Presidential Young Investigator Award: High Speed Optoelectronic Devices and VLSI Structures by Laser Enhanced Epitaxy

该计划将专注于低温，光增强化学气相沉积技术，以实现单晶外延。使用低压汞灯的非选择性光激发，以及使用ArF准分子激光器的选择性外延，将与使用非相干弧灯的快速热处理相结合，在生长过程中快速调节衬底温度。使用这种生长技术研究的两种材料体系包括硅N- i-P-i掺杂超晶格和Si-SixGe1-x应变层超晶格/伪晶层。这些系统将从新颖设备应用的角度进行检查。它们分别是利用N-i-P-i超晶格的可调谐带隙特性进行电调制，以及利用Si-SixGe1-x应变层体系中的布里因区折叠和晶格应变相结合获得直接带隙超晶格的可能性。我们相信光增强CVD技术在竞争的生长技术中具有显著的潜在优势。它不需要像MBE那样的超高真空条件。它允许前体物质的选择性激发，允许更好的晶体质量和更少的污染比等离子体cvd。与MOCVD相比，衬底温度可以降低。综上所述，光增强CVD可以实现具有突变界面和掺杂轮廓的优异异质结构，从而允许使用成分和掺杂超晶格的新型器件应用。

This program will focus on low temperature, photo-enhanced chemical vapor deposition techniques to achieve single crystal epitaxy. Non- selective photo-excitation using a low pressure mercury lamp, as well as selective epitaxy using an ArF excimer laser will be used coupled with rapid thermal processing using incoherent arc lamps to rapidly adjust the substrate temperature during growth. Two materials systems to be studied using this growth technique include silicon N- i-P-i doping superlattices and Si-SixGe1-x strained layer superlattices/pseudomorphic layers. These systems will be examined from the viewpoint of novel device applications. They are, respectively, electroptic modulation using the tunable bandgap properties of N-i-P-i superlattices and the possibility of obtaining direct bandgap superlattices using a combination of Brillouin zone folding and lattice strain in the Si-SixGe1-x strained layer system. We believe a photo-enhanced CVD technique has significant potential advantages over competing growth techniques. It does not require ultra high vacuum conditions as in MBE. It allows selective excitation of precursor species, allowing better crystalline quality with less contamination than plasma-CVD. Substrate temperatures can be lowered compared to MOCVD. In conclusion, excellent heterostructures with abrupt interfaces and doping profiles should be achievable by photo-enhanced CVD to allow novel device applications using compositional and doping superlattices.