CAREER: Synthesis, Microstructure, and Mechanical Behavior of Metallic Thin Films with Nanoscale Growth Twins

Texas A&M Engineering Experiment Station, College Station TX

Investigators

Abstract

TECHNICAL: This project creates a strong foundation for PI to strengthen the lead of his research group in the area of synthesis and mechanical properties of metallic films with nanoscale growth twins nationally and internationally, explore an innovative twin interface induced strengthening mechanism at small length scale, expand his research expertise in the area of mechanical and electrical properties of metal films, and ensure the development of educational plans to become a successful educator. To achieve the research goal, PI plans to explore (1) manipulation of the formation of nanoscale growth twins in polycrystalline metallic films (2) twin interface mediated strengthening and deformation mechanisms at nanometer length scale, (3) deformability of free-standing nanotwinned metallic films under tension and compression, (4) thermal stability of growth twins and evolution of mechanical and electrical properties, and (5) electrical properties of nanotwinned metallic thin films. The research plan will explore innovative strengthening and deformation mechanisms enabled by nanoscale growth twins. The roles of twin interface on strengthening and deformation mechanisms at small length scale are not clear mainly due to a lack of materials with high-density growth twins. The success of the project will lead to a new paradigm to design and fabricate high strength single-phase materials by tailoring nanoscale growth twins. NON-TECHNICAL: High strength, high conductivity Cu films could have dramatic impact on electronic and semiconductor industry, and NEMS/MEMS device. Such high strength nanotwinned Cu films, if widely used in electronic industry, could also impact the development. To achieve the educational goal, PI will (1) collaborate with faculty and students from neighboring minority serving institutions (2) educate and train graduate and undergraduate students on research, including summer research experiences at national laboratories, (3) efficiently interact with high school teachers and students through on-campus NSF-RET programs, (4) prepare graduate and undergraduate students as next generation educators, (5) develop curriculum for undergraduate and graduate students, and (6) develop a website to disseminate research and educational outcome. Research and educational plans are closely integrated to foster a nature process of learning and discovery. The CAREER plan is strengthened by collaborations with Los Alamos National Laboratory, Lawrence Berkeley National Laboratory, and Forschungszentrum Karlsruhe in Germany. The CAREER plan fits very well with departmental long-term goals and institutional vision. The CAREER plan will impact graduate and undergraduate students learning and training through multiple approaches, including active learning and teaching, research experience at national laboratories, etc. The CAREER plan will seek to maximize the dissemination of research outcome in nanomechanics area to a broader group of audience, including minority serving institutions, and high school students. A model is described that may help to prepare students as next generation educators.