Recent advances on CW current injection blue VCSELs

Abstract

The current injection GaN-based vertical cavity surface emitting lasers with hybrid mirrors have demonstrated the CW operation at room temperature. The laser hybrid cavity composes of a 29-pair high-reflectivity AlN/GaN bottom DBR, a 7-lamda cavity region, and a 10-pair SiO2/Ta2O5 dielectric DBR. The laser structure has utilized a thin ITO layer of 30 nm as the transparent conducting layer, combining with a thin heavily doped p-type InGaN contact layer to reduce the optical loss while maintaining good current spreading capability. The laser has typical emission wavelength around 412 nm with a threshold current of about 9.7 mA at room temperature. Further details of the laser design and performance characteristics are described.