US Patent 7588954 InGaAs/GaAs lasers on silicon produced by LEPECVD and MOCVD

Method for making an InGaAs/GaAs quantum well laser (10) on a Silicon substrate (15.1). The method comprises the steps:Formation of a virtual Germanium substrate (15) on the Silicon substrate (15.1) by means of a low-energy plasma-enhanced chemical vapourdeposition (LEPECVD). The virtual Germanium substrate (15) comprises a pure Germanium layer (15.3).Formation of a Gallium Arsenide structure on the virtual Germanium substrate (15) by means of a metal organic chemical vapour deposition process. The metal organic chemical vapour deposition process comprises the steps:formation of a first Gallium Arsenide layer (16) on the virtual Germanium substrate (15) at a first substrate temperature (Ts1),formation of a second Gallium Arsenide waveguide layer (17) at a second substrate temperature (Ts2), the second substrate temperature (Ts2) being higher than the first substrate temperature (Ts1) and the first Gallium Arsenide layer (16; 21) being thinner than the second Gallium Arsenide layer (17),formation of an active laser structure comprising a Gallium Arsenide waveguide layer (12) embedding a quantum well (11).