Dual-Plasma Co-Deposition of Mixed Phase Thin Film Materials

技术：本项目研究非晶/纳米晶(a/nc-Si：H)混合相薄膜的生长和表征。该方法利用双等离子体共沉积过程，在上游流动管式反应器中产生一种类型的纳米晶体颗粒，然后将其注入第二个电容耦合的等离子体沉积系统，在该系统中生长周围的半导体或绝缘材料。为了获得用于光伏和电子应用的a/nc-Si：H薄膜的性能，我们将研究与先前工作相关的材料科学问题，即纳米晶夹杂物的临界浓度会导致a/nc-Si：H薄膜中的缺陷密度降低。混合相a/nc-Si：H将作为一种潜在的“种子材料”用于后沉积形成微晶硅薄膜，无论是通过低温退火法还是场助晶化法。单独控制硅纳米晶体和周围a-Si：H的性质的能力使得能够合成电子质量较差但具有潜在的高氢扩散系数的多孔a/nc-Si：H薄膜，这些薄膜可以用作储氢材料。非技术性：该项目解决了具有高度技术相关性的电子/光子材料科学的热门领域的基础研究问题。研究和教育活动将与研究生和本科生参与研究计划相结合。该项目还涉及正式和非正式的科学教育以及代表人数不足的群体的融合。PI参与了威斯康星州美洲原住民学院工程学学士学位预科课程的开发项目，并将接待来自Monmenie Nation部落的夏季研究高中和本科生。外联活动包括与明尼苏达州科学博物馆合作开发展览，向广大公众解释纳米技术的前景和挑战。少年派也是一本科普书籍(超级英雄物理学)的作者，经常给普通公众讲课。

Technical: This project addresses growth and characterization of amorphous/nanocrystalline (a/nc-Si:H) mixed-phase thin films. The approach utilizes a dual-plasma co-deposition process which produces one type of nanocrystalline particles in an upstream flow-through tube reactor, which are then injected into a second, capacitively-coupled plasma deposition system in which the surrounding semiconductor or insulating material is grown. In order to achieve a/nc-Si:H film properties for photovoltaic and electronic applications, materials science issues underlying previous work showing that a critical concentration of nanocrystalline inclusions leads to lower defect densities in the a/nc-Si:H film will be investigated. The mixed phase a/nc-Si:H will be studied as a potential "seed material" for post-deposition formation of microcrystalline silicon thin films, by either low-temperature annealing or field-assisted crystallization. The ability to separately control the properties of the silicon nanocrystals and the surrounding a-Si:H enables synthesis of porous a/nc-Si:H films of poor electronic quality, but with potentially high hydrogen diffusion coefficients that may serve as hydrogen storage materials.Non-technical: The project addresses basic research issues in a topical area of electronic/photonic materials science with high technological relevance. Research and educational activities will be integrated with involvement of both graduate and undergraduates in the research program. The project also addresses formal and informal science education and integration of underrepresented groups. The PI participates in a program to develop a pre-baccalaureate program in Engineering at the Native-American College of Menomenie Nation in Wisconsin, and will host summer research high school and undergraduate students from the Menomenie Nation tribe. Outreach activities include collaboration with the Science Museum of Minnesota on the development of exhibits explaining the prospects and challenges of nanotechnology to a broad public. The PI is also the author of a popular science book (The Physics of Superheroes) and frequently gives lectures to the general public.