RUI (Collaborative Research): Ion and Radical Beam Tailored Oxide, Nitride and Germanide Electronic Film Materials

这是一个RUI在邻近州立大学的三个物理项目之间的合作研究项目：安吉洛州立大学、塔尔顿州立大学和西南德克萨斯州立大学。该项目侧重于三个主要主题：(1)采用自由基原子束工艺制备ZnO和氮掺杂ZnO的电学和光学性质与应力之间的相关性；(2)制备预测的ZnO- mn和Zn-Co室温透明磁性半导体的可行性；(3)由Pr-Al-O、Gd-Ga-O、Hf-Al-O组成的非晶态或潜在外延绝缘体氧化物合金的介电性能；Pr-Zr-O和La- Hf-O（大多数可能具有氧化氮化和合金依赖的带隙可变性）与磁自旋隧道结构和下一代CMOS栅极应用相关。本文还将对Cu-Ge和Co- Ge薄膜的稳定和表征进行研究。薄膜材料的制备将采用离子束溅射加工策略。该方法是利用单能Ar +或Xe +离子（1 keV）来控制入射薄膜的吸附能（~ 6 eV至~ 20 eV），并改变衬底的入射角来促进薄膜在低温下的动力学生长，无论是否有反射的高能Ar/Xe原子轰击。低能（100 eV）活性（O2 + /N2 +）辅助离子束将与中性热原子自由基进行比较，以促进在降低衬底温度下的最佳氧化（和掺杂氮化）。利用原位低能和/或中性原子自由基来促进反应溅射对于离子束溅射来说是相对独特的，而磁控溅射由于其更高的工作压力而不可能实现。该团队还具有快速热退火和高能（1 MeV）惰性离子混合处理溅射薄膜的能力，以研究非晶沉积金属锗薄膜中锗化物的形成。该项目涉及具有技术相关性的材料科学主题领域的基础研究问题。该项目的一个重要特点是非常重视教育，并将研究与教育相结合。来自这三所大学的本科生将参与研究的多个阶段，其中包括代表性不足的群体的强烈参与。除了离子束溅射，学生将参与快速热处理，电输运研究，离子束分析，扫描电子显微镜与EDS，先进的x射线衍射和荧光分析，磁强计，和光学特性（反射率，FTIR，光致发光）。此外，学生将有机会与对该项目的兴趣的德州中部微电子工业科学家和博士机构研究团队进行合作互动。这三所合作大学的距离足够近，因此可以进行积极的校际团体访问和学生交流，以支持研究。这项研究将鼓励学生考虑在各种材料相关的博士课程中进行研究，或考虑继续接受专业硕士课程的教育。此外，从该项目中获得的广泛的薄膜材料经验将为学生在微电子行业的实习做有益的准备，并加强这一关键行业受过良好教育的学士/硕士毕业生的劳动力储备

This is an RUI collaborative research project among three physics programs at neighboring state universities: Angelo State University, Tarleton State University, and Southwest Texas State Uni-versity. The project focuses on three main topics: (1) correlation between electrical and optical properties and stress in ZnO and nitrogen-doped ZnO fabricated at reduced temperatures using radical atomic beam processing, (2) feasibility of fabricating predicted ZnO-Mn and Zn-Co room temperature transparent magnetic semiconductors, and (3) dielectric properties of select amor-phous or potentially epitaxial insulator oxide alloys consisting of Pr-Al-O, Gd-Ga-O, Hf-Al-O, Pr-Zr-O and La- Hf-O (most with possible oxynitridation and alloy-dependent band gap variabil-ity) relevant for magnetic spin tunneling structures and next-generation CMOS gate applications. A study towards the stabilization and characterization of metastable Ni-incorporated Cu-Ge and Co- Ge thin film crystalline phases will also be included. Thin film materials fabrication will be conducted using ion beam sputter processing strategies. The approach is to implement mono-energetic Ar + or Xe + ions (1 keV) to control incident film adatom energy (between ~ 6 eV to ~ 20 eV), and vary the substrate angle of incidence to promote kinetic film growth at reduced temperatures with and without reflected energetic Ar/Xe atom bombardment. Low energy (100 eV) reactive (O2 + /N2 + ) assist ion beams will be compared with neutral thermal atomic radi-cals to promote optimal oxidation (and dopant nitridation) at reduced substrate temperatures. The implementation of in-situ low energy and/or neutral atomic radical species to promote reactive sputtering is relatively unique for ion beam sputtering and is not possible with magnetron sput-tering due to its higher operating pressure regime. The group also has the capability of processing sputtered films with rapid thermal annealing and high-energy ( 1 MeV) inert ion mixing to study germanide formation in amorphous deposited metal-Ge films. %%% The project addresses fundamental research issues in a topical area of materials science having technological relevance. An important feature of the project is the strong emphasis on education, and the integration of research and education. Undergraduates from all three universities will be involved in multiple phases of the research, with strong participation from underrepresented groups. In addition to ion beam sputtering, students will be involved with rapid thermal process-ing, electrical transport studies, ion beam analysis, scanning electron microscopy with EDS, ad-vanced x-ray diffraction and fluorescence analysis, magnetometry, and optical characterization (reflectivity, FTIR, photoluminescence). In addition, students will have a chance to collabora-tively interact with Central Texas microelectronics industry scientists and doctoral institution re-search teams interested in the project. All three collaborating universities are close enough to permit an active degree of inter-university group visits and student exchanges to support the re-search. The research will encourage students to consider pursuing research at various materials-related doctoral programs, or consider further education in a professional masters program. In addition, the broad thin film materials experience gained from the project will be useful prepara-tion for student internships in the microelectronics industry and strengthening the workforce pool of educated BS/MS graduates for this critical industry.***