CONTROL OF THE SATURATION VALUE OF PLANAR SI DOPING IN ALLNAS LAYERS GROWN BY METALORGANIC CHEMICAL-VAPOR DEPOSITION

We observed a strong correlation between sheet carrier concentration in Si planar-doped AlInAs layers and the flow rate of AsH3 supplied during the doping rhe AlInAs layers were grown by metalorganic chemical vapor deposition and were planar doped by supplying Si2H6 in AsH3 atmosphere. The sheet carrier concentration measured by the van der Pauw method and the sheet Si atom concentration measured by secondary ion mass spectrometry agreed well. Our results can be interpreted on the basic of a previously introduced model taking into account Si incorporation and desorption. We applied this desorption effect to doping control in Si planar-doped AlInAs/GaInAs selectively doped heterostructures. By changing AsH3 flow rate at a given doping time and Si2H6 flow rate, we could control the sheet Si atom concentration and hence the two-dimensional electron gas in the selectively doped heterostructures.