking faults increased with the In-content in InGaN.

Behavior of Misfit Dislocations in Semipolar InGaN/GaN Grown by MOVPE. T.Kuwahara, N.Kuwano, A.Kurisu, N.Okada, K.Tadatomo: Physica Status Solidi C, 2012, 9[3-4], 488-91