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Pure and Al doped nanocrystalline ZnO films have been prepared on Hydrogen terminated Si(100) substrates by nebulized spray pyrolysis. The dependence of the structural, compositional and electrical properties were investigated using XRD, EDX, AFM and spectrophotometer. The X-ray diffraction data coincide well with the pattern of ZnO reported with the Standard Database. Films annealed at higher temperatures show better orientation, as revealed from X-ray diffraction patterns. Annealing the films in air improved the electrical properties. From the I-V characteristics, the nonlinear coefficient α value has been estimated. Reflectance measurements show good reflectance in the IR region for pure ZnO films, and Al doping improved the reflectance values.

Quantum and classical components are blended together in this proposed theoretical model for describing multiple quantum well solar cells (MQWSC) in a p-i-n architecture. The model characteristics are: the use of transfer matrix as a quantum method for finding allowed energies in the coupled quantum wells, the connection of the absorption coefficient in the confined 2D structure to the one in the bulk semiconductor, and the treatment of the whole cell as a pseudo-homogeneous media to determine its reflectance. The resulted model is intended to be a working tool to assess electro-optical properties of MQWSC. Numerical results which relate the performance of the MQWSC to its structure are reported.