The research is a renewal of a grant by The National Science Foundation to Professor S. M. Bedair, North Carolina State University, to investigate the potential of laser enhanced metallorganic vapor deposition to selectively deposit epitaxial films of compound semiconductors on gallium silicon substrates. The previous award by the Foundation to Professor Bedair was a Special Creativity Award. During the previous grant several significant accomplishments were made, e.g., establishment of the experimental conditions for selective epitaxy and direct writing of single crystals of gallium arsenide, aluminum gallium arsenide, gallium arsenic phosphide, and indium gallium arsenide on gallium arsenide and silicon substrates, growth of compound semiconductors by laser-enhanced chemical vapor deposition at the lowest reported temperatures (250oC), and growth of superlattices using chemical vapor deposition without gas switching. The research during this continuation period will emphasize the following: thermal processing during laser-enhanced chemical deposition, study of effects of thermal stress on the quality of the films, study of gas dynamics during growth, study of doping behavior and electrical properties of the films, and low temperature deposition, direct laser writing during deposition. The research is relevant to maskless writing and growth of optoelectronic devices, and advanced epitaxial growth of integrated optical and electronic materials. Optoelectronic materials will impact communications and optical processing devices which are important to the economic competitiveness of the United States. Students are receiving excellent training under the grant for careers in research on these vital materials.