Spontaneous emission rate of green strain-compensated InGaN/InGaN LEDs using InGaN substrate

Optical properties of strain-compensated InGaN/InGaN quantum well (QW) structures using a InGaN substrate are investigated using the multiband effective mass theory. These results are compared with those of conventional InGaN/GaN QW structures using a GaN substrate. The strain-compensated QW structure shows that a smaller well thickness is needed to obtain the transition wavelength of 530 nm than the InGaN/GaN QW structure. The spontaneous emission peak of a strain-compensated QW structure is shown to be much larger than that of a conventional QW structure. This is mainly attributed to the fact that the internal field is reduced due to the decrease in the lattice mismatch with a substrate.