CBE grown (GaIn)(AsP) laser diodes for monolithic integration

Selective in-filling growth by chemical beam epitaxy (CBE) is ideally suited for the monolithic integration of InP-based laser diodes and photonic devices. The growth was carried out on exactly oriented (100) n-InP substrates as well as on 2 degrees off toward next [110] oriented substrates. The preparation of the substrates and the growth parameters, e.g. growth rate, strongly influences the shape and optical properties of embedded (GaIn)(AsP) laser diodes shown by scanning electron microscopy (SEM) and spatially resolved cathodoluminescence (CL) measurements. By reducing the growth rate from 1.3 mu m/h to 0.4 mu m/h at a high V/IIIBEP ratio of 18 during the gowth of the InP buffer flat layers are grown within narrow grooves. Separate confinement heterostructure (SCH) multi quantum well (MQW) laser diodes (lambda = 1.55 mu m) with cleaved mirrors selectively in-filled in 3 mu m wide grooves show a device performance comparable to conventional 'state of the art' quaternary laser diodes; e.g. lasers with 6 QW show threshold currents of 16 mA and light output of several mW in CW operation. By butt joining we integrated quaternary ridge waveguide (RW) laser diodes and waveguides.