Numerical Analysis and Lasing Characteristics of GaInAsP Double-Heterostructure Lasers on InP/Si Substrate

Deposition of GaInAsP crystalline layer structures on a directly bonded InP/Si substrate for the fabrication of a laser diode device was explored using conventional metal–organic vapor-phase epitaxy (MOVPE) growth technology. In particular, one of the remarkable strategies that we have introduced is the ability to make a firm bonding of an InP epi-layer adhered to the Si substrate before the growth of the GaInAsP layer structures. In previous studies, a 1.2 μm-wavelength laser diode on InP/Si substrate was achieved. To further the research on laser growth, the epitaxial layer structures were numerically studied and analyzed. It was found that the performance of the laser was very efficient in increasing the p-cladding layer thickness. An analysis was also performed on the n-cladding layer to determine the power in the silicon substrate. When the n-cladding layer thickness was increased, the power in the silicon substrate was dramatically decreased. We realized that the n-cladding layer influences the confinement factor in the active layer. The confinement factor and threshold current density (Jth) of the n-cladding layer were also calculated numerically. In this paper, we report the numerical analysis and lasing characteristics of 1.5 µm telecommunication wavelength double-heterostructure lasers on the directly bonded InP/Si substrate and also a subsequent comparison of threshold current density between the InP/Si laser diode (LD) and the standard InP laser diode substrate.