FABRICATION OF BROAD-AREA LASER-DIODES ON A 3-INCH WAFER BY A SOLID-PHASE DIFFUSION METHOD

We have developed extremely uniform Zn diffusion on a three-inch GaAs 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 (1 sigma), emission wavelength is 879.7+/-0.6 nm (1 sigma). Such high uniformity is caused by not only uniform Zn diffusion but also uniform epitaxial layer thickness over a three-inch wafer.