Superlattice Materials, Sub-band Structure

From the appearance of superlattice and quantum well materials of GaAs / AlGaAs semiconductor to these days, study of physical character and film growth techniques of microstructure has advanced rapidly. Especially for the superlattice of GaAs/AlGaAs materials because of its growth is relatively easy and can be controlled. Superlattice materials have many special characters that general semiconductor materials do not have. Because of this point, superlattice and quantum well materials have wide applied prospects. They have become a very active investigative domain in semiconductor physics, material science, microelectronics, and optoelectronics.There have already been many methods to calculate the energy levels of two-dimensional structures. In this paper, we present a new model on calculating electron states unconfined above barriers in a GaAs/AlGaAs superlattice structure. Which is from the view of electron waving, the reflection and interference of electron wave at the interface of superlattice were accounted for. And the calculated energy levels of the conduction states agree well with the measured ones in our experiment.The GaAs / AlGaAs quantum well material made in MBE have been manufactured and analyzed by photoluminescence. Several peak on the photoluminescence spectrum were observed. The calculation results are basically in agreement with the measured ones. And we calculated the breadth of the subband in quantum well structure. This paper includes following parts.Chapter one introduces the research of superlattice and quantum well materials in the near years. And it gives basic theory and basic quality of superlattice and quantum well materials.Chapter two introduces the growth techniques of superlattice and quantum well materials, the principle of molecular beam epitaxy, the growth mechanism of GaAs / AlGaAs quantum well, manufacture of sample and measure method of sample.Chapter three analyses Photoluminescence spectra of the GaAs/AlGaAs...