GaN-based vertical cavity surface emitting lasers with lateral optical confinements and conducting distributed Bragg reflectors
Ryosuke Iida, Yusuke Ueshima, Wataru Muranaga, Sho Iwayama, Tetsuya Takeuchi, Satoshi Kamiyama, Motoaki Iwaya, Isamu Akasaki
Abstract
Abstract We aimed to further improve performances of GaN-based vertical cavity surface emitting lasers (VCSELs) by applying a combination of conducting distributed Bragg reflectors (DBRs) and lateral optical confinement structures simultaneously, generally used in GaAs-based VCSELs. Si-doped conducting AlInN/GaN DBRs and buried SiO 2 apertures were adopted in the GaN-based VCSELs. By comparing the VCSELs and micro LEDs to those with undoped non-conducting DBRs, we found that lower device resistances and more uniform lateral current distributions were obtained with the conducting DBRs. At the same time, the maximum light output power of 2.6 mW was observed from the VCSEL with the conducting DBR while 4.4 mW was obtained from the VCSEL with undoped DBR. Inferior characteristics of a GaInN quantum well active region was found on the Si-doped conducting DBR.