Forming gas

About: Forming gas is a research topic. Over the lifetime, 1617 publications have been published within this topic receiving 21995 citations. The topic is also known as: dissociated ammonia atmosphere.

Method and equipment for growing thin films

Abstract: The invention relates to a method and equipment for growing a thin film onto a substrate, in which method a substrate placed in a reaction space (1) is subjected to alternately repeated surface reactions of at least two vapor-phase reactants for the purpose of forming a thin film. The reactants are fed in the form of vapor-phase pulses repeatedly and alternately, each reactant separately from its own source, into said reaction space (1), and said vapor-phase reactants are brought to react with the surface of the substrate for the purpose of forming a solid-state thin film compound on said substrate. The gaseous reaction products and possible excess reactants are removed in gas phase from the reaction space. According to the invention, the gas flow in the reaction space is restricted on the gas flow path after the substrates, whereby the conductance of the gas flow in the reaction space is arranged to be greater cross-directionally to the gas flow at the substrates than after the substrates. The equipment suited to implement the invention comprises vertically or horizontally stacked planar elements (10) of which at least a number are mutually identical and into which are machined reaction chambers (13) and recesses/openings (7, 4) forming gas inflow and outflow channels.

Diffusion of metals in silicon dioxide

Abstract: The diffusion coefficient and solubilities of several metals (Ag, Cu, Au, Pd, and Ti) have been investigated by bias temperature stress (BTS) of (MOS) structures using the candidate metal as the electrode. Temperatures ranged from 250° to 600°C, and the electric fields ranged from +106 to −106 V/cm in ambients of vacuum (10−6 torr), nitrogen, and forming gas . In dry , the activation energy for silver diffusion is found to be 1.24 eV in the temperature range of 275°–365°C. The diffusion coefficient for silver at 300°C in silicon dioxide is . Copper diffusion has an activation energy of 1.82 eV in the temperature range of 350°–450°C in a forming gas environment and a diffusion coefficient in at 450°C of . A thermodynamic model to predict the activation energy of the solid solubility of these metals in and an interstitial diffusion model, that includes both strain and electrostatic energies, which predicts the diffusion activation energy, have been developed. Diffusion coefficients are estimated from a closed form solution of the diffusion equation and the observed behavior of the metal in .

Al-doped ZnO thin films by sol–gel method

Abstract: Transparent and conductive high preferential c-axis oriented ZnO thin films doped with Al have been prepared by sol–gel method using zinc acetate and aluminium chloride as cations source, 2-methoxiethanol as solvent and monoethanolamine as sol stabilizer. Film deposition was performed by dip-coating technique at a withdrawal rate of 1.5 cm min−1 on Corning 1737 glass substrate. The effect of dopant concentration, heating treatment and annealing in reducing atmosphere on the microstructure as well as on the electrical and optical properties of the thin films is discussed. The optical transmittance spectra of the films showed a very good transmittance, between 85 and 95%, within the visible wavelength region. The minimum resistivity of 1.3×10−3 Ω cm was obtained for the film doped with 2 wt.% Al, preheated at 400 °C and post-heated at 600 °C, after annealing under a reduced atmosphere of forming gas.

Low temperature, high quality silicon dioxide thin films deposited using tetramethylsilane (TMS) for stress control and coverage applications

Abstract: Silicon dioxide thin film have been deposited at temperatures from 25° C. to 250° C. by plasma enhanced chemical vapor deposition (PECVD) using tetramethylsilane (TMS) as the silicon containing precursor. At these temperatures, the PETMS oxide films have been found to exhibit adjustable stress and adjustable conformality. Post deposition annealing in forming gas at or below the deposition temperatures has been shown to be very effective in improving the PETMS oxide properties while preserving the low temperature aspect of the PETMS oxides.

Effect of reducing atmosphere on the magnetism of Zn1?xCoxO (0?x?0.10) nanoparticles

Abstract: We report the crystal structure and magnetic properties of Zn1−xCoxO (0≤x≤010) nanoparticles synthesized by heating metal acetates in organic solvent The nanoparticles were crystallized in the wurtzite ZnO structure after annealing in air and in a forming gas (Ar95% + H5%) The x-ray diffraction and x-ray photoemission spectroscopy (XPS) data for different Co content show clear evidence for the Co2+ ions in tetrahedral symmetry, indicating the substitution of Co2+ in the ZnO lattice However, samples with x = 008 and higher cobalt content also indicate the presence of Co metal clusters Only those samples annealed in the reducing atmosphere of the forming gas, that showed the presence of oxygen vacancies, exhibited ferromagnetism at room temperature The air annealed samples remained non-magnetic down to 77 K The essential ingredient in achieving room temperature ferromagnetism in these Zn1−xCoxO nanoparticles was found to be the presence of additional carriers generated by the presence of the oxygen vacancies