Preparation of low defect density of III-V on Si for device fabrication
View Patent ↗A method of forming a semiconducting material includes depositing a graded buffer on a substrate to form a graded layer of an indium (In) containing III-V material, the In containing III-V material being indium-gallium-arsenic (InGaAs) or indium-aluminum-arsenic (InAlAs) and comprising In in an increasing atomic gradient up to 35 atomic % (at. %) based on total atomic weight of InGa or InAl; and forming a layer of InGaAs on the graded layer, the layer of InGaAs comprising about 25 to about 100 at. % In based on total atomic weight of InGa.
1. A semiconducting material, comprising:
a substrate;
a high aluminum content III-V material layer disposed on the substrate, the high aluminum content III-V material layer comprising at least one III element and a V element, the at least one III element comprising Al and being present in an amount of least 50 atomic % (at. %) based on total atomic weight of the at least one III element, and the high aluminum content III-V material layer being partially oxidized to include AlO;
a graded layer of an indium (In) containing III-V material disposed on the high aluminum content III-V material layer, the In containing III-V material being indium-gallium-arsenic (InGaAs) or indium-aluminum-arsenic (InAlAs) and comprising In in an increasing atomic gradient up to 35 at. % based on total atomic weight of InGa or InAl; and
a InGaAs layer disposed on the graded layer, the InGaAs layer comprising about 25 to about 100 at. % In based on total atomic weight of InGa.
2. The semiconducting material of claim 1 , wherein the graded layer has a thickness in a range from about 0.5 to about 1.5 micrometers.