Fabrication of broad-area laser diodes on a three-inch wafer by a solid-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/spl plusmn/8.3 mA (1/spl sigma/), emission wavelength is 879.7/spl plusmn/0.6 nm (1/spl sigma/). Such high uniformity is caused by not only uniform Zn diffusion but also uniform epitaxial layer thickness over a three-inch wafer. >