Fabrication of broad-area laser diodes on a three-inch wafer by asolid-phase diffusion method

We have developed extremely uniform Zn diffusion on a three-inch GaAs-AlGaAs QW laser wafer by an open tube solid-phase diffusion technique and have applied it to fabrication of broad-area laser diodes (LD's) for the first time using 3-inch full-wafer processing. Excellent uniformity of device characteristics have been obtained on a 3-inch wafer; threshold current distribution along the radial direction of a wafer is 356.2±8.3 mA (1σ), emission wavelength is 879.7±0.6 nm (1σ). Such high uniformity is caused by not only uniform Zn diffusion but also uniform epitaxial layer thickness over a three-inch wafer