INXGA1-XAS INP QUANTUM-WELL STRUCTURES GROWN ON [111]B INP/

We report growth and characterization details of lattice matched and c oherently strained InxGa1-xAs/InP quantum well structures grown on mis oriented [111]B InP substrates. Photoluminescence from a range of such structures, grown on substrates with optimum misorientation, show lin ewidths as good or better than equivalent [100] layers. Multiquantum w ell (MQW) samples with relatively modest compressive strain show X-ray diffraction data characteristic of highly uniform pseudomorphic quant um wells. With increased strain (x = 0.63), relaxation is evident thro ugh a degradation of the diff acted peak widths and through the observ ation of defects in the surface morphology. Fabricated strained p-i(MQ W)-n diode structures exhibit low reverse leakage current densities (e .g. j = 6 mu A/ cm(2)). Room temperature photocurrent measurements on these devices show a strong excitonic blue shift (15 nm) with applied bias, as a consequence of the built-in piezoelectric field. The rate o f peak shift, up to 8 nm/V, demonstrates excellent potential for low v oltage optical modulator applications at around 1.55 mu m wavelength.