Emission characteristics of single InGaN quantum wells on misoriented nonpolar m-plane bulk GaN substrates
InGaN single quantum wells (SQWs) grown on m-plane bulk GaN substrates show significant differences in peak emission wavelength when grown on substrates oriented nominally on-axis compared to substrates with small intentional misorientations (miscuts) towards the orthogonal −c-direction or a-direction. SQWs on substrates intentionally miscut toward the a-direction emit longer wavelengths than those with miscuts towards the −c-direction in a variety of identical growth conditions, while SQWs on nominally on-axis m-plane with pyramidal hillocks features display emission characteristics of both. These preliminary co-loaded growth studies may provide insight into broad or anomalous wavelength emission observed on nonpolar GaN-based visible light emitters and suggest opportunities for improving LED and laser diode device performance on this naturally occurring crystal plane.
• We examine emission characteristics of InGaN quantum wells on misoriented m-plane substrates.
• Blue quantum wells on on-axis m-plane substrates show broad and dual wavelength emission and non-uniform in incorporation.
• Substrates misoriented in the c- or a-direction lead to smoother film morphologies and more uniform quantum well emission.
• Substrates misoriented in the a-direction show much higher In incorporation than other m-plane substrate orientations and longer emission wavelengths.
Source: Journal of Crystal Growth