Papers by Keyword: Laser CVD

Abstract: (004)-oriented γ-LiAlO₂ films were prepared on poly-crystalline AlN substrates by laser chemical vapor deposition at deposition temperature (T_dep) of 1100–1250 K, molar ratio of Li/Al (R_Li/Al) of 1.0–10 and low total pressure (P_tot) of 100–200 Pa. The (004)-oriented γ-LiAlO₂ films consisted of pyramidal grains with a columnar structure. The deposition rate of (004)-oriented γ-LiAlO₂ films reached to 65–72 μm h^-1.

Abstract: Titania (TiO₂) Films Having Dense and Solid Microstructure Were Prepared by Laser Chemical Vapor Deposition Using CO₂ Laser. The Effects of Deposition Temperature (T_dep) and Total Chamber Pressure (P_tot) on Phase and Microstructure of TiO₂ Films Were Investigated. At P_tot = 600 Pa and T_dep = 790 K, Rutile TiO₂ Film Had a Polygonal Platelet Grains 2 μm in Size. At P_tot = 600 Pa and T_dep = 1010 K, Rutile TiO₂ Film Had (110) Orientation and Consisted of a Truncated Polyhedron 5–6 μm in Size. At P_tot = 200 Pa and T_dep = 955 K, Rutile TiO₂ Film Has a Solid Columnar Having Faceted Surface. A Dense and Solid TiO₂ Film Was Obtained at P_tot = 200 Pa and T_dep = 1120 K. The Deposition Rate of TiO₂ Solid Film Was Reached 240 μm h⁻¹.

Abstract: C-Axis-Oriented Y₂Ba₄Cu₇O_15-δ (Y247) Films Were Prepared on Multilayer-Coated Hasterolly Tape Substrate by Laser Chemical Vapor Deposition with Ultrasonically Nebulized Liquid Precursor. At a Low Precursor Concentration of 0.01 mol l⁻¹ and Deposition Temperature of 933 K, Single-Phase Y247 Film with Significant c-Axis Orientation Was Obtained. At a Precursor Concentration of 0.1 mol l⁻¹ and Deposition Temperature 983 K, a-Axis-Oriented YBa₂Cu₃O_7-δ (Y123) Was Codeposited with C-Axis Oriented Y247 Film.

Abstract: Ba²TiO₄ and Ba₄Ti₁₃O₃₀ Thick Films Were Prepared by Laser Chemical Vapor Deposition Using Ba- and Ti-Dipivaloylmethanate Precursors. Single-Phase Ba₂TiO₄ Thick Films Were Obtained at 845–946 K and Ba/Ti Source Molar Ratio 2.4. Single-Phase Ba₄Ti₁₃O₃₀ Films Were Obtained at 944–1011 K and Ba/Ti Source Molar Ratio 0.38. Ba₂TiO₄ Thick Films Consisted of Truncated Grains, while Ba4ti13o30 Thick Films Had Shellfish-Like Grains. Ba₂TiO₄ and Ba₄Ti₁₃O₃₀ Thick Films Showed a Columnar Growth and their Deposition Rates Were 72 and 132 μm h⁻¹, Respectively.

Abstract: B-Axis-Oriented Bati2o5 Nanopillars Were Prepared on (100) Mgo Single Crystal Substrate by Laser Chemical Vapor Deposition Using Ba and Ti Dipivaloylmethanate Precursors. B-Axis-Oriented Bati2o5 Nanopillars Were Approximately 250–400 Nm in Width and 2.5 μm in Height. Deposition Rate of Bati2o5 Nanopillar Arrays Was about 75 μm H−1.

Abstract: Α-Al₂O₃ Films Were Prepared by Laser Chemical Vapor Deposition and the Effects of Precursor Evaporation Temperature (T_vap) and Oxygen Gas Flow Rate (FRo) on Phase and Orientation of Al₂o₃ Films Were Investigated. at T_vap = 413 K, (100)-Oriented α-Al₂O₃ and θ-Al₂O₃ Were Codeposited. the Amount of θ-Al₂O₃ Increased with Increasing FRo. at T_vap = 433–443 K, α-Al₂O₃ Films Showed a (001) Orientation. (100)- and (001)-Oriented α-Al₂O₃ Films Had a Rectangular- and Hexagonal-Shaped Grains, Respectively, and Showed a Columnar in Cross Section. Grain Size of (100)- and (001)-Oriented α-Al₂O₃ Films Decreased from 10 to 2 μm with Increasing FRo from 0.085 to 0.85 Pa m³ s⁻¹. Deposition Rate Increased from 100 to 300 μm h⁻¹ with Increasing T_vap from 413 to 443 K.

Abstract: α-Al2O3 and α-Al2O3/TiN multilayer films were prepared on Ti(C,N)-based cermet substrate by laser chemical vapor deposition.α-Al2O3 and NaCl-type TiN films were prepared at Tdep = 1148 K. α-Al2O3/TiN multilayer film showed dense structure of cross section, and its surface morphology consisted of aggregated spherical grains. The adhesion of α-Al2O3/TiN multilayer film prepared on Ti(C,N)-based cermet was higher as compared with α-Al2O3 film directly prepared on the cermet.

Abstract: Al2O3-AlN composite film was first prepared by laser chemical vapor deposition (laser CVD) using aluminum acetylacetonate (Al(acac)3) and ammonia (NH3) as source materials. The effects of NH3 on the crystal phase, composition and microstructure were investigated. The crystal phase changed from α-Al2O3 to AlN gradually with increasing the mole ratio of NH3 to Ar. Al2O3-AlN composite film was obtained at NH3/Ar ratio ranged from 0.09 to 0.16 (Tdep = 862–887 K), and AlN granular grains were embedded in between α-Al2O3 polyhedral grains.

Abstract: Nearly stoichiometric TiN_x films were deposited on Al₂O₃ substrates by laser enhanced chemical vapor deposition (CVD) with tetrakis (diethylamido) titanium (TDEAT) and ammonia as the source materials. Emphases were given on the effects of laser power (P_L) and pre-heating temperature (T_pre) on the composition and deposition rate of TiN_x films. Single phase of TiN_x films with columnar cross section were obtained. The ratio of N to Ti in TiN_x films increased with increasing P_L and was close to stoichiometric at P_L > 150 W. The deposition rate of TiN_x films with a depositing area of 300 mm² was about 18-90 µm/h, which decreased with increasing P_L and T_pre.