Weakly Index Guided Buried-Stripe Type 980 nm Laser Diodes Grown by a Combination of Gas Source Molecular Beam Epitaxy and Metalorganic Vapor Phase Epitaxy with an AlGaAs/InGaP/GaAs Double Etch Stop Structure

• Published in: Japanese Journal of Applied Physics Vol. 38; no. 10R; p. 5888
• Main Authors: Horie, Hideyoshi, Nagao, Satoru, Shimoyama, Kenji, Fujimori, Toshinari
• Format: Journal Article
• Language: English
• Published: 01-10-1999
• ISSN: 0021-4922; 1347-4065
• DOI: 10.1143/JJAP.38.5888

In order to fabricate weakly index guided buried-stripe type 980 nm laser diodes (LDs)
precisely and reproducibly, we have developed a novel double etch stop (DES) structure
which consists of AlGaAs/InGaP/GaAs layers. By employing the DES structure, an
effective refractive index step (Δ
n
eff
) of 3.6×10
-3
and a waveguide bottom width (
W
b
) of
2.2 µm were realized to maintain a stable transverse mode. The LDs were fabricated by
a combination of gas-source molecular beam epitaxy (GS-MBE) and metalorganic vapor
phase epitaxy (MOVPE) on a 2-inch wafer and showed uniformly high performance,
especially in the region within a 15.5 mm radius from the center. A high kink level of
315±15 mW was achieved. Considering wafer uniformity, we estimated that Δ
n
eff
and
W
b
should be controlled to about 3.6×10
-3
±
3.5×10
-4
and 2.22±0.06 µm, respectively,
under the condition of a vertical optical confinement factor
\varGamma\fallingdotseq1.16%/well. We have
also confirmed the high quality of the entire process, including the DES method, by
employing a reliability test at 200 mW light output power up to
2500 h.