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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 ...
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 ...
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?
Physical vapor deposition takes place in a vacuum and produces a thin film of solar cells by depositing thin layers of metals onto a backing structure. Electron-beam evaporation uses thermionics emission to create a stream of electrons that are accelerated by a high-voltage cathode and anode arrangement.
When the vapor source is a liquid or solid, the process is called physical vapor deposition (PVD), [3] which is used in semiconductor devices, thin-film solar panels, and glass coatings. [4] When the source is a chemical vapor precursor, the process is called chemical vapor deposition (CVD).
Evaporation is a common method of thin-film deposition. The source material is evaporated in a vacuum. The vacuum allows vapor particles to travel directly to the target object (substrate), where they condense back to a solid state. Evaporation is used in microfabrication, and to make macro-scale products such as metallized plastic film.
The size and relative proportion of these pyramidal domains vary with factors that include film thickness, lattice mismatch with the substrate and interfacial chemistry-dependent film nucleation. The synthesis of thin films have the stoichiometry problem due to the high vapor pressures of the elements.
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 .