Design And Fabrication Of High Power Vertical Cavity Surface Emitting Laser

Vertical-cavity surface-emitting lasers (VCSELs) have emerged as attractive light sources for various applications in optical communication, optical computing, optical interconnects, laser printing, and optical storage, etc. The main advantages are their low-cost fabrication and packaging, low drive currents, low divergence circular beams, and the possibility of integration in 1-D and 2-D arrays with high density. Over the past few years, the excellent performance of oxide-confined VCSELs has been reported in the literatures in terms of low threshold current, high output power, high wall-plug efficiency, low operating voltages, a high intrinsic modulation bandwidth, as well as very high fabrication yields. Here, designs and key techniques have been presented for high power VCSELs. Contents are in detail as follows:1. Distributed Bragg reflectors (DBRs) have been optimally designed. Testing results show that these DBRs have high peak reflectivity with low series resistance, which makes the heat generated by series resistance of the device reduced greatly.2. Optimizing active layer and cavity is to increases injected current carriers into quantum wells and reduce lateral current leakage and optical scattering loss. Thus, active region can provide lasing mode with great light gain efficiency.3. Optimal design has been done on Al_xGa_1-xAs layer with high Al content, which will be oxided for current and light confinement, taking into account effects of thickness and position on lasing mode, as well as stress resulting from oxidation of Al_xGa_1-xAs layer with high Al content. The layer position has been adjusted by being placed in the fourth DBR pair above the active region to suppress oxidation mode and relieve stress effect on active layer. Further more, the oxidation layer placed on anti-node...