Citation: |
Meixin Feng, Qian Sun, Jianping Liu, Zengcheng Li, Yu Zhou, Hongwei Gao, Shuming Zhang, Hui Yang. Al-free cladding-layer blue laser diodes with a low aspect ratio in far-field beam pattern[J]. Journal of Semiconductors, 2018, 39(8): 084004. doi: 10.1088/1674-4926/39/8/084004
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M X Feng, Q Sun, J P Liu, Z C Li, Y Zhou, H W Gao, S M Zhang, H Yang, Al-free cladding-layer blue laser diodes with a low aspect ratio in far-field beam pattern[J]. J. Semicond., 2018, 39(8): 084004. doi: 10.1088/1674-4926/39/8/084004.
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Al-free cladding-layer blue laser diodes with a low aspect ratio in far-field beam pattern
DOI: 10.1088/1674-4926/39/8/084004
More Information
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Abstract
c-plane GaN-based blue laser diodes (LDs) were fabricated with Al-free cladding layers (CLs) and deepened etching depth of mesa structure, so the aspect ratio of the far-field pattern (FFP) of the laser beam can be reduced to as low as 1.7, which is nearly the same as conventional AlGaInP-based red LDs. By using GaN CLs, the radiation angle of the laser beam θ⊥ is only 10.1° in the direction perpendicular to the junction plane. After forming a deeply etched mesa, the beam divergence angle parallel to the junction plane of FFP, θ//, increases from 4.9° to 5.8°. After using the modified structure, the operation voltage of LD is effectively reduced by 2 V at an injection current of 50 mA, but the threshold current value increases. The etching damage may be one of the main reasons responsible for the increase of the threshold current. -
References
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