Low temperature transport on surface conducting diamond

Magneto-transport measurements were performed on surface conducting hydrogen-terminated diamond (100) hall bars at temperatures between 0.1-5 K in magnetic fields up to 8T.Comment: 2 pages Optoelectronic and Microelectronic Materials & Devices (COMMAD), 2012 Conferenc

Surface transfer doping of diamond with a molecular heterojunction

Surface conductivity and C1s core level measurements were employed to show that surface transfer doping of hydrogen-terminated diamond C(100) can be achieved with a molecular heterojunction formed with C60F48 and an intralayer of zinc-tetraphenylporphyrin. Measurement of the shift in the diamond Fermi energy shows that the zinc-tetraphenylporphyrin (ZnTPP) layer modifies the C60F48–diamond interaction, modulating the extent of charge transfer between the diamond and the fluorofullerene. In contrast to the case of C60F48 acceptors, the presence of a ZnTPP layer prevents the formation of air-induced surface conductivity, showing that the intralayer acts to selectively separate these two doping channels

Silicon carbide, v.2: power devices and sensors

Silicon Carbide - this easy to manufacture compound of silicon and carbon is said to be THE emerging material for applications in electronics. High thermal conductivity, high electric field breakdown strength and high maximum current density make it most promising for high-powered semiconductor devices. Apart from applications in power electronics, sensors, and NEMS, SiC has recently gained new interest as a substrate material for the manufacture of controlled graphene. SiC and graphene research is oriented towards end markets and has high impact on areas of rapidly growing interest like elec

Attosecond-fast internal photoemission

International audienceThe photoelectric effect has a sister process relevant in optoelectronics called internal photoemission1,2,3. Here an electron is photoemitted from a metal into a semiconductor4,5. While the photoelectric effect takes place within less than 100 attoseconds (1 as = 10−18 seconds)6,7, the attosecond timescale has so far not been measured for internal photoemission. Based on the new method CHArge transfer time MEasurement via Laser pulse duration-dependent saturation fluEnce determinatiON—CHAMELEON—we show that the atomically thin semimetal graphene coupled to bulk silicon carbide, forming a Schottky junction, allows charge transfer times as fast as (300 ± 200) as. These results are supported by a simple quantum mechanical model simulation. With the obtained cut-off bandwidth of 3.3 PHz (1 PHz = 1015 Hz) for the charge transfer rate, this semimetal/semiconductor interface represents a functional solid-state interface offering the speed and design space required for future light-wave signal processing

Photoemission study of the Al-Sb(111) interface

We have studied the interface formation between Sb(111) surfaces and evaporated aluminum with photo emission using synchrotron radiation. Energy distribution curves were measured from the Al 2p and Sb 4d core levels and from the valence band. A curve-fitting procedure was applied to the core-level spectra in order to decompose the peaks into individual components. A model calculation was performed to explain the intensity variation of the different Al 2p components. We show that a two-dimensional layer of AlSb is formed and that Al clusters grow on top of AlSb as soon as a fraction of a mono layer of AlSb is present. This also explains the behavior of the Sb 4d integrated peak areas and of the valence-band energy distribution curves. Finally, partial-yield spectra have been measured in order to assess the AlSb formation and to study the Al 2p exciton