Radio frequency readout of electrically detected magnetic resonance in phosphorus-doped silicon MOSFETs

We demonstrate radio frequency (RF) readout of electrically detected magnetic resonance in phosphorus-doped silicon metal-oxide field-effecttransistors (MOSFETs), operated at liquid helium temperatures. For the first time, the Si:P hyperfine lines have been observed using radio frequency reflectometry, which is promising for high-bandwidth operation and possibly time-resolved detection of spin resonance in donor-based semiconductor devices. Here we present the effect of microwave (MW) power and MOSFET biasing conditions on the EDMR signals.Comment: 2 pages, 3 figure

Overlapping-gate architecture for silicon Hall bar MOSFET devices in the low electron density regime

We report the fabrication and study of Hall bar MOSFET devices in which an overlapping-gate architecture allows four-terminal measurements of low-density 2D electron systems, while maintaining a high density at the ohmic contacts. Comparison with devices made using a standard single gate show that measurements can be performed at much lower densities and higher channel resistances, despite a reduced peak mobility. We also observe a voltage threshold shift which we attribute to negative oxide charge, injected during electron-beam lithography processing.Comment: 4 pages, 4 figures, submitted for Applied Physics Letter

Development of nanowire devices with quantum functionalities

Silicon has dominated the microelectronics industry for the last 50 years. With its zero nuclear spin isotope (28Si) and low spin orbit coupling, it is believed that silicon can become an excellent host material for an entirely new generation of devices that operate under the laws of quantum mechanics [1}. Semiconductor nanowires however, offer huge potential as the next building blocks of nano-devices due to their one-dimensional structure and properties [2]. We describe a fabrication process to prepare doped vapor-liquid-solid (VLS) grown silicon nanowire samples in a 2- and 4-terminal measurement setup for electrical characterisation.Comment: 2 pages Optoelectronic and Microelectronic Materials & Devices (COMMAD), 2014 Conferenc

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

Indium Tin Oxide film characterization using the classical Hall effect

We have used the classical Hall effect to electrically characterize Indium Tin Oxide (ITO) films grown by two different techniques on silica substrates. ITO films have the unique property that they can be both electrically conducting (and to be used for a gate electrode for example) as well as optically transparent (at least in the visible part of the spectrum). In the near infrared (NIR) the transmission typically reduces. However, the light absorption can in principle be compensated by growing thinner films.Comment: 2 pages Optoelectronic and Microelectronic Materials & Devices (COMMAD), 2014 Conferenc

Overlapping-gate architecture for silicon Hall bar MOSFET devices in the low electron density and high magnetic field regime

A common issue in low temperature measurements of enhancement-mode metal-oxide-semiconductor (MOS) field-effect transistors (FETs) in the low electron density regime is the high contact resistance dominating the device impedance. In that case a voltage bias applied across the source and drain contact of a Hall bar MOSFET will mostly fall across the contacts (and not across the channel) and therefore magneto-transport measurements become challenging. However, from a physical point of view, the study of MOSFET nanostructures in the low electron density regime is very interesting (impurity limited mobility [1], carrier interactions [2,3] and spin-dependent transport [4]) and it is therefore important to come up with solutions [5,6] that work around the problem of a high contact resistance in such devices (c.f. Fig. 1 (a)).Comment: 3 page