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Materials for use in vacuum are materials that show very low rates of outgassing in vacuum and, where applicable, are tolerant to bake-out temperatures. The requirements grow increasingly stringent with the desired degree of vacuum to be achieved in the vacuum chamber. The materials can produce gas by several mechanisms.
Ultra-high vacuum (often spelled ultrahigh in American English, UHV) is the vacuum regime characterised by pressures lower than about 1 × 10 −6 pascals (1.0 × 10 −8 mbar; 7.5 × 10 −9 Torr). UHV conditions are created by pumping the gas out of a UHV chamber.
Evaporative deposition: the material to be deposited is heated to a high vapor pressure by electrical resistance heating in "high" vacuum. [4] [5] Close-space sublimation, the material, and substrate are placed close to one another and radiatively heated. Pulsed laser deposition: a high-power laser ablates material from the target into a vapor.
Aluminising vacuum chamber at Mont Mégantic Observatory used for re-coating telescope mirrors. [1] Vacuum deposition is a group of processes used to deposit layers of material atom-by-atom or molecule-by-molecule on a solid surface. These processes operate at pressures well below atmospheric pressure (i.e., vacuum). The deposited layers can ...
In systems where the substrate needs to be cooled, the ultra-high vacuum environment within the growth chamber is maintained by a system of cryopumps and cryopanels, chilled using liquid nitrogen or cold nitrogen gas to a temperature close to 77 kelvins (−196 degree Celsius). Cold surfaces act as a sink for impurities in the vacuum, so vacuum ...
A vacuum chamber is a rigid enclosure from which air and other gases are removed by a vacuum pump. This results in a low- pressure environment within the chamber, commonly referred to as a vacuum . A vacuum environment allows researchers to conduct physical experiments or to test mechanical devices which must operate in outer space (for example ...
Vacuum systems usually consist of gauges, vapor jet and pumps, vapor traps and valves along with other extensional piping. A vessel that is operating under vacuum system may be any of these types such as processing tank, steam simulator, particle accelerator, or any other type of space that has an enclosed chamber to maintain the system in less than atmospheric gas pressure.
During the vacuum process, the circuit board is stationary, assuring no shifting parts. Smooth travel into and out of the vacuum chamber, minimizing vibration, is critical. Employing heat inside the vacuum chamber allows peak temperatures to be achieved during vacuum, assuring shorter time above liquidous and greater process flexibility. High ...