All-gaseous doping during chemical-beam epitaxial growth of InGaAs/InGaAsP multi-quantum-well lasers

Abstract

The use of all-gaseous doping during chemical-beam epitaxy (CBE) offers several important advantages. Injection of dopants, together with the metalorganic group-III beam, automatically leads to uniform dopant distribution across the entire wafer. Vapor dopant sources also ensure long-term stability and reproducibility. It also allows for instant doping profile control. Most important of all, an all-gaseous doping CBE system is particularly attractive for system manufacture and device production applications. We investigated n- and p-type dopings in InP and InGaAs during CBE using tetraethyltin (TESn) and diethylzinc (DEZn), respectively, and confirmed their suitability for use in growing high-quality long-wavelength InGaAs(P)/InGaAsP semiconductor injection lasers. Buried heterostructure lasers fabricated from CBE-grown 1.5-μm six quantum-well base wafers and metalorganic vapor-phase-epitaxy regrown iron-doped InP have excellent current-voltage characteristics and threshold currents as low as 8 mA. cw operation with threshold current as low as 23 mA at 80 °C and output power of ∼10 mW was achieved for diodes having one facet ∼85% reflective coated.