As spintronics moves from mostly metal-based devices such as GMR/TMR stacks into semiconductors, multi-function materials are needed that incorporate ferromagnetism, semiconducting, and dielectric properties into one. Ferromagnetic semiconductors or so-called diluted magnetic semiconductors (DMS) are examples of such materials. These materials will ease the manufacturing of new spintronic devices as they allow ferromagnetic properties to be "on chip" and in the "front end"; a first step in a spintronic device. Ion implantation of Mn and growth of Mn-doped semiconductors such as Si and GaAs are currently being explored as candidates.
Realizing the potential of spintronics requires advances in our fundamental understanding of spin polarized electron transport through materials and material interfaces at an atomic level. For example, understanding how spin-flip and spin-dependent scattering of electrons is effected by temperature, materials, and material interface properties may help to tailor material interfaces for efficient spin transfer. Two scanning tunneling microscopy (STM) based techniques are employed that allow the quantification and tagging of defect type to scattering mechanism with atomic resolution. In addition, in situ molecular beam epitaxy is utilized for material synthesis and interface preparation.
The atomic structure and thermodynamics behavior of surfaces can yield profound insight into the structure of matter as a whole. No where are the atomic and thermodynamic properties of surfaces more technologically important than in the family of compound or III-V semiconductors (e.g., GaAs, InP, GaN, etc.). These materials are used to fabricate everyday devices such as lasers found in CD players and fiber-optic communications, transistors for cellular phones, direct broadcast satellite TV, and global positioning systems. Fabrication of these devices starts by depositing layers of atoms onto an atomically clean surface until the entire structure is formed. In other words, the fabrication is always occurring at a surface. Thus a deep fundamental knowledge of the surface and its properties may help to further exploit the growth process to produce novel, next-generation devices. Scanning tunneling microscopy (STM), ballistic electron emission microscopy, and electron diffraction are utilized in the research.