GOALI/Spin Electronics: Development of ZnO Based Room Temperature Spintronics

[0224166]该提案是根据21世纪自旋电子学倡议，项目招标NSF 02-036收到的。该提案侧重于研究和开发金属有机化学气相沉积（MOCVD）生长的过渡金属（TM）掺杂ZnO作为稀释磁半导体（DMS）层，并通过工业合作伙伴和政府实验室探索其应用。这种材料提供了高度集成的器件架构以及操纵载流子自旋和电荷的能力的可能性。实际应用要求材料具有高于室温的磁居里温度。虽然理论研究已经确定GaN和ZnO是这方面最有前途的DMS材料，但TM离子在ZnO中的高溶解度、宽带隙（透明）、多功能性和相对较低的生长温度使ZnO成为室温自旋电子学材料的绝佳选择。为了实现他们的目标，他们将专注于：系统研究开发用于生长tm掺杂ZnO薄膜的低压MOCVD技术。最有前途的掺杂物质是V、Co、Ni和Mn，而R-Al2O3是最理想的衬底；协调表征程序使用内部和同步辐射为基础的光谱，成像和衍射技术来表征mocvd生长的tm掺杂ZnO薄膜的化学，电子，结构和磁性；并通过工业合作将ZnO自旋对准层与GaN LED集成在一起，形成在室温下工作的自旋极化注入LED。本研究的成功完成将对稀释磁性半导体自旋电子学的科学认识和实际应用产生重大影响。预计在宽带隙DMS材料中会发现与自旋电子、自旋磁和自旋光集成相关的新现象，从而带来全新的器件和应用。

0224166LuThis proposal was received in response to the Spin Electronics for the 21st Century Initiative, Program Solicitation NSF 02-036. The proposal focuses on the study and development of metalorganic chemical vapor deposition (MOCVD) -grown transition metal (TM) -doped ZnO as a diluted magnetic semiconductor (DMS) layer, and explore its application through industrial collaborators, as well as government labs. This material offers the possibility of highly integrated device architecture along with the ability to manipulate carrier spin as well as charge. Practical application requires that the material have a magnetic Curie temperature above room temperature. While theoretical studies have identified GaN and ZnO as the most promising DMS materials in this regard, the high solubility of TM ions in ZnO, as well as its wide band gap (transparent!) its multifunctionality, and relatively low growth temperature make ZnO an excellent choice of room temperature spintronics material. To achieve their goals, they will focus on: A systematic study to develop low-pressure MOCVD technology for growth of TM-doped ZnO films. The most promising doping species are V, Co, Ni, and Mn, and R-Al2O3 is an optimal substrate; A coordinated characterization program using both in-house and synchrotron radiation based spectroscopic, imaging, and diffractive techniques to characterize the chemical, electronic, structural and magnetic properties of the MOCVD-grown TM-doped ZnO films; and through the industrial collaboration integrate the ZnO spin aligner layers with GaN LEDs to form the spin-polarized injection LED operational at room temperature. The successful completion of the proposed research will have a significant impact on the scientific understanding and practical application of diluted magnetic semiconductor spintronics. It is anticipated that new phenomena related to spin-electronic, spin-magnetic, and spin-optical integration in wide band gap DMS materials will be discovered, leading to fundamentally new devices and applications.