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The silicon dioxide (SiO 2 ) on AlGaAs prepared by liquid phase deposition (LPD) at 40 • C has been explored. The LPD-SiO 2 film deposition rate is about 67 nm h −1 for the first hour. The leakage current density is about 1.21 × 10 −6 A cm −2 at 1 MV cm −1 . The interface trap density (D it ) and the flat-band voltage shift ( V FB ) are 1.28 × 10 12 cm −2 eV −1 and 0.5 V, respectively. After rapid thermal annealing in the N 2 ambient at 300 • C for 1 min, the leakage current density, D it , and V FB can be improved to 4.24 × 10 −7 A cm −2 at 1 MV cm −1 , 1.7 × 10 11 cm −2 eV −1 , and 0.2 V, respectively. Finally, this study demonstrates the application of the LPD-SiO 2 film to the AlGaAs/InGaAs pseudomorphic high-electron-mobility transistor.

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We obtain the numerical solutions for a single electron energy level of a hydrogen impurity confined inside an off-center donor in a spherical quantum dot. The energy spectrum of single electron impurity for off-center donor atom subject to screened Coulomb's attractive potential barrier well is presented. Using B-spline finite element method, we generate a complete set of wavefunctions within the central unit cell, and through the perturbation theory, the whole energy spectrum of an impurity at low temperature can be explored. We find that the energy splitting and different related magnetic quantum number m l , i.e., (n, l, m l ) varies with quantum dot size. This is due to the fact that quantum confinement effect lifts the degeneracy which comes from the Coulomb interaction. On the other hand, the phenomena of energy spectrum splitting under this model is an analogous case, considering that degeneracy of hydrogen energy levels in free space has been lifted by an external magnetic field (Zeeman effect).