Gas source MBE of InP and GaxIn1−xPyAs1−y : Materials properties and heterostructure lasers

Abstract

The growth of useful GaxIn1−xPyAs1−y by MBE is inhibited by the difficulty in maintaining precise control over the flux from condensed source As and P effusion ovens. The use of P2 and As2 beams generated from the cracking of PH3 and AsH3 as an alternative approach is reviewed and new data are presented. Accommodation coefficients were determined for P2 and As2 on heated InP and GaAs surfaces. The flux composition as a function of epitaxial layer composition was determined for the lattice-matching quaternary. Studies of doping were done and injection laser structures were grown. Although detailed studies of layer composition control were not done, the achievable control seems quite adequate for injection lasers. A variety of heterostructure lasers emitting at nominally 1.5 μm with broad area 300-K threshold-current densities from 1300 to 2400 A/cm2 were demonstrated. Ridge waveguide lasers fabricated from the same wafers had Ith of about 40 mA and differential efficiencies of 36%–45%. They lased cw to 50 °C.