Most people assume a vacuum is created by simply pulling the air out. That is partly correct – but the engineering behind it is more interesting than it sounds, and the method you use depends entirely on how deep a vacuum you need. Creating a rough vacuum is straightforward. A
How Vacuum Systems Pass Power, Fluid, Signals, and Motion Without Breaking the Seal A vacuum chamber is designed to keep the outside world out. But a useful vacuum system still has to do real work inside that sealed environment. That means engineers need a way to pass electricity, signals, light,
How Vacuum Engineering Powers the Technologies That Shape Our World There is a category of engineering that makes nearly everything we consider technologically advanced possible – and receives almost none of the credit for it. It does not have a flashy name. It does not generate breathless headlines. When a
People use the word “vacuum” as if it describes a single condition. It does not. Vacuum exists on a spectrum – a very wide one – and the difference between one end and the other is not a matter of degree. It is a matter of the physics involved, the
Ultra-high vacuum (UHV) refers to a pressure regime at or below approximately 10⁻⁹ torr (~1.3×10⁻⁹ mbar). At these pressures, gas-surface interactions and trace leak paths dominate system behavior more than bulk gas flow does. UHV is used in semiconductor manufacturing, surface science, synchrotron beamlines, electron microscopy, quantum and cryogenic platforms,
ConFlat (CF) flanges use a copper gasket that is cold-welded between two stainless steel knife edges, creating a true metal-to-metal hermetic seal capable of achieving system pressures below 10⁻¹² torr and helium leak rates of 10⁻¹³ torr·L/s or better. KF (Klein Flange, also called NW or ISO-KF) flanges use an
Ceramic-to-metal seals (typically alumina brazed to Kovar or stainless steel) offer superior mechanical strength, higher temperature capability, and better resistance to thermal cycling than glass-to-metal seals. Glass-to-metal seals (borosilicate or matched glasses bonded to Kovar or other alloys) are less expensive, well-characterized electrically, and adequate for moderate-temperature and pressure environments.
Direct Answer Choose CF flanges when your system must reach pressures at or below 10⁻⁷ torr, requires bakeout above 150°C, or must meet a helium leak-rate specification at or below 1×10⁻⁹ atm·cc/sec. Choose KF flanges for rough vacuum, high vacuum up to about 10⁻⁷ torr, and any connection that benefits
Semiconductor process tools – including PVD, ALD, CVD, ion implantation, and advanced etch systems – use UHV or near-UHV conditions to minimize surface contamination and improve film purity. Hermetic feedthroughs carry electrical power, RF signals, thermocouples, and motion actuators through chamber walls without introducing leak paths. Selecting feedthroughs with the