CONTROL OF SEMICONDUCTOR EPITAXY BY APPLICATION OF AN EXTERNAL FIELD

"The quality of semiconductor thin-film grown by vapor phase epitaxy is strongly dependent on the growth conditions. The diffusion of adatoms on the flat surface is largely responsible for the quality of the film. The diffusion rate is directly related tothe bond energy of adatoms. Recent experiments have demonstrated that application of an external field can lead to a change in the microstructure of the film. Properly controlled, this phenomenon could be used to improve the quality of the film. However,a fundamental understanding of the influence of the field is first necessary to achieve this improvement. The goal of the proposed work is, therefore, to establish a precise correlation between the quality of the film and the strength and orientation ofthe external field. First-principle ab initio quantum chemistry and Kinetic Lattice Monte Carlo (KLMC) methods will be used to determine this correlation. Bond energies and activation barriers will be calculated by an ab initio method and KLMCcalculations will be performed to obtain microstructures of the film. Michigan State University will provide expertise in KLMC calculations as well as experimental validation. This technology will be incorporate into CFDRC's code CFD-FILM for modelingsurface morphology in order to enable development and transfer this technology to the semiconductor industry. Successful completion of the proposed project will provide the semiconductor and opto-electronic industry with the necessary tools to produce thinfilms with significantly reduced defects. This will lead to improved quality electronic devices such as: LED's, Laser diodes, VCSELs, pHEMTs, HBTs, and FETs. These devices are used in commercially and militarily important applications such as displays,data storage/retrieval, sensors, electronics, and communications."