A New Heterostructure for 2DEG System with a Si Atomic-Planar-Doped AlAs-GaAs-AlAs Quantum Well Structure Grown by MBE

Using Si atomic-planar-doping technology, a new heterostructure, called “Planar-Doped Quantum Well (PD-QW) Heterostructure”, which has a single Si-doped Ga plane with sheet concentration of 0.6–4 ×10 12 cm -2 in an AlAs-GaAs-AlAs quantum well structure as a 2DEG supplying layer was developed. It exhibited 2DEG mobility of 8.7 ×10 4 cm 2 /Vs at 77 K with sheet concentration of 1.0 ×10 12 cm -2 , in addition to much reduced persistent photoconductivity at low temperatures. The sheet resistivity of the 2DEG layer in this material (about 70 Ω/ at 77 K) is the lowest observed so far in selectively doped single-interface heterostructures.