Migration effect from a masked region for InGaAsP-selective MOVPE

A novel method is proposed for identifying the effective surface migration length in a dielectric-masked region by introducing the concept of obtaining the threshold mask width for the vapor phase diffusion effect. SEM observations were made to evaluate the thickness of selectively grown layers. Micro-area photoluminescence (μ-PL) measurements at room temperature were used for estimating the bandgap wavelength of the selectively grown layers. The crystal compositions of selectively grown InGaAsP layers were calculated from the layer thickness and PL wavelength including both the quantum effect and strain effect. We have found that the surface migration effect and vapor phase diffusion effect have different mask width dependences for the growth rate and composition change