enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Electron-beam physical vapor deposition - Wikipedia

    en.wikipedia.org/wiki/Electron-beam_physical...

    Another potential problem is that filament degradation in the electron gun results in a non-uniform evaporation rate. However, when vapor deposition is performed at pressures of roughly 10 −4 Torr (1.3 × 10 −4 hPa) or higher, significant scattering of the vapor cloud takes place such that surfaces not in sight of the source can be coated ...

  3. Physical vapor deposition - Wikipedia

    en.wikipedia.org/wiki/Physical_vapor_deposition

    Physical vapor deposition (PVD), sometimes called physical vapor transport (PVT), describes a variety of vacuum deposition methods which can be used to produce thin films and coatings on substrates including metals, ceramics, glass, and polymers. PVD is characterized by a process in which the material transitions from a condensed phase to a ...

  4. List of unsolved problems in chemistry - Wikipedia

    en.wikipedia.org/wiki/List_of_unsolved_problems...

    RNA folding problem: Is it possible to accurately predict the secondary, tertiary and quaternary structure of a polyribonucleic acid sequence based on its sequence and environment? Protein design : Is it possible to design highly active enzymes de novo for any desired reaction?

  5. Electron-beam technology - Wikipedia

    en.wikipedia.org/wiki/Electron-beam_technology

    Electron-beam machining is a process in which high-velocity electrons are concentrated into a narrow beam with a very high planar power density. The beam cross-section is then focused and directed toward the work piece, creating heat and vaporizing the material. Electron-beam machining can be used to accurately cut or bore a wide variety of metals.

  6. Chemical vapor deposition - Wikipedia

    en.wikipedia.org/wiki/Chemical_vapor_deposition

    Chemical vapor deposition (CVD) is a vacuum deposition method used to produce high-quality, and high-performance, solid materials. The process is often used in the semiconductor industry to produce thin films .

  7. List of metal-organic chemical vapour deposition precursors

    en.wikipedia.org/wiki/List_of_metal-organic...

    In chemistry, a precursor is a compound that contributes in a chemical reaction and produces another compound, or a chemical substance that gives rise to another more significant chemical product. Since several years metal-organic compounds are widely used as molecular precursors for the chemical vapor deposition process (MOCVD).

  8. Low-energy plasma-enhanced chemical vapor deposition

    en.wikipedia.org/wiki/Electromagnetically...

    Plasma (argon-only on the left, argon and silane on the right) inside a prototype LEPECVD reactor at the LNESS laboratory in Como, Italy.. Low-energy plasma-enhanced chemical vapor deposition (LEPECVD) is a plasma-enhanced chemical vapor deposition technique used for the epitaxial deposition of thin semiconductor (silicon, germanium and SiGe alloys) films.

  9. Deposition (chemistry) - Wikipedia

    en.wikipedia.org/wiki/Deposition_(chemistry)

    In chemistry, deposition occurs when molecules settle out of a solution. Deposition can be defined as the process of direct transition of a substance from its gaseous form, on cooling, into a solid state without passing through the intermediate liquid state. [1] Deposition can be viewed as a reverse process to dissolution or particle re ...