Subpicosecond carrier lifetime in beryllium-doped InGaAsP grown by He-plasma-assisted molecular beam epitaxy

Combination of He-plasma-assisted growth with Be doping is demonstrated to facilitate for further reduction of carrier lifetime to subpicosecond. With moderate doping concentrations, a relatively sharp absorption edge is maintained. Five 2-μm-thick InGaAsP samples grown on InP substrates were investigated and compared. There is little difference in the slope of the band edge between the standard sample and the He plasma sample.