Monolithic integration of InGaAsP/InP semiconductor lasers using the stop-cleaving technique

In this paper we describe the stop-cleaving technique for locally cleaving the mirrors of semiconductor lasers without cleaving the entire substrate, and its applications. The technique is suitable for batch processing with a good yield and, therefore, can be applied to preparing optoelectronic integrated circuits (OEIC´s). InGaAsP/InP double-channel-planar-buried-heterostructure lasers emitting at 1.3 μm are fabricated utilizing this technique with threshold currents as low as 20 mA and differential quantum efficiencies as high as 60 percent (two facets). The implementation of this technique for preparing a monolithically integrated pair of lasers is also demonstrated. The integrated dual-laser configuration is utilized to obtain a monolithically integrated laser-detector pair by operating one of the lasers under reverse bias, and to enhance longitudinal mode discrimination by utilizing the optical feedback from the self-aligned stop-cleaved facet of the second cavity.