Optimal design for improving performance of VCSELs

A new device structure is reported to improve performance of vertical cavity surface-emitting lasers (VCSELs). Namely many cylindrical holes (CH) or noncontiguous ring trench (NRT) are etched instead of the conventional ring trench (RT). The mesa with such new structure offers radial bridges for current injection, the connecting Ti-Au metal between ohmic contact and bonding pad does not have to cross the ring trench, and it would not cause the connecting metal broken. The 850nm VCSELs with CH have a light output power higher than 10 mW and have a maximum of 12.5 mW at 29.6 mA, 1.34 times as much as those with RT. And the 980nm VCSELs with NRT have a maximum light output power of 28.8 mW at 49.5 mA, 1.6 times as much as those with RT. In addition, these new structure VCSELs also show high-temperature operation characteristics.