Search results for "elastic recoil detection"
showing 10 items of 38 documents
A study of solar thermal absorber stack based on CrAlSiNx/CrAlSiNxOy structure by ion beams
2019
Renewable energies are foreseen as a major energy resource for next generations. Among several energy sources and technologies available, Concentrated Solar Power (CSP) technology has a great potential, but it needs to be optimised, in particular to reduce the costs, with an increase of the operating temperature and long term stability. This goal can be achieved by tailoring the composition and multilayer structure of films. In this work we present and discuss the results obtained from solar absorber coatings based on nitride/oxynitride structures. A four-layer film structure, W/CrAlSiNx(HA)/CrAlSiNxOy(LA)/SiAlOx, was deposited on stainless steel substrates using magnetron sputtering deposi…
Characterization of ALD grown Ti x Al y N and Ti x Al y C thin films
2017
Abstract Atomic layer deposition (ALD) was used to grow Ti x Al y N and Ti x Al y C thin films using trimethylaluminum (TMA), titanium tetrachloride and ammonia as precursors. Deposition temperature was varied between 325 °C and 500 °C. Films were also annealed in vacuum and N 2 -atmosphere at 600–1000 °C. Wide range of characterization methods was used including time-of-flight elastic recoil detection analysis (ToF-ERDA), X-ray diffractometry (XRD), X-ray reflectometry (XRR), Raman spectroscopy, ellipsometry, helium ion microscopy (HIM), atomic force microscopy (AFM) and 4-point probe measurement for resistivity. Deposited films were roughly 100 nm thick and contained mainly desired elemen…
Ordering effects in extreme high-resolution depth profiling with MeV ion beams
2012
Abstract The continuing development of depth profiling with MeV ion beam methods with depth resolutions in the nanometre, and even sub-nanometre, regime implies the resolved depth become comparable with the interatomic spacing. To investigate how short-range ordering influences depth profiles at these resolutions, we have employed a mathematical modelling approach. The radial, g ( r ) and depth distribution, g ( z ) functions were calculated for (1 0 0) surface, random and amorphous Si structures at 300 K produced using molecular dynamics simulations with the EDIP quasi-empirical potential. The results showed that short-range ordering lead to reduction of the scattering yield below the deep…
Low-energy heavy-ion TOF-ERDA setup for quantitative depth profiling of thin films
2008
Abstract Low-energy heavy-ion time-of-flight elastic recoil detection analysis (TOF-ERDA) is becoming a mature technique for accurate characterization of thin films. In combination with a small tandem accelerator (∼2 MV terminal voltage) and beam energies below 20 MeV, it is suitable for routine analysis of key materials in semiconductor technology. In this paper we discuss advantages and drawbacks of low-energy ERDA, compared to high-energy ERDA, in terms of depth and mass resolution, detection efficiency for light elements, sample irradiation damage and quantification accuracy. The results presented are obtained with the time-of-flight telescope recently developed at IMEC. The time-of-fli…
Time-of-flight ERD with a 200mm2 Si3N4 window gas ionization chamber energy detector
2014
Abstract Low energy heavy ion elastic recoil detection work has been carried out in Jyvaskyla since 2009 using home made timing detectors, a silicon energy detector and a timestamping data acquisition setup forming a time-of-flight–energy telescope. In order to improve the mass resolution of the setup a new energy detector was designed to replace the silicon solid state detector, which suffered from radiation damage and had poor resolution for heavy recoils. In this paper the construction and operation of an isobutane filled gas ionization chamber with a 14 × 14 mm 2 100 nm thick silicon nitride window are described. In addition to greatly improved energy resolution for heavy ions, the dete…
Depth resolution optimization for low-energy ERDA
2007
Abstract With the implementation of low-energy time-of-flight Elastic Recoil Detection Analysis (ERDA), routine analysis of thin films with high depth resolution becomes possible. The optimization of the measurement conditions is a key issue for an accurate sample characterization and is normally a compromise among depth resolution, mass resolution and sensitivity, for a given sample. In this work, we focus on the depth resolution optimization, presenting an extensive study of two different materials, SiO 2 and TiN, representative of light and medium mass targets. The film thickness varies between 10 and 50 nm. The samples were measured with different beams ( 35 Cl, 63 Cu, 79 Br and 127 I),…
Time-of-flight telescope for heavy-ion RBS
2007
Abstract This paper describes a time-of-flight (TOF) spectrometer for Heavy-Ion Rutherford Backscattering Spectrometry (HI-RBS) recently installed at IMEC for thin film analysis. The TOF telescope allows the use of ion beams heavier than He, with advantages in terms of depth and mass resolution and sensitivity compared to conventional RBS based on planar Si detectors. The start timing-signal is produced by the secondary electrons emitted from a thin C foil when traversed by a backscattered ion; the electrons are deflected in an electrostatic mirror towards a Micro-channel plate (MCP) assembly which provides a fast timing response. The stop signal is obtained directly from a second MCP assem…
Ion source and low energy beam transport prototyping for a single-ended heavy ion ToF-ERDA facility
2023
We present the status of the ion source and low energy beam transport prototyping activities for a heavy ion time-of-flight elastic recoil detection analysis (ToF-ERDA) equipment, designed to accelerate a flux of 1–10 particle nano-Ampere of 40Ar6-12+ ions to 3–6 MeV energy for depth profiling of light elements. The prototype injector consists of a novel permanent magnet electron cyclotron resonance ion source CUBE-ECRIS with a minimum-B quadrupole field topology, and a 90° permanent magnet dipole with adjustable field strength for charge state selection. We report experimentally measured argon beam currents as a function of the applied microwave power and ion source potential to demonstrat…
Secondary electron flight times and tracks in the carbon foil time pick-up detector
2014
Carbon foil time pick-up detectors used in the time-of-flight measurements of MeV energy ions have been studied in connection to time-of-flight-energy spectrometer used for heavy ion elastic recoil detection analysis. In experimental coincident TOF-E data characteristic halos are observed around light element isobars, and the origin of these halos were studied. The experimental data indicated that these halos originate from single electron events occurring before the electron multiplication in the microchannel plate. By means of electron trajectory simulations, this halo effect is explained to originate from single electron, emitted from the carbon foil, hitting the non-active area of the m…
Studies on atomic layer deposition of IRMOF-8 thin films
2015
Deposition of IRMOF-8 thin films by atomic layer deposition was studied at 260–320 C. Zinc acetate and 2,6-naphthalenedicarboxylic acid were used as the precursors. The as-deposited amorphous films were crystallized in 70% relative humidity at room temperature resulting in an unknown phase with a large unit cell. An autoclave with dimethylformamide as the solvent was used to recrystallize the films into IRMOF-8 as confirmed by grazing incidence x-ray diffraction. The films were further characterized by high temperature x-ray diffraction (HTXRD), field emission scanning electron microscopy, Fourier transform infrared spectroscopy (FTIR), time-of-flight elastic recoil detection analysis (TOF-…