Laser Processing and Characterization of Diamond and Boron Nitride Films and Related Semiconductor and Superconductor Structures

这项赠款支持Jagannadham Kasichainula博士的研究， 北卡罗来纳州州立大学的同事们， 金刚石和氮化硼的激光加工和表征 膜以及相关的半导体和超导体结构。 采用等离子体辅助和 热辅助化学气相沉积（CVD）方法。 采用激光辅助HFCVD去除石墨相 通过用脉冲激光照射蚀刻与金刚石共沉积。 单室原位处理技术也已经被广泛应用。 利用其可以顺序地沉积多层 通过激光烧蚀。 这些方法现在将应用于钻石 在SiC和YBa_2Cu_3O_7高Tc表面上沉积 超导薄膜，以及激光辅助的 金刚石膜上的欧姆接触。 这些电影将是 具有高分辨率和分析透射率的特点 电子显微镜技术。 确定的原子结构 缺陷和接口，一个三步迭代程序将 采用，涉及原子结构计算，图像 模拟，以及模拟与实验的比较 图像. 样品将通过光学特性 技术，如拉曼光谱，和之间的相关性 微观结构、显微硬度和导电性将 被衡量。 %%% 该奖项是在该司的电子材料计划 材料研究。 所支持的研究旨在 金刚石、硼薄膜合成与表征 氮化物，以及金刚石和氮化硼在半导体和 超导体表面 这项研究很重要，因为 独特的机械，电气，光学，热学和化学 金刚石及其相关的氮化硼的特性使它们 适用于耐磨等多种应用的理想材料 涂料和先进的半导体。 对于多晶膜， 当前的关键研究问题是那些微观结构控制， 例如晶粒尺寸和缺陷。 控制这些属性 在薄膜制造中是性能的关键。

This grant supports research by Dr. Jagannadham Kasichainula and co-workers at North Carolina State University which deals with laser processing and characterization of diamond and boron nitride films, and related semiconductor and superconductor structures. Diamond thin films have been synthesized using plasma-assisted and hot filament-assisted chemical vapor deposition (CVD) methods. Laser-assisted HFCVD has been used to remove graphitic phase codeposited with diamond by etching with pulsed laser irradiation. Single chamber in situ processing techniques have also been developed with which multiple layers can be deposited sequentially via laser ablation. These methods will now be applied to diamond deposition on such surfaces as SiC and YBa2Cu3O7 high-Tc superconducting thin films, and to formation of laser-assisted ohmic contacts on diamond films. These films will be characterized by ultrahigh resolution and analytical transmission electron microscopy techniques. To determine atomic structure of defects and interfaces, a three-step iterative procedure will be employed, involving atomic structure calculations, image simulation, and comparison between simulated and experimental images. Samples will be extensively characterized by optical techniques such as Raman spectroscopy, and correlations between microstructure, microhardness, and electrical conductivity will be measured. %%% This award is in the Electronic Materials Program of the Division of Materials Research. The research supported is directed at synthesis and characterization of thin films of diamond, boron nitride, and depositions of diamond and boron nitride on semi- and superconductor surfaces. This research is of importance because the unique mechanical, electrical, optical, thermal, and chemical properties of diamond and its boron nitride relative make them ideal materials for applications as diverse as wear-resistant coatings and advanced semiconductors. For polycrystalline films, key current research issues are those of microstructure control in such areas as grain size and defects. Control of these properties in thin film fabrication is critical to performance.