Hot Electrons in Metal Films: Injection and Collection

Selected Topics in Electronics and Systems

2009

Recent advances in successful operation of silicon-based devices where transport is dependent on electron magnetic moment, or "spin", could provide a future alternative to CMOS for logic processing. The basics of this spin electronics (Spintronics) technology are discussed and the specific methods necessary for application to silicon are described. Fundamental measurements of spin polarization and spin precession are demonstrated.

Section: Techniques For Spin Injection and Detection In Siliconmentioning

confidence: 99%

Silicon Spintronics

Selected Topics in Electronics and Systems

2009

“…3,4 Tunnel junctions have been used for hot-electron injection from metals into semiconductors for decades. First, they were used in solid-state devices to make ultrafast transistors, 5,6 which mate a tunnel junction to a Schottky diode with a thin base. Later, they served as the basis for a three-terminal microscopy based on the scanning tunneling microscope, known as ballistic electron emission microscopy ͑BEEM͒ and its associated spectroscopy ͑BEES͒.…”

Section: Introductionmentioning

confidence: 99%

Monte Carlo calculations for metal-semiconductor hot-electron injection via tunnel-junction emission

Narayanamurti

2005

Phys. Rev. B

We present a detailed description of a scheme to calculate the injection current for metal-semiconductor systems using tunnel-junction electron emission. We employ a Monte Carlo framework for integrating over initial free-electron states in a metallic emitter and use interfacial scattering at the metal-semiconductor interface as an independent parameter. These results have implications for modeling metal-base transistors and ballistic electron emission microscopy and spectroscopy.

“…Very soon thereafter, Spratt et al [26] showed that a semiconductor collector could be used to realize this device with an Au-Al x O-Al TJ. A schematic band diagram of this device is shown in figure 2.…”

Section: Hot Electron Generation and Collectionmentioning

confidence: 99%

Introduction to spin-polarized ballistic hot electron injection and detection in silicon

Phil. Trans. R. Soc. A.

2011

Ballistic hot electron transport overcomes the well-known problems of conductivity and spin lifetime mismatch that plague spin injection attempts in semiconductors using ferromagnetic ohmic contacts. Through the spin dependence of the mean free path in ferromagnetic thin films, it also provides a means for spin detection after transport. Experimental results using these techniques (consisting of spin precession and spin-valve measurements) with silicon-based devices reveals the exceptionally long spin lifetime and high spin coherence induced by drift-dominated transport in the semiconductor. An appropriate quantitative model that accurately simulates the device characteristics for both undoped and doped spin transport channels is described; it can be used to recover the transit-time distribution from precession measurements and determine the spin current velocity, diffusion constant and spin lifetime, constituting a spin 'HaynesShockley' experiment without time-of-flight techniques. A perspective on the future of these methods is offered as a summary.