Armando Luches

• Retired at University of Salento

Lasers are widely used for material processing (cutting, drilling, cleaning, film deposition, etc.). A recent application is for nanoparticle fabrication. Pulsed laser ablation is by far the fastest and clean method to fabricate nanoparticles directly from bulk targets. For this purpose, target ablation is performed in vacuum, in gas atmosphere, or...

For the first time the intensity of the electric and magnetic field in the range of electrical power supply and power transmission lines (50 Hz) and in the range of radio-television broadcasting and telecommunications (100 kHz-3 GHz) was measured in occupational sites and power plants of the city of Gjirocastër, Albania, and its surroundings. The i...

Metal oxide sensors with active Fe2O3 and CoFe2O4 nanoparticle arrays were studied. Sensing nanoparticle films from 1, 2, 4 or 7 monolayers were deposited by Langmuir-Blodgett technique. Sensors are formed on the alumina substrates equipped with heating meander. Langmuir-Blodgett layers were heated or UV irradiated to remove the insulating surfacta...

The reactive pulsed laser deposition (RPLD) based on a KrF laser was used for photon synthesis of nanometric iron and chromium oxides films. RPLD allows controlling the thickness and stoichiometry of deposits with definite band gap. So RPLD was used for synthesizing nanometric iron and chromium oxides films for thermo-photo-chemical sensors. We com...

The promising results obtained with the MAPLE-deposition of nanostructured thin films, to be used in different fields, are reviewed. Nanoparticles (TiO2, SnO2, CdS) and nanorods (TiO2) with well defined dimensions were suspended in appropriate solvents (distilled water, toluene) with low concentration (1wt% or less). The solutions were flash frozen...

A poly-(3-hexylthiophene) (P3HT)/[6,6]-phenyl-C-61-butyric-acid-methyl-ester (PCBM) bilayer structure has been realized by single step matrix-assisted pulsed laser evaporation (ss-MAPLE) technique using the same solvent for both the polymers under vacuum conditions. Our ss-MAPLE procedure allows the fabrication of polymeric multilayer device stacks...

A poly-(3-hexylthiophene) (P3HT) / [6.6]-phenyl-C61-butyric-acid-methyl-ester (PCBM) bilayer structure has been realized by single step matrix-assisted pulsed laser evaporation (ss-MAPLE) technique using the same solvent for both the polymers under vacuum conditions. Our ss-MAPLE procedure allows the fabrication of polymeric multilayer device stack...

A polymeric poly (3-hexylthiophene) (P3HT)/[6,6]-phenyl-C61-butyric acid methyl ester (PCBM) bilayer structure has been realized, for the first time, by the Matrix-assisted pulsed laser evaporation (MAPLE) technique. Our procedure is based on a single step process in vacuum conditions and uses the same solvent for both the polymers forming the bila...

Metal oxide sensors with active films from Fe2O3 and CoFe2O4 hexagonally assembled nanoparticle (NP) arrays were studied. NPs were synthesized by high-temperature solution phase reaction. Sensing NP layers were deposited by Langmuir–Blodgett (LB) technique. LB layers were characterized by XRD, SEM and magnetic measurements. NPs are monodomain and s...

Matrix-Assisted Pulsed Laser Evaporation (MAPLE) technique was used to deposit films of Poly(9,9-dioctylfluorene) – PFO and Methoxy Ge Triphenylcorrole [Ge(TPC)OCH3]. The PFO was dissolved in different matrices, like chloroform-CHCl3, tetrahydrofuran – THF and toluene with a 0.5 wt % concentration, while Ge(TPC)OCH3 was diluted in THF with a concen...

The unexpected presence of agglomerates in polymer films deposited by the Matrix Assisted Pulsed Laser Evaporation (MAPLE) technique is discussed. Many experimental and theoretical works suggest that the simple model of individual molecule evaporation must be abandoned. Solute concentration, boiling temperature and vapor pressure of solvents, laser...

Chemically synthesized brookite titanium dioxide (TiO2) nanorods with average diameter and length dimensions of 3–4nm and 35–50nm, respectively, were deposited by the matrix-assisted pulsed laser evaporation technique. Atoluene nanorod solution was frozen at the liquid-nitrogen temperature and irradiated with a KrF excimer laser (λ=248nm, τ=20ns) a...

The matrix-assisted pulsed laser evaporation (MAPLE) technique offers an efficient mechanism to transfer soft materials from the condensed to the vapor phase, preserving the versatility, ease of use and high deposition rates of the pulsed laser deposition (PLD) technique. The materials of interest (polymers, biological cells, proteins, …) are dilut...

Titanium dioxide (TiO2) nanorods in the brookite phase, with average dimensions of 3–4nm × 20–50nm, were synthesized by a wet-chemical aminolysis route and used as precursors for thin films that were deposited by the matrix-assisted pulsed laser evaporation (MAPLE) technique. Ananorod solution in toluene (0.016wt% TiO2) was frozen at the liquid-nit...

In this paper we report on the growth and structural characterization of very thin (20 nm) Cr-doped ITO films, deposited at room temperature by double-target pulsed laser ablation on amorphous silica substrates. The role of Cr atoms in the ITO matrix is carefully investigated with increasing doping content by transmission electron microscopy (TEM)....

Pulsed laser deposition (PLD) is at present one of the most interesting technique for thin film deposition. In the PLD process a film is formed by ablating a solid target with energetic laser pulses and collecting the material of interest on a substrate placed a few cm from the target. According to its ability to carry the stoichiometry from the ta...

Various kinds of zinc oxide (ZnO) nanostructures, such as columns, pencils, hexagonal pyramids, hexagonal hierarchical structures, as well as smooth and rough films, were grown by pulsed laser deposition using KrF and ArF excimer lasers, without use of any catalyst. ZnO films were deposited at substrate temperatures from 500 to 700°C and oxygen bac...

Titanium carbide films were deposited on silicon wafers by laser reactive ablation. A pure titanium target placed inside a methane (CH4) atmosphere was irradiated by a XeCl excimer laser with a fluence of 5 J/cm2 and a repetition rate of 8 Hz. Experiments were performed at different values of the ambient pressure in order to investigate the influen...

The effects of pulsed electron beam irradiation (pulse width 50 ns FWHM, electron eneries from 15 to 30 keV and current density in the range of 100 to 2300 A/cm ² ) on Al-Pb systemsprepared by vacuum evaporation of Pb layers from 500 Å to 2000 Å in thickness over Al single crystals have been investigated by Rutherford backscattering (RBS) and scann...

In the present work a novel approach to suicide and nitride formation on the surface of silicon single crystals wafers is reported. The compound growth occurs directly in the place of interest as a result of a laser promoted chemical reaction. Results indicate that it is possible to obtain a titanium nitride layer superimposed on a titanium suicide...

In this paper we report on the effects of the insertion of Cr atoms on the electrical and optical properties of indium tin oxide (ITO) films to be used as electrodes in spin-polarized light-emitting devices. ITO films and ITO(80 nm)/Cr-doped ITO(20 nm) bilayers and Cr-doped ITO films with a thickness of 20 nm were grown by pulsed ArF excimer laser...

In the period 2005-2006 a survey on natural radioactivity in about 500 schools located in south-east Italy (the Salento peninsula, province of Lecce) was carried out. In particular average radon concentration and average absorbed dose rate in air due to gamma radiation have been assessed by using solid state nuclear track detectors (SSNTD) and elec...

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

The structural, electrical, and optical characteristics of nanometric Fe2O3−x films fabricated on 〈100〉 Si and SiO2 substrates by ablating an iron target with a KrF excimer laser in low pressure (0.05–1.0 Pa) O2 atmosphere are reported. The thickness of films fabricated with 4000 laser pulses is ∼ 80 nm for samples deposited at the lowest pressure...

Thin films of chromium oxides were deposited on Si substrates by KrF laser ablation of a chromium target in O2 atmosphere (0.05-5.0 Pa). Films exhibit semiconducting properties with band gap increasing (0.32-0.71 eV) with increasing pressure from 0.05 to 1.0 Pa. The largest values of the thermoelectromotive force coefficient S (~3.5-4.5 mV/K) were...

Matrix-assisted pulsed laser evaporation (MAPLE) is an evolution of the pulsed laser deposition (PLD) technique. MAPLE preserves the advantages of the PLD technique (versatility, ease of use, high deposition rates) but in addition offers a gentle mechanism to transfer easy-to-decompose materials from the condensed phase into the vapor phase. The ma...

The matrix assisted pulsed laser evaporation (MAPLE) technique has been used for the deposition of metal dioxide (TiO2, SnO2) nanoparticle thin films for gas sensor applications. For this purpose, colloidal metal dioxide nanoparticles were diluted in volatile solvents, the solution was frozen at the liquid nitrogen temperature and irradiated with a...

Two methods were used for the deposition of thin films and layers: pulsed laser deposition (PLD) and laser-induced film transfer (LIFT). The first one was based on using KrF laser radiation. Thin films and layers were deposited by KrF laser ablation of CrSi2 and beta-FeSi2 targets with the aim to obtain silicide layers with narrow band gap for sens...

We report on the potentiality of the Matrix-Assisted Pulsed Laser Evaporation (MAPLE) technique for the deposition of thin films of colloidal nanoparticles to be used for gas sensors based on electrical transduction mechanisms. The MAPLE technique seems very promising, since it permits a good thickness control even on rough substrates, generally us...

Methoxy Ge Triphenylcorrole [Ge(TPC)OCH3] has been recently synthesized and deposited as thin film by the Matrix Assisted Pulsed Laser Evaporation (MAPLE) technique. In the last few years, corroles have been the object of an increasing number of studies and MAPLE technique seems to be a very promising deposition method for organic and polymeric fil...

The structure and morphology of chromium disilicide (CrSi2) nanometric films grown on 〈1 0 0〉 silicon substrates both at room temperature (RT) and at 740 K by pulsed laser ablation are reported. A pure CrSi2 crystal target was ablated with a KrF excimer laser in vacuum (∼3 × 10−5 Pa). Morphological and structural properties of the deposited films w...

Thin films were deposited by KrF laser ablation of CrSi2 and β-FeSi2 targets with the aim to obtain silicide thin films and layers with narrow band gap for sensor applications. The CrSi2-based films exhibit both semiconductor and metal properties, depending on the deposition conditions. Thus, the film of d≅40nm thick, deposited on Si at 740K, prese...

Narrow band gap iron oxide semiconductor films were grown with the laser chemical vapour deposition (LCVD) and reactive pulsed laser deposition (RPLD) techniques. For LCVD, 10 and 18 nm thick films, with composition Fe2O3-x ( 0 <= x <= 1), were deposited from iron carbonyl vapours with an Ar+ laser. Their band gap (E-g) results were of 0.46 eV and...

We report on the growth and characterization of gold nitride thin films on Si 〈1 0 0〉 substrates at room temperature by reactive pulsed laser ablation. A pure (99.95%) Au target was ablated with KrF excimer laser pulses in nitrogen containing atmosphere (N2 or NH3). The gas ambient pressure was varied in the range 0.1–100 Pa. The morphology of the...

Different photo-assisted techniques were employed for chromium disilicide (CrSi2) semiconductor film fabrication. Flash evaporation of CrSi2 powder on the Si substrate heated to ∼740 K leads to the formation (according to XRD study) of amorphous films. Post-annealing at 920 K leads to the formation of polycrystalline CrSi2 phase. Crystallization is...

This chapter reviews the work done in our laboratory and others on synthesis and deposition of thin films of metal nitrides, using the reactive pulsed laser ablation (RPLD) technique. In particular, thin films deposition of transition-metal nitride e.g. TiN and VN, aluminum AlN and boron nitride BN films are detailed. The characteristics of the fab...

Er-doped oxyfluoride silicate thin films were deposited using pulsed laser deposition. The target glass composition was 65SiO2– 3Al2O3–12Na2O–10PbF3–10LaF3 (in mol%) + 1Er2O3 (in wt.%). Irradiations were performed using an ArF excimer laser in a dynamic flow of oxygen of pressure 5 Pa. The laser fluence at the target surface was 2 J/cm2. Films were...

FexNi100−x nanometric films were deposited on SiO2/Si substrates at room temperature using the pulsed laser deposition technique. The targets were Fe–Ni amorphous magnetic foils with composition Fe50Ni50, Fe35Ni65 and Fe22Ni78. Morphological and structural properties of the deposited films were investigated using scanning electron microscopy, Ruthe...

Two laser-based methods were used for the deposition of narrow band gap semiconductor films based on iron oxides. The first one is laser chemical vapor deposition (LCVD) from iron carbonyl Fe(CO)5 vapors using Ar+ laser radiation. The width of the band gap of the films depends on the film thickness and the applied electrical field. The film thickne...

Poly(9,9-dioctylfluorene) (PF8) thin films have been deposited by matrix-assisted pulsed laser evaporation (MAPLE) using a KrF excimer laser. The influence of the laser fluence (50–500 mJ/cm2) and the nature of the solvent (chloroform, toluene, tetrahydrofuran) on the films properties have been studied. The chemical composition of the deposited fil...

Er-doped silicate thin films were deposited by the pulsed laser deposition technique, starting from an Er-doped silicate glass of composition: 65%SiO 2 - 3%Al2O3, - 11%Na2O - 10%PbF 3 - 10%LaF3 - 1%ErF3. The irradiations were performed with an ArF excimer laser (pulse length - 30 ns) in a dynamic flow of oxygen at a pressure of 5 Pa. The laser flue...

Magnetic films were deposited on oxidized Si by KrF laser ablation of amorphous ribbons (composition Fe60Ni20B20, Fe64−xNbxCo21B15 with x=0–5 and Fe73.5−xNixCu1Nb3Si13.5B9 with x=0–40). The deposited films are amorphous. Deviation from stoichiometry is low. The magnetization motion damping parameter λ and magnetization of the films were obtained fr...

Multicomponent magnetic alloy targets were ablated in vacuum with a XeCl excimer laser at three different fluences. The ablated material was collected onto unheated silicon substrates placed at different angles with respect to the target normal at the incident laser spot. Film composition was inferred by Rutherford backscattering spectrometry analy...

We report experimental results obtained for electrical and structural characteristics of yttria-stabilised zirconia (YSZ) thin films deposited by pulsed laser deposition (PLD) on Si substrates at room temperature. Some samples were submitted to thermal treatments in different ambient atmospheres (vacuum, N2 and O2) at a moderate temperature. The ef...

Co and Fe-based alloy films were deposited and studied as perspective materials for the development of fast magnetic sensors. Pulsed laser ablation deposition (PLD) was used as an appropriate technique to fabricate thin films preserving the stoichiomeUy ofthe complex bulk materials. Co67Cr7Fe4SiB14, Fe75Nb3Cu1Si12B9, Fe40Ni40B20 and FexNi1-x (x=22,...

The laser-induced modifications in two kinds of glass–ceramics (GCs) with composition TiO2–SiO2 (Sitall ST-50) and Li2O–SiO2 (Fotoform) were investigated for fabricating optical elements. The laser-induced change of refractive index and surface relief constituted the first step of this task. The second stage was a chemical processing including ion...

In this paper the microstructural characterisation of yttria-stabilised zirconia (YSZ) thin films deposited by laser ablation is reported for the as-deposited sample as well as for samples submitted to thermal treatments in different atmospheres (vacuum, N2 and O2) at a moderate temperature (500 °C). Results obtained by different characterisation t...

Giant magnetoresistance (GMR) is often studied in multilayers (MLs) composed of mutually immiscible pairs of metals. Low miscibility is expected also in Fe/W and Co/W couples where the heat of compound formation is ΔH ≈ 0. Therefore, the GMR in these types of MLs was studied in this work. The MLs were UHV e-beam deposited onto Si, number of periods...

In this work reactive pulsed laser deposition of molybdenum- and tungsten-nitride thin films is investigated. Metallic targets were ablated in low-pressure (1, 10 and 100 Pa) nitrogen atmosphere by KrF excimer laser pulses (fluence ∼6.5 J/cm2). Films were deposited on silicon wafers heated to ∼25, 250 and 500 °C. The characteristics of the films st...

We report on the deposition of thin titanium carbide films on 60 mm and 100 mm Si wafers by KrF laser ablation of titanium targets in low-pressure (0.1 Pa) CH{4} and C{2}H{2} atmospheres, and on their characterization. The targets were titanium foils (purity 99.6%). Si (111) wafers, 60 and 100 mm in diameter, were used as substrates. Film character...

Co67Cr7Fe4Si8B14 magnetic alloy and Cd25Mn25Te50 semimagnetic semiconductor targets were ablated in vacuum with a XeCl excimer laser at different fluences. The ejected material was collected onto unheated silicon substrates at different angles with respect to the target normal. Compositional investigations were performed on the deposited films. In...

Magnetic films were prepared by pulsed laser ablation of amorphous magnetic ribbons (composition Co67Cr7Fe4Si8B14, Fe73.5Nb3Cu1Si13.5B9, and Fe40Ni40B20) and permalloy foils (composition FexNi1-x with x=22,50). Depositions were performed in a vacuum of (2–4)10-5Pa by KrF excimer laser pulses at fluences of between 2 and 7Jcm2. Films were deposited...

An overview on the laser induced diffusion in metallic multilayers (MLs) is given. The method of measurement is illustrated on the studies of Co/Ag bilayers, trilayers and Fe/W and Co/W multilayers for magnetoresistance sensors and of W/Si MLs for X-ray mirrors. Pulsed excimer XeCl and KrF lasers with 30 nm pulses were used. The main advantage of p...

Magnetic films were prepared by pulsed KrF excimer laser ablation of amorphous magnetic ribbons and permalloy foils in vacuum of (2–4)×10−5Pa. Films were analysed by XRD, RBS, EDX and FMR. The films deposited from ribbons are amorphous, permalloy films have the grain size of approximately 5nm. Fe and Fe+Ni rich films have low magnetization motion d...

Targets of Co67Cr7Fe4Si8B 14 magnetic alloy were aoiated in vacuum with an XeCl laser at different fluences ranging from 2.5 to 7 J/cm2. The ablated material was collected onto unheated silicon substrates placed at different angles with respect to the normal of the target at the incident laser spot. Film composition was inferred by Rutherford backs...

Colloidal Co particles of 11 nm diameter were deposited on Si substrate by spin coating and/or casting in magnetic field. A perpendicular magnetic field varying along the diagonal of the substrate was also applied. The samples were analyzed by transmission electron microscopy (TEM), field emission gun scanning electron microscopy (SEM-FEG), atomic...

Pr3+-doped chalcogenide glass (GeS2-Ga2S3-CsI) targets were ablated in vacuum (1x10-5 Pa) by XeCl laser pulses. The deposited films were plane, smooth, well adhesive to the substrate and with a composition close to the target one. The film thickness ranged from approximately 500 nm to approximately 2000 nm. The transmittance and reflectance of the...

We report on the deposition of thin transition metal nitride (TMN) films by ablating Mo, Ta, V and W targets in low-pressure (1, 10 and 100 Pa) nitrogen atmosphere by KrF excimer laser pulses, and on their characterization. The targets were foils of high purity (99.8%). 3" Si(111) wafers wre used as substrates. Film characteristics (composition, cr...

Cd1−xMnxTe films (0.5–0.6 μm) were deposited on sapphire and silicon substrates by XeCl laser ablation of targets with different Mn content (x=0.05, 0.36 and 0.43). Energy dispersive spectroscopy and optical transmission measurements in the 200–3500 nm range were performed to evaluate the film composition and band-gap energy. The film stoichiometry...

Magnetic films and multilayers were prepared by pulsed laser ablation of Co- and Fe-based amorphous magnetic ribbons with compositions Co67Cr7Fe4Si8B14 and Fe73.5Nb3Cu1Si13.5B9, respectively. Targets were ablated in vacuum (∼10−5 Pa) by KrF excimer laser pulses at fluences from 3 to 7 J/cm2. Films were deposited on oxidized silicon wafers, placed 8...

We report on the deposition of thin Yttria-stabilized zirconia (YSZ) films and TiN/YSZ bilayers on Si substrates at room temperature by pulsed KrF excimer laser ablation deposition (PLD). YSZ films were deposited onto (100) Si substrates by ablating an YSZ target in vacuum and in low-pressure oxygen atmosphere. TiN/YSZ/Si bilayers were deposited in...

This paper describes the optical properties of praseodymium-doped chalcogenide (GeS 2 ±Ga 2 S 3 ±CsI) thin ®lms deposited by the pulsed laser deposition (PLD) technique using XeCl (308 nm) and KrF (248 nm) excimer lasers. Optical transmission and re¯ection spectra, at normal incidence, were recorded in the 200±2500 nm spectral region. The optical c...

The interface reactions in Co/W multilayers (ML) with Co thickness of 1 and 2nm and W thickness of 1, 2 and 5nm in as-deposited state and under KrF laser irradiation with fluences F=50–200mJ/cm2 were studied by different X-ray methods. Superlattice satellites around W (110) direction were found in as-deposited and irradiated multilayers. The layere...

SiO2 (silica) and ITO (indium tin oxide) films, SiO2/ITO bilayers and multilayers and Pr3+-doped chalcogenide glass films were deposited by excimer laser ( lambda = 308, 248 and 193 nm) ablation. Dense, stoichiometric SiO2 films, almost droplet-free and with low surface roughness (<5 nm) were deposited with the ArF laser. By using the XeCl laser, I...

Silica, ITO, chalcogenide glass films and multilayers were deposited by excimer laser ablation deposition. Investigations show that good quality stoichiometric silica films can be deposited on substrates at room temperature by ArF laser ablation of SiO in O2 atmosphere. Surface roughness can be kept low (approximately 5 nm). Low- absorbance and low...

Thermal stability and intermixing studies are of primary importance for diverse applications of layered structures and multilayers (MLs). Especially if the thickness of layers is in the nm range, MLs are of great interest for diffusion studies because of small diffusion distances and high number of interfaces. In the paper the intermixing measureme...

Praseodymium-doped GeS2–Ga2S3–CsI thin films were prepared by the pulsed laser deposition (PLD) technique. We ablated chalcogenide glass, Pr3+-doped, targets in vacuum with XeCl laser pulses (308 nm). The films were deposited on microscope slide glass substrates at room temperature. Film characteristics were investigated by many different technique...

We report on the deposition of thin vanadium nitride films by ablating vanadium targets in low-pressure N2 atmosphere, and on their characterization. The targets were vanadium foils (purity 99.8%). 3in. Si(111) wafers were used as substrates. Film characteristics (composition and crystalline structure) were studied as a function of N2 pressure (0.5...

The interface reactions in (1 nm Fe/x nm W) and (2 nm Fe/x nm W) multilayers (x=1, 2, 5 and 7) with 5 or 10 periods in as-deposited state and under KrF laser irradiation with fluences, F=0.05–0.25 J cm−2 and 1 or 10 pulses were studied by X-ray diffraction (XRD), grazing incidence (GI) XRD, X-ray reflectivity, GI X-ray diffuse scattering and cross-...

Ag/Co bilayers and Co/Ag/Co trilayers were studied in order to extend our previous results on the excimer laser-induced grain boundary diffusion in Ag/Co layered structures, used in giant magnetoresistance devices. The e-beam deposited structures were processed by KrF excimer laser at the fluences F=0.1–0.25 J cm−2 with 1–1000 pulses. The temperatu...

Thin (6-320 nm) indium tin oxide films were deposited by pulsed excimer (XeCl) laser ablation. The lowest electrical resistivity (1.6×10-6 Ω m) was measured for samples deposited on moderately heated (200 °C) glass substrates. Optical transmissivity of the films in the range 400-1200 nm is higher than 80%. Ultra-thin (~6-9 nm) films were deposited...

The influence of excimer laser processing on the thermal stability, especially on the surface roughness evolution of W1−xSix/Si multilayers (MLs), is studied. MLs with the compositions x=0 (W/Si) and x=0.33, 0.5 and 0.66 were evaporated by e-beam evaporation and co-evaporation onto Si substrates. The samples were irradiated by XeCl laser pulses at...

We ablated Si, SIO and ITO targets in low-pressure O2 with XeCl and KrF laser pulses at fluences of 5-8 J/cm2. The films were deposited on Si and glass substrates at temperatures of 20-600 degrees C. The substrates were generally set parallel to the target. To reduce droplet deposition, some films were deposited in off-axis configuration or using t...

SiO2 and ITO (indium tin oxide) were deposited by ablating Si, SiO and ITO targets, respectively, in low- pressure oxygen atmosphere with pulsed XeCl and KrF excimer laser. The SiO2 and ITO films were deposited on Si<100> and glass (BK7) substrates at temperatures of 20-600 degree(s)C. The substrates were generally set parallel to the target. To re...

Tests were performed to examine the dielectric properties of perfluoropolyether fluids (Fomblin Y) and their transparence to ultraviolet radiation. The purpose was to evaluate the advantage of their use in high-power spark-gaps triggered by pulsed N2 lasers (3371 AA). The results show that the perfluoropolyether fluids exhibit many advantages over...

Multicomponent films like ITO (indium tin oxide) and silica (SiO2) can be efficiently deposited by using the reactive pulsed laser deposition (RPLD) technique. We ablated Si, SiO and ITO targets in low-pressure O2 (0.1–5 Pa) with XeCl and KrF laser pulses at fluences of 5–8 J/cm2. The films were deposited on Si〈100〉 substrates at temperatures of 20...

We have deposited TiAlN films by using the reactive laser ablation technique. TiAl targets were ablated in low-pressure N2 (0.1–10 Pa) atmosphere by 2×104 XeCl excimer laser pulses at the repetition rate of 10 Hz. The laser fluence at the target was set at 6 J/cm2, corresponding to a power density of 0.2 GW/cm2. The films were deposited on Si subst...

The authors present the output characteristics of an excimer laser (XeCl and KrCl) with delayed double UV preionisation. He- and Ne-based mixtures were used for the XeCl laser and Ne-based mixtures for the KrCl laser, at pressures up to 7*105 Pa. For both lasers, maximum output energies (1.1 J/pulse at 308 nm and 0.3 J/pulse at 222 nm) were obtaine...

Describes the theory, design and performance of a linear coil used to measure distributed current pulses. The linear-wound coil acts as a delay line. Its response to transient signals is studied for a generic excitation and for various terminating impedances. The probe rise time is less than 1 ns, the attenuation is about 5.3 mV A-1 and it can reco...

The structure of Ag/Co multilayers (MLs) on laser irradiation is studied. Three MLs with different Ag layer thicknesses, denoted according to the nominal values (nm) as Ag2Co1, Ag4Co1, and Ag6Co1, were exposed to XeCl excimer laser pulses of the fluences (0.1–0.25) J cm−2 for (1–200) times. The structure was examined by X-ray diffraction, hard X-ra...

In this work, we report on a structural and compositional characterization of B–C–N thin films deposited by laser reactive ablation of a B4C target, in low-pressure (5 Pa) nitrogen atmosphere. For target ablation, a KrF excimer laser (λ=248 nm, τ=20 ns) has been used, at the fluences of 6 and 12 J/cm2. Films have been deposited on silicon 〈100〉 sub...

Carbon nitride films were deposited on Si substrates at room temperature by XeCl laser ablation of graphite targets in low pressure N2 atmosphere at the fluence of 12 J/cm2. The films have been submitted to x-ray diffraction and transmission electron microscopy investigations in order to study the structure of the films. Results showed that the sam...

Carbon nanoparticles, prepared by means of ns-laser ablation of carbon can be used for physical modeling of the interstellar dust. Different model for formation of interstellar dust were suggested for the last years, one assumes that carbon grains are generated by condensation in the expanding carbon-rich stellar plasma/vapor of cool red giants. Si...

A hexagonal-BN target was ablated by high-fluence (6 and 12 J/cm2) KrF excimer laser pulses in low-pressure (5 Pa) N2 atmosphere, without any aid of ion bombardment and heating of the Si substrate. Investigations of the deposited films show that the cubic-BN phase was deposited. The film deposited at 6 J/cm2 appears to contain a higher cubic phase...

We report the characteristics of CNx films deposited by excimer laser ablation of graphite targets in low pressure N2 atmosphere. We used a XeCl laser (λ=308 nm, τFWHM=30 ns) at the fluence of 32 J/cm2 (∼1 GW/cm2) and repetition rate of 10 Hz. Substrates were Si 〈111〉 single crystals at room temperature. Different diagnostic techniques [scanning el...

We report on parametric studies of CNx films deposited by excimer laser ablation of graphite targets in molecular nitrogen atmosphere as a function of gas pressure and laser fluence values. Substrates were Si single crystals at room temperature. Deposition rates decrease with increasing nitrogen pressure. The N/C atomic ratio generally increases wi...

Carbon nitride films were deposited on Si substrates at room temperature by XeCl laser ablation of graphite targets in low pressure N2 atmosphere at the fluence of 12 J/cm2. The films have been submitted to x-ray diffraction and transmission electron microscopy investigations in order to study the structure of the films. Results showed that the sam...

Pulsed laser deposition method (PLD) is widely used nowadays to produce smooth, homogeneous thin films on solid surfaces for microelectronic's purpose. Different metal-nitride films as well as nitrides of W, V, Ta, Ni, Co, Pb have been produced in NH3 and N2 atmosphere of a few on Si surfaces with orientation. In the reaction chamber the pulses of...

Pb100−xCox, x=0, 9, 25, 32 and 36 at.% films composed of mutually immiscible metals were codeposited by two electron beam sources in UHV system at the SiO2/Si substrate temperature of 40°C. The samples were processed by XeCl excimer laser irradiation at the fluences F≤0.2 J/cm2 and number of pulses n=1, 10, 100 and 1000. The samples were analyzed b...

Summary form only. The prediction of a covalently bound carbon nitride solid β-C3N4 with characteristics (hardness, bulk modulus) comparable to or even better than those of diamond, stimulated many attempts to synthesise and deposit thin films of this material. Pulsed laser ablation is among the most promising technique to achieve this result

We performed electron microscopy studies of targets subjected to the multipulse laser irradiation in the regime characteristic of reactive pulsed laser deposition from bulk Si in low-pressure ammonia. Experimental evidence is provided concerning the expulsion of liquid droplets from the crater that forms on the target surface. In our opinion, the m...

We have designed and built an ultra-high vacuum chamber which allows thin film deposition on large area (up to 100 mm diameter) flat substrates and on three-dimensional substrates (e.g. 100 mm long, 50 mm diameter cylinders) by the pulsed laser deposition and reactive pulsed laser deposition techniques. Heating of substrates during and after film d...

The influence of substrate temperature on the composition and crystallinity of boron carbonitride (BCN) thin films deposited on (100) Si substrates by sequential pulsed laser deposition (PLD) has been investigated. A correlation between the target composition, the nitrogen pressure involved in the process, and the amount of B, C, and N elements (at...

Carbon nitride films, deposited on Si(111) substrates at room temperature by XeCl laser ablation of graphite targets in low pressure (1, 5, 10, and 50 Pa) N2 atmosphere at the fluence of 12 J/cm2 (~0.4 GW/cm2), have been submitted to accurate x-ray diffraction and transmission electron microscopy investigations in order to study the structure of th...

Optical absorption measurements on CNx thin films produced by reactive pulsed laser ablation (RPLA) at different pressures of nitrogen in the growth chamber were performed. The influence of growth regime on optical properties (n,k) of the CNx films has been examined with IR and UV-VIS spectroscopy. The dependence of the absorption coefficient α on...

Carbon nitride films, deposited on 〈111〉 Si substrates at room temperature by XeCl laser ablation of graphite targets in low pressure (1, 5, 10 and 50 Pa) N2 atmosphere at the fluence of 16 J/cm2 (∼0.5 GW/cm2) have been submitted to accurate X-ray photoelectron spectroscopy (XPS) investigations in order to study the CN chemical bonding in the film...

The Ag/Co multilayers (MLs) showing the giant magnetoresistance (GMR) were thermally processed by excimer laser irradiation at the fluence up to 0.25Jcm−2 with 1–200 pulses. An increase of the GMR ratio from 7.5–15% at 4.2K was observed for MLs with Ag layers composed of randomly oriented Ag grains at lower laser fluences when MLs were not melted....