NATIONAL VACUUM CONFERENCE IRAN | Year:2008 | دوره:3 |Papers Count:30

RESISTIVITY MEASUREMENTS OF SILICON WAFERS (111) N AND P TYPE WERE PERFORMED BY USING THE VAN DER PAUW TECHNIQUE. THEN THIN FILM OF SILICON WAS DEPOSITED ON SILICON WAFER BY ELECTRON BEAM EVAPORATION. CURVES OF SILICON WAFER IN COMPARISON WITH DEPOSITED SILICON SHOWS THAT FOR CURRENTS LESS THAN 1MA THERE IS A CLEAR DIFFERENT BETWEEN THESE CURVES WHICH IS DUE TO SILICON THIN FILM.

ACCORDING TO IMPORTANCE OF ISOTOPIC ANALYSIS IN NUCLEAR SCIENCES AND TECHNOLOGY, MASS SPECTROMETER HAS A SIGNIFICANT ROLE IN THIS FIELD AS A SENSITIVE AND PRECISE INSTRUMENT. APPLICATION OF VACUUM WAS EXPLAINED BY MEASUREMENT OF BORON ISOTOPIC RATIO. THE MOST EFFECTIVE PARAMETERS ON MEASUREMENTS WERE INVESTIGATED AND OPTIMIZED. OUR MEASUREMENTS SHOWED BY CHOOSING RIGHT PARAMETERS, IT WOULD BE POSSIBLE TO MEASURE B ISOTOPES RATIO WITH RESOLVING POWER OF 400 AND PRECISION OF 0.2% WITH THIS MASS SPECTROMETER.

ON THE ATOMIC SCALE, MOLECULAR DYNAMIC (MD) SIMULATIONS OF THE IMPACT OF A SINGLE CLUSTER ONTO THE SURFACE HAVE BEEN CARRIED OUT. THE IMPACT OF A NI NAN CLUSTER ON A NI (100) SUBSTRATE WAS STUDIED FOR IMPACT ENERGIES OF 1-20 EV/ATOM. WE INVESTIGATED THE CLUSTER SIZE DEPENDENCE OF THE MAXIMUM SUBSTRATE TEMPERATURE TMAX AND OF THE TIME TMAX WITHIN WHICH THIS TEMPERATURE IS REACHED. TIME, CLUSTER SIZE AND CLUSTER ENERGY DEPENDENCE OF THE NUMBER OF DISORDERED ATOMS IN THE SUBSTRATE WAS OBSERVED. WE ALSO INVESTIGATED THE ENERGY AND CLUSTER SIZE DEPENDENCE OF THE NUMBER OF THE SUBSTRATE SPUTTERING AND IMPLANTATION ATOMS.

IN THIS PAPER, AT FIRST DEPOSITION OF AZO THIN FILMS BY VACUUM REACTIVE THERMAL EVAPORATION IS DESCRIBED. THEN, ITS OPTICAL PROPERTIES SUCH AS TRANSPARENCY AND OPTICAL GAP WERE STUDIED. FILM THICKNESSES WERE 100 NM, AND IN THE PRESENT WORK, GLASS SUBSTRATES WERE SELECTED. AND DURING THE DEPOSITION, TEMPERATURE OF SUBSTRATES WAS 150OC. SAMPLES WERE ANNEALED FOR ONE HOUR AT TWO TEMPERATURES 450 AND 550OC. OPTICAL CHARACTERIZATION OF THESE SAMPLES WERE DONE BY UV-VISIBLE SPECTROPHOTOMETER.

THE AIM OF THIS PAPER IS PRESENTING PHYSICAL METHOD OF FABRICATION TI NANOPARTICLE ON GLASS SUBSTRATE. THE PHYSICAL METHOD HAS BEEN USED CALLED GLANCING ANGLE DEPOSITION (GLAD) THAT FOR FIRST TIME SUBMITTED BY A CANADIAN RESEARCH GROUP [1]. FOR PRECISE AND CONTROLLABLE EVAPORATION, ELECTRON BEAM HEATING METHOD HAS BEEN USED. SEM MICROGRAPHS FROM TOP AND CROSS-SECTION VIEWS OF SAMPLES CONFIRMED THE FABRICATION OF TI NANOPARTICLES.

FE78SI9B13 THIN FILMS WERE PREPARED BY PULSED LASER DEPOSITION OF FE-BASED AMORPHOUS RIBBONS. TARGETS WERE ABLATED IN VACUUM BY ND:YAG LASER PULSES. FROM X-RAY DIFFRACTION SPECTRA IT IS FOLLOWED THAT THE FILMS ARE AMORPHOUS AND BY THE AID OF RUTHERFORD BACK SCATTERING ANALYSIS, THE FILM’S COMPOSITION WERE INVESTIGATED. OUR RESULTS SHOWED THAT THE COMPOSITION OF FILMS WERE THE SAME AS TARGET COMPOSITION. THE MAGNETO OPTICAL KERR EFFECT AND THE PRESENCE OF DROPLETS IN THESE THIN FILMS WERE INVESTIGATED. ALSO THE HALL EFFECT IS MEASURED.

AS WE KNOW METALS HAVE EXTREMELY LARGE THIRD ORDER OPTICAL NONLINEARITY AND FAST RESPONSE TIME AND GOOD CANDIDATE FOR ALL OPTICAL DATA PROCESSING. BUT BEING NO TRANSMITTING FOR OPTICAL RADIATION. . IN THIS PAPER WE PROPOSE A NEW KIND OF ARTIFICIAL MATERIALS COMPOSED OF ONE DIMENSIONAL METAL-DIELECTRIC PHOTONIC CRYSTAL AS GLASS\(CU-MGF2)3\AIR WHICH THE THICKNESSES OF TOTAL METAL (CU) LAYERS ARE MORE THAN THREE TIMES OF ITS SKIN DEPTH. ACCORDING TO THE NUMERICAL RESULTS, IT CAN BE SEEN THAT THE TRANSMISSION OF THE ONE DIMENSIONAL PHOTONIC CRYSTAL INCREASED 50% WITH RESPECT TO THE METAL LAYER WITH THE SAME THICKNESS. THE EXPERIMENTAL RESULTS HAVE A GOOD AGREEMENT WITH THEORY.

IN THIS WORK THE VARIOUS TYPES OF OPTICAL SUBSTRATE MATERIAL AND COATINGS THAT USED PRINCIPALLY IN EXCIMER AND UV LASER HAS BEEN STUDIED. THREE SAMPLE ARE MADE WITH, A) MGF2 ON THE BK7, B) MGF2+LIF3 ON THE FUSED SILICA C) AL ON THE BK7. FROM COMPARE OF TRANSMITTION AND REFLECTION SPECTRUMS FROM ABOVE SAMPLES, WE UNDERSTAND THAT IN THE REGION 248-400 NM, AL MIRROR HAS MAXIMUM OF REFLECTION. AND IF AL MIRROR WAS PROTECTED WITH MGF2, USE IN MANUFACTURING OF EXTERNAL RESONATORS IN UV LASERS.

NANOPARTICLE COPPER/CARBON COMPOSITE FILMS WERE PREPARED BY CO-DEPOSITION OF RF-SPUTTERING AND RF-PECVD METHOD FROM ACETYLENE GAS AND COPPER TARGET. WE INVESTIGATE DEPOSITION PROCESS IN THE REGION WHERE BY CHANGING PRESSURE, THE PROCESS CONVERTS TO PHYSICAL SPUTTERING MODE IN CONSTANT POWER REGIME AND AT A CRITICAL PRESSURE BETWEEN 1.5 TO 3 PA. THE ESTIMATED VALUE OF MEAN ION ENERGY AT THIS CRITICAL POINT OF PRESSURE IS CLOSE TO THRESHOLD ENERGY OF PHYSICAL SPUTTERING OF COPPER ATOMS BY ACETYLENE IONS. BY UTILIZING THIS PROPERTY AND BY SETTING INITIAL PRESSURE FROM 1.3 TO 6.6 PA, NANOPARTICLES COPPER/CARBON COMPOSITE FILMS WERE GROWN WITH DIFFERENT COPPER CONTENT. THE COPPER CONTENT OF OUR FILMS WAS OBTAINED BY RUTHERFORD BACK SCATTERING (RBS) AND X-RAY PHOTOELECTRON SPECTROSCOPY (XPS). ATOMIC FORCE MICROSCOPY (AFM) IMAGE AND X-RAY DIFFRACTION (XRD) INDICATED THAT COPPER NANOPARTICLES WERE FORMED IN OUR FILMS.

IN THIS STUDY WC-NI COATING WAS THERMALLY SPRAYED BY HIGH VELOCITY OXY-FUEL (HVOF) METHOD AND THEN HEAT TREATED UNDER VACUUM ATMOSPHERE. PHASE TRANSFORMATION DURING HEAT TREATMENT AT VARIOUS TEMPERATE AND HOLDING TIMES WAS STUDIED BY AN X-RAY DIFFRACTION (XRD) FACILITY EQUIPPED WITH A VACUUM HEATING CHAMBER AND A HIGH TEMPERATURE GONIOMETRY (HTK). COMPARISON OF THE X RAY DIFFRACTION PATTERNS OF FEED STOCK POWDER AND AS SPRAYED COATING INDICATED FORMATION OF AN AMORPHOUS PHASE AND ALSO NI2W4C COMPLEX PHASE IN THE AS SPRAYED COATING. THE UNSTABLE AMORPHOUS PHASE CAN BE CRYSTALLIZED AND STABILIZED BY HEAT TREATMENT AND TRANSFORM TO NIW. THIS PHASE TRANSFORMATION IS SIMILAR TO ALL DIFFUSION CONTROLLED TRANSFORMATIONS AND IS CONTROLLED BY TEMPERATURE AND HOLDING TIME IN HEAT TREATMENT AND THE TEMPERATURE IS MORE EFFECTIVE THAN HOLDING TIME. THE RESULTS ALSO SHOWED THAT HEAT TREATMENT AT 950OC IS NOT SUITABLE FOR THIS PHASE TRANSFORMATION AND 1100OC IS NEEDED FOR THE AFOREMENTIONED TRANSFORMATION.

IN THIS PAPER WE REPORT A MEASUREMENT TECHNIQUE FOR SIMULTANEOUSLY DETERMINING COMPLEX DIELECTRIC CONSTANT AND THICKNESS OF ULTRA-THIN FILMS. FOR THIS PURPOSE WE ANALYZE A SET OF REFLECTED AND TRANSMITTED LIGHT INTENSITY EQUATIONS AND OBTAIN REAL AND IMAGINARY PARTS OF THE DIELECTRIC CONSTANT AND THICKNESS OF THE GROWING FILM. EXPERIMENTAL RESULTS OBTAINED BY A DESIGNED REAL-TIME SYSTEM IS REPORTED FOR ALUMINUM COATING ON GLASS SUBSTRATE AT TWO LASER LIGHT WAVELENGTHS OF 650NM (LIGHT RED) AND 780NM (NEAR INFRARED).

IN THIS PAPER DESIGN AND CONSTRUCTION OF A SYSTEM IN ORDER TO SYNTHESIZE NANO PARTICLES BY CVC METHOD IN VACUUM SYSTEM IS PRESENTED. MAIN COMPONENTS INCLUDING VACUUM CHAMBER, SPIN LIQUID NITROGEN TANK BUBBLING UNIT, MECHANICAL FEEDTHROUGHS, QUARTZ PIPE ATTACHED TO VACUUM SYSTEM AND SOME OF SPECIFICATIONS OF NANOPARTICLES SYNTHESIZED BY THIS SYSTEM ARE DESCRIBED. TIO2 NANOPARTICLES WERE SYNTHESIZED AND CHARACTERIZED.

THE NIX FE100-X (X=60 AND 80) THIN FILMS WITH THE THICKNESS ABOUT 50-100 NANOMETER WERE FABRICATED BY THERMAL EVAPORATION TECHNIQUE. THE LAYERS WERE STUDIED BY XRD, SEM AND EDAX. USING ELECTRICAL MEASUREMENT, THE SPECIFIC RESISTIVITY AND TCR OF THE SPECIMEN WERE CALCULATED AND WERE COMPARED WITH THE RESULT OF THOSE MADE BY OTHER METHODS.

UP TO NOW, THE DESIGN AND FABRICATION OF ABERRATION- FREE OPTICAL ELEMENTS (BE IT CHROMATIC OR GEOMETRIC) HAS BEEN DONE, MAINLY THROUGH COMBINATION OF OPTICS WHICH INVOLVES CUMBERSOME CALCULATIONS. HOWEVER, SINCE ACTIVE APPEARANCE OF HOLOGRAPHY, THE OLD METHOD IS GRADUALLY BEING REPLACED BY HOLOGRAPHIC FABRICATION METHODS. THESE NEW METHODS HAVE RESULTED IN PRODUCTION OF A NEW GENERATION OF OPTICS CALLED HOLOGRAPHIC OPTICAL ELEMENT (HOE). IN THIS WORK THE METHOD OF SILVER HALIDE SENSITIZED GELATIN (SHSG) IS USED IN ORDER TO MAKE PHASE TRANSMISSION HOLOGRAMS. THE TERM SHSG DENOTES AN ALL–GELATIN PHASE MATERIAL WHICH RECORDS THE INITIAL IMAGE INFORMATION THROUGH PHOTON ABSORPTION BY THE SILVER HALIDE THE IMAGE IS STORED AS THE DIFFERENCES IN THE REFLECTIVE INDEX WITHIN THE REMAINING GELATIN. BY PLACING THE SAMPLE IN THE VACUUM AT THE END OF PROCESSING FOR DEHYDRATION, WE INCREASE THE QUALITY AND KEEP THE STABILITY UP TO THE TEMPERATURE OF 110ºС. THIS TECHNIQUE THAT PROPOSED RECENTLY IS ONE OF THE MOST PROMISING TECHNIQUES FOR THE FABRICATION OF TRANSMISSION HOE. WE MADE PHASE TRANSMISSION GRATINGS WITH DIFFRACTION EFFICIENCY OF 70% WHICH IS COMPARABLE WITH RECENT WORLD RECORDS.

IN THIS WORK, EFFECT OF POROSITY ON CDO/PSI/SI PHOTODIODE WAS STUDIED BY SCANNING TUNNELING SPECTROSCOPY. THE CDO/PSI/SI MULTILAYERS WERE PREPARED BY ELECTROCHEMICAL ANODIZING OF P TYPE SILICON AND PULSE LASER DEPOSITION WAS EMPLOYED FOR CADMIUM OXIDE DEPOSITION. IN ORDER TO COMPENSATE OXYGEN LACK IN CDO LAYERS, SAMPLES WERE ANNEALED AT 500OC IN AIR ATMOSPHERE FOR 10 MIN. THE CADMIUM OXIDE MORPHOLOGY AND PORE’S DIAMETER OF POROUS SILICON LAYER WERE INVESTIGATED BY SEM AND AFM METHODS. THE XRD ANALYSIS AND UV-VIS SPECTROSCOPY WERE USED TO STUDY THE CRYSTALLINE STRUCTURES AND ESTIMATE THE BAND GAP ENERGY OF CDO LAYERS, RESPECTIVELY. THE DIFFERENT POROSITY OF SILICON LAYERS WERE ACHIEVED BY CHANGING CURRENT DENSITY DURING OF ELECTROCHEMICAL ANODIZING AND EFFECT OF POROSITY ON ELECTRO OPTICAL PROPERTIES OF CDO/PSI/SI STRUCTURES WERE STUDIED. THE RESULTS OF CURRENT-VOLTAGE MEASUREMENT IN DARK AND IN THE PRESENT OF LIGHT SHOWS THAT THERE IS A SPECIAL POROSITY THAT OPTIMIZES THE PHOTODIODE PROPERTIES OF THE SAMPLES.

IN THIS PAPER A TI/SI METAL-SEMICONDUCTOR JUNCTION AS THE GATE, WAS FORMED BY PLASMA DEPOSITION ON THE CLEAN SI SURFACE OF P-SI/SIGE/SI INVERTED MODULATION DOPED STRUCTURES. THERE IS A TWO DIMENSIONAL HOLE GAS (2DHG) IN THE ALLOY LAYER OF THIS STRUCTURE AND ITS AREAL SHEET DENSITY NS CAN BE CONTROLLED BY APPLICATION A VOLTAGE TO THE GATE. THE TI/SI INTERFACE CHARGE DENSITY HAS BEEN DETERMINED BY THEORETICAL SIMULATION OF EXPERIMENTAL RESULTS OF NS – VG. THE RESULTS INDICATES THAT AS THE SI CAP THICKNESS INCREASES FROM 180 UP TO 480NM, THE TI/SI INTERFACE CHARGE DENSITY VARIES FROM 4.6 DOWN TO 1.95×1015 CM-2 RESPECTIVELY.

THE PRESENT WORK INTRODUCES A NEW VACUUM INSULATION. IN THIS INSULATION, PRESSURIZED AIR IS USED FOR INFLATING AND STIFFENING THE LOAD-CARRYING STRUCTURE IN ORDER TO PREVENT SCRUNCHING THE ENVELOPE. BY INFLATION OF THIS STRUCTURE, THE VACUUM IS PRODUCED IN LOCATIONS WHICH ARE OUT OF STRUCTURE. IN THIS PAPER THE THERMAL AND STRUCTURAL BEHAVIOR OF THIS INSULATION ARE INVESTIGATED USING ANSYS 10.0. THE OBTAINED RESULTS JUSTIFY THE ACCEPTABILITY OF CHARACTERISTICS OF THIS INSULATION.

CARBON NANOTUBE REINFORCED ALUMINUM MATRIX COMPOSITE WAS FABRICATED BY PRESSING FOLLOWED SINTERING IN VACUUM MEDIA TECHNIQUES. FIRST THE EFFECTS OF SINTERING TEMPERATURE AND TIME ON DENSITY, POROSITY AND HARDNESS AND THEN VARIATION OF PHYSICAL PROPERTIES SUCH AS DENSITY AND HARDNESS WITH PERCENTAGE OF CNT HAVE BEEN INVESTIGATED. THE RESULTS SHOWN THAT INCREASING OF THE SINTERING TEMPERATURE AND TIME AND INCREASING OF THE CNT PERCENTAGE INCREASED THE DENSITY AND HARDNESS OF COMPOSITE AND DECREASED THE POROSITY.

IN THIS INVESTIGATION, THE HYDROPHILIC AND OPTICAL PROPERTIES OF TIXSI1-XO2 COMPOUND THIN FILMS DEPOSITED BY REACTIVE RF CO-SPUTTERING WERE STUDIED. THE EFFECT OF TIO2 CONCENTRATION ON THE HYDROPHILICITY OF TIXSI1-XO2 COMPOUND FILMS WAS INVESTIGATED AND IT WAS SHOWN THAT THE TI0.56SI0.44O2 COMPOUND THIN FILM POSSESSED A SUPER HYDROPHILIC SURFACE FOR A LONG TIME UNDER DARKNESS. THE OPTICAL PROPERTIES OF TIXSI1-XO2 COMPOUND THIN FILMS WERE ALSO STUDIED BY MEASURING THE TRANSMITTANCE AND REFLECTANCE OF THE FILMS USING UV-VISIBLE SPECTROPHOTOMETER. IT WAS FOUND THAT TRANSMITTANCE AND REFLECTANCE OF THE COMPOUND FILMS DECREASED AND INCREASED WITH INCREASING TIO2 CONCENTRATION, RESPECTIVELY.

ION BEAM ANALYSIS IS A POWERFUL TOOL FOR THE ANALYSIS AND CHARACTERIZATION OF MATERIALS. SOME OF THESE METHODS SUCH AS PIXE ARE ROUTINELY USED SINCE 1975 IN TEHRAN VAN DE GRAFF LABORATORY. OTHER METHODS SUCH AS MICRO-PIXE, RBS-CHANNELING AND ERD BECAME OPERATIONAL SINCE 2001. IN THIS LECTURE, AFTER A SHORT DESCRIPTION OF THESE METHODS, SOME APPLICATIONS OF THESE ANALYTICAL METHODS IN DIFFERENT FIELDS OF RESEARCH WILL BE PRESENTED.

GROWS RATE AND FUNCTION OF RAMAN FORWARD INSTABILITY ASSOCIATED TO THE INTERACTION OF PICOSECOND SHORT LASER PULSE (I ≤ 1018W/CM2) WITH A LOW DENSITY COLD PLASMA, IN WEAKLY RELATIVISTIC REGIME, IS INVESTIGATED. IT IS SHOW THAT TWO SCATTERED ELECTROMAGNETIC WAVES CALLED STOKES AND ANTI-STOKES GIVE RISE THIS INSTABILITY, YIELD PONDER MOTIVE FORCE LEAD TO WAKE WAVES AND AS A RESULT TO MODULATION OF PLASMA DENSITY. IN ADDITION, IT IS SHOW THAT RAMAN FORWARD INSTABILITY OCCURS AT FOUR STAGE, GROWS WITH A GIVEN RATE IN PLASMA.

IN THE PRESENT EXPERIMENTAL WORK, TITANIUM THIN FILMS HAVE BEEN PREPARED ON GLASS SUBSTRATES BY MAGNETRON SPUTTERING AND THE EFFECT OF FOUR IMPORTANT PARAMETERS OF SUBSTRATE TEMPERATURE, ARGON GAS PRESSURE, ION ENERGY AND THE BASE PRESSURE ON THE ADHESION OF TI LAYERS TO SUBSTRATES HAVE BEEN INVESTIGATED. EXPERIMENTAL RESULTS SHOW THAT THE ADHESION OF TI FILMS TO THE GLASS SUBSTRATES IS INCREASED BY INCREASING THE SUBSTRATE TEMPERATURE BUT THE ADHESION IS DECREASED BY INCREASING THE WORKING GAS PRESSURE. INCREASING THE ENERGY OF THE INCIDENT IONS CAUSES THE ADHESION TO ENHANCE. MECHANISMS INVOLVED IN VARIATIONS OF ADHESION BY THE PRESSURE, SUBSTRATE TEMPERATURE AND ENERGY OF THE INCIDENT IONS ARE EXPLAINED.

TIN DOPED OXIDE, ITO THIN FILMS WERE PREPARED ON GLASS SUBSTRATE AT 200°C BY ELECTRON BEAM TECHNIQUE. DEPOSITED FILMS WERE ANNEALED AT DIFFERENT TEMPERATURES AND DIFFERENT ENVIRONMENT. THE RESISTANCE OF FILMS DEPOSITED IS ABOUT 1/84×10-1ΩCM AND FALLS DOWN TO 1/35×10-4ΩCM AFTER ANNEALING 500°C AT ATMOSPHERE AND 400OC. AVERAGE TRANSMITTANCE IN VISIBLE RANGE IS ABOUT 78/66%. THE LATTICE CONSTANT OF ITO THIN FILMS WERE 10/08A0 BY XRD. OPTICAL BAND GAP CALCULATED 4/222. THE STRUCTURAL, ELECTRICAL AND OPTICAL CHARACTERISTICS OF ITO SAMPLES HAVE BEEN ANALYZED BY XRD, AFM, FOUR POINT PROBE METHOD AND UV/VIS/IR SPECTROPHOTOMETER.

SIO2 AND SI3N4 LAYERS ARE FORMED ON INSB WAFER BY PLASMA ENHANCED CHEMICAL VAPOR DEPOSITION (PECVD) TECHNIQUE, DUE TO THE SIGNIFICANT OF SURFACE LEAKAGE CURRENT IS LIMITING IN LONG WAVELENGTH INFRARED DETECTORS, WHICH GIVES RISE TO MIS (METAL INSULATOR SEMICONDUCTOR) CAPACITOR FORMATION. IN THIS DOCUMENT, ALL OF DEPOSITION PROCEDURES, SEMICONDUCTOR SURFACE PASSIVATION NECESSITY, QUALITY OF DEPOSITED LAYER AND IDENTIFYING THE TYPE OF SUBSTRATE WILL BE DISCUSSED.

THIN LAYERS OF TIN OXIDE AND ZINC OXIDE WERE DEPOSITED ON SILICA SUBSTRATES BY PHYSICAL VAPOR DEPOSITION IN A VACUUM CHAMBER USING ELECTRON BEAM HEATING. THE CHAMBER PRESSURE WAS~10-5 TORR AND THE SUBSTRATES WERE AT ROOM TEMPERATURE. THE DEPOSITED TIN OXIDE LAYERS WERE ELECTRICALLY INSULATING AND WERE PROVED TO BE AMORPHOUS. THESE LAYERS WERE CRYSTALLIZED IN CONTROLLED ATMOSPHERES AT DIFFERENT TEMPERATURES. THE CRYSTALLIZED LAYERS WERE SNO2. THE KINETICS OF THE CRYSTALLIZATION PROCESS IN DIFFERENT CONDITIONS WAS INVESTIGATED. THE APPLICATION OF A SIMILAR TECHNIQUE TO ZINC OXIDE, ON THE OTHER HAND, PROVED UNSUCCESSFUL AS IT RESULTED BLACK CONDUCTIVE LAYERS WEAKLY ADHERING TO THE SUBSTRATE SURFACE.

ELECTRICAL CHARACTERIZATION OF SILICON-BORON SLAB DOPING IN THE SI/SI-B/SI STRUCTURE GROWN BY MOLECULAR BEAM EPITAXY (MBE) HAS BEEN CONSIDERED IN THIS PAPER. AFTER GROWTH, THE TRANSVERSAL HAL VOLTAGE HAS BEEN MEASURED IN THE 60-300K TEMPERATURE RANGE AND TEMPERATURE DEPENDENCE OF HALL COEFFICIENT HAS BEEN DETERMINED. THE VOLUME CONCENTRATION AND BINDING ENERGY OF DO PANT, HALL FACTOR AND LIFTING COEFFICIENT OF FERMI LEVEL HAVE BEEN DETERMINED BY THEORETICAL SIMULATION OF HOLE SHEET DENSITY VERSUS TEMPERATURE.

THIS PAPER IS AN EXPERIMENTAL STUDY ABOUT DEPOSITION CONDITION OF AU &, CU IN THIN FILM COATING. IN COATED SAMPLES WITH VARIATION AMOUNT AND DENSITY AU &, CU MATERIALS, KIND AND NUMBER OF LAYERS CHANGED. THE ABOVE MENTIONED SAMPLES WERE MADE BY PVD COATING (PHYSICAL VAPORATION DEPOSITION) WITH BALZERS 510 MACHINE, ON THE GLASS SUBSTRATES. METHOD OF VAPORIZATION WAS "THERMAL EVAPORATION", WITH 4*10-6 TORR PRESSER. IN COATING PROCESS WITH 2.5G AU &, 0.5G CU AND Ρ=19.3G/CM3, BY RBS TEST IS FIND, COATED SAMPLE HAS 6 LAYERS AND NEXT LAYER OF GLASS HAS 10% CU AND 90% AU. THEN, THIS SAMPLE IS AN INTERNAL MIRROR.

IN THIS INVESTIGATION EFFECT OF POST-OXIDATION TEMPERATURE ON CORROSION RESISTANCE OF NITRO CARBURIZED AISI 5115 STEEL WAS STUDIED. FOR THIS PURPOSE, QUENCHED AND TEMPERED STEEL WAS PULSE PLASMA NITRO CARBURIZED AT 550ºC, FOR 5H, IN 80%N2+13%H2+7%CO2 GAS MIXTURE AT PRESSURE OF 3 TORR. IMMEDIATELY AFTER NITRO CARBURIZING, SAMPLES WERE POST-OXIDIZED AT 400OC, 450ºC AND 500OC, FOR 1H, BY CHANGING ATMOSPHERE TO 75%O2+25%H2 GAS MIXTURE. THE PROPERTIES OF LAYERS WERE STUDIED BY USING X-RAY DIFFRACTION AND SECONDARY ELECTRON MICROSCOPY. STUDY OF PHASES WHICH ARE FORMED IN OXIDE LAYER, REVEALED THAT OF FORMATION OF FE3O4 PHASE, IS INCREASED BY DECREASING POST-OXIDATION TEMPERATURE. THE RESULT OF POLARIZATION TEST SHOWED THAT CORROSION RESISTANCE IS IMPROVED BY NITRO CARBURIZING AND IT IS FURTHER IMPROVED BY POST-OXIDATION.

IN THIS PAPER THE SIMULATION RESULTS OF AMORPHOUS SILICON DEPOSITION BY PLASMA ENHANCED CHEMICAL VAPOR DEPOSITION METHOD AND THE EFFECTS OF CHAMBER PRESSURE ON CHARACTERISTICS OF THE DEPOSITED LAYER IS PRESENTED. FURTHERMORE, TWO QUALITATIVE CRITERIONS ARE DEFINED FOR EVALUATION OF THE QUALITY AND UNIFORMITY OF DEPOSITED LAYER. THE EFFECT OF CHAMBER PRESSURE ON DEPOSITION RATE, BOTH OVER THE SUBSTRATE AND THE POWER ELECTRODE IS FOUND.

WOX FILMS WERE DEPOSITED BY LASER ABLATION OF WO3 TARGETS AT 250OC TEMPERATURE, 100 MTORR OXYGEN PARTIAL PRESSURE AND 1×10-5 TORR VACUUM. SURFACE CHEMICAL STATES OF DEPOSITS WERE DETERMINED BY X-RAY PHOTOELECTRON SPECTROSCOPY (XPS). RESULTS SHOWED THAT DEPOSITS IN OXYGEN PARTIAL PRESSURE CONTAINS W6+WITH X~3.1, WHILE VACUUM DEPOSITS HAVE DIFFERENT W STATES PERCENTAGE DISTRIBUTION AS W4+> W5+> W6+> W0, AND X~1. WE USED ELECTRICAL RESISTANCE MEASUREMENTS TO STUDY THE SUB-STOICHIOMTRY IN VACUUM DEPOSITION PROCESS. FAST MEASUREMENT OF FILM RESISTANCE IN VACUUM DEPOSITION REVEALED SOME MICROSECOND FLUCTUATIONS MODULATED ON THE TIME VARIATION CURVE OF ELECTRICAL RESISTANCE.