Laser Beam Selected Epitaxy of III-V Compounds

这项研究是美国国家科学基金会向北卡罗来纳州立大学S·M·贝代尔教授提供的资助的延续，目的是研究激光增强金属有机气相沉积在镓硅衬底上选择性沉积化合物半导体外延薄膜的潜力。该基金会此前颁发给贝德代尔教授的奖项是特别创意奖。在上一次赠款期间，取得了几项重大成就，例如，建立了在砷化镓和硅衬底上选择性外延和直接写入砷化镓、砷铝砷、磷化镓和砷化铟单晶的实验条件，通过激光增强化学气相沉积在报告的最低温度(250摄氏度)下生长化合物半导体，以及使用化学气相沉积而不需要气体开关来生长超晶格。在接下来的一段时间里，研究重点将放在以下几个方面：激光增强化学沉积过程中的热处理，热应力对薄膜质量的影响，生长过程中的气体动力学研究，薄膜的掺杂行为和电学性质的研究，以及低温沉积，沉积过程中的直接激光写入。这项研究对光电子器件的无掩模写入和生长，以及集成光电子材料的先进外延生长具有重要意义。光电子材料将影响对美国经济竞争力至关重要的通信和光学处理设备。在这些重要材料的研究工作中，学生们正在接受极好的培训。

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.