High reliable, low threshold 1.3 μm SL-QW PACIS (p-substrate Al-oxide Confined Inner Stripe) laser array

A 1.3 μm Al-oxide confined inner stripe laser on p-InP substrate (PACIS) has been demonstrated for low cost laser array application. First, we have investigated the oxidation rate of Al_x In_1-xAs layer grown on InP substrate. The optimum conditions were found to be oxidation temperature=500°C, layer thickness=100 nm, and Al-contents=0.48 (lattice-match) taking oxidation rate and surface morphology into account. The 50 nm-thick Al_0.48 In_0.52As-oxide layer provides good current blocking for laser applications. Based on the above investigations, the fabricated PACIS laser shows a low threshold current of 4.0 mA and a high slope efficiency of 0.6 W/A. We have also confirmed high reliability under driving time over 3,000 hours at 85°C, 5 mW. A 22-channel laser array consisted of PACIS structure have the average threshold current of 3.98 mA and the standard deviation of 0.42 mA