A5049917269- Particle accelerators and beam dynamics
- Particle Accelerators and Free-Electron Lasers
- Semiconductor materials and devices
- Electron and X-Ray Spectroscopy Techniques
- Metal and Thin Film Mechanics
- Plasma Diagnostics and Applications
- Photocathodes and Microchannel Plates
- Nuclear Physics and Applications
- Fusion materials and technologies
- Physics of Superconductivity and Magnetism
- Gyrotron and Vacuum Electronics Research
- Superconducting Materials and Applications
- Ga2O3 and related materials
- GaN-based semiconductor devices and materials
- ZnO doping and properties
- Magnetic properties of thin films
- Advancements in Photolithography Techniques
- Magnetic and transport properties of perovskites and related materials
- Advanced Materials Characterization Techniques
- Silicon and Solar Cell Technologies
- Electrostatic Discharge in Electronics
- Electronic and Structural Properties of Oxides
- Hydrogen embrittlement and corrosion behaviors in metals
- Silicon Carbide Semiconductor Technologies
- Diamond and Carbon-based Materials Research
Daresbury Laboratory
1998-2022
Cockcroft Institute
2020-2022
Sci-Tech Daresbury
2020
Science and Technology Facilities Council
2013
Manchester Metropolitan University
2009
The performance of a UHV vessel can be improved with new CERN technology nonevaporable getter (NEG) coating, which is already widely used for accelerator vacuum chambers. Better understanding the processes involved in NEG film deposition, activation, and poisoning should allow optimization engineering properties, are necessary particular application. Ti–Zr–V films were created by magnetron sputtering from single target, morphology dependence on deposition pressure, conditions, substrate...
Electron photoinjectors provide high-brightness electron beams to numerous research applications in physics, chemistry, material, and life sciences. Semiconductor photocathodes are widely used here, as they enable the production of low-emittance with variable charge at high repetition rates. One key figures merit is minimum achievable bunch length. In semiconductor cathodes, this dominated by scattering effects varying penetration depths extracting photons, which leads a characteristic...
The compact linear accelerator for research and applications (CLARA) is an ultrabright electron beam test facility being developed at STFC Daresbury Laboratory. ultimate aim of CLARA to advanced free laser (FEL) schemes that can later be implemented on existing future short-wavelength FELs. In addition, a unique provide high-quality novel concepts ideas in wide range disciplines function as technology demonstrator United Kingdom x-ray FEL facility. built three phases; the first phase, or...
A comparison of the performance nonevaporable getter (NEG) films deposited using two different types targets has been made to find one that best pumping properties. For first time, NEG coating was a preformed Ti-Zr-V alloy target. The film characterization and properties have studied in with commonly used three-wire twisted It demonstrated target produces uniform composition both laterally depth. found be same as Film topography microstructure 5 nm grain sizes were for targets. main result...
An installation for investigation of the electron stimulated desorption (ESD) from both pumping and nonpumping tubular samples was designed built. This allows studying ESD sample sticking probability as a function dose up to about 1023 e−/m2, energy in range 10 eV–6.5 keV, sampling temperature 0–80 °C. Two were investigated: bare Ti–Zr–V coated stainless steels. The yields measured accumulated dose, energy, different NEG coating activation temperatures. effect CO saturated demonstrated first...
In this study, two identical 316LN stainless steel tubular samples, which had previously been polished and vacuum-fired then used for the electron-stimulated desorption (ESD) experiments, were coated with Ti-Zr-Hf-V different morphologies: columnar dense. ESD measurement results after nonevaporable getter (NEG) activation to 150, 180, 250, 350 °C indicated that values yields are significantly (2–20 times) lower than data from our previous study similar coatings on nonvacuum-fired samples....
The ASTeC Vacuum Science Group has an ongoing study for the improvement of nonevaporable getter (NEG) coatings currently used in many accelerators around world. main advantages using NEG are evenly distributed pumping speed, low thermal outgassing rates, and photon-stimulated gas desorption electron-stimulated (ESD). Previously, it was shown that dense coating provides lower ESD compared to a columnar film, but its properties reduced. This paper describes results dual layer where deposited...
MEIS and XPS studies have been conducted for a range of oxygen plasma treated copper samples (and one with Ar plasma), as part study the preparation photocathode surfaces. This procedure was seen to remove hydrocarbon contamination, but left an oxide film whose thickness depended on treatment conditions used. The increase longer time higher RF power levels behaviour characteristic diffusion limited process. Annealing led removal layer by into bulk samples. indicates that where is...
The electron stimulated desorption (ESD) yields of vacuum chamber wall materials are required as one the important input parameters in design systems for particle accelerators and many other where energetic electrons hit walls. In present study, ESD were measured analyzed (a) a function accumulated dose, (b) total amount desorbed gas, (c) energy bombarding. this three separate 316 L stainless steel samples bombarded with up to an dose ∼2 × 1023 e−/m2 at different corresponding energies: 50...
The production of superconducting coatings for radio frequency cavities is a rapidly developing field that should ultimately lead to acceleration gradients greater than those obtained by bulk Nb RF cavities. Optimizing superconducting properties thin-films therefore essential. films were deposited magnetron sputtering in pulsed DC mode onto Si (100) and MgO (100) substrates also high impulse (HiPIMS) (100), MgO and polycrystalline Cu. characterised using scanning electron microscopy, x-ray...
Globally, most recent power electronics converter and device technology has been driven by the unprecedented demand seen within automotive sector [1]. The latter demands converters with near 100% energy efficiency, lightweight, compact reliable. Wide band gap (WBG) semiconductor materials such as GaN 4H-SiC have emerged contenders to replace Si in many applications. Currently, devices based on high electron mobility transistor (HEMT) architecture are limited commercially a maximum of 650 V...
Abstract With the benefits of evenly distributed pumping, low thermal outgassing rate and photon-/electron-/ion stimulated desorption yields, non-evaporable getter (NEG) coating has been widely used in particle accelerators for many years. Our earlier work demonstrated different thickness Ti-Zr-V range 0.1–1 μm affects its pumping properties. In this study, electron (ESD) yields were studied deposited from a twisted target with less than 0.5 μm, while an uncoated sample was also measured as...
The production of superconducting coatings for radio frequency cavities is a rapidly developing field that should ultimately lead to acceleration gradients greater than those obtained by bulk Nb RF cavities. use thin films made from superconductors with thermodynamic critical field, �*�oP�* �o �«�' , allows the possibility multilayer superconductor - insulator (SIS) and also accelerators could operate at temperatures above 2 K typically used. SIS theoretically allow increased gradient due...
Non-evaporable getter (NEG) coating has been used for years in many particle accelerator facilities due to its evenly distributed pumping speed, low thermal outgassing, and photon electron stimulated desorption yields. We have previously demonstrated that quaternary Ti-Zr-Hf-V deposited from an alloy wire the lowest yields, highest sticking probability sorption capacity. In this work, we explore single element targets which are widely available can be produced a form of is easy apply uniform...