Summary |
Two new kinds of the standard leak elements (SLEs), with a microfluidic channel in diameter of several-micrometerslength of several-hundred-micrometers, have been developed by femtosecond (fs) laser micromachining. A technique based on the conductance modulation method can be used to accurately determine the tiny conductance ( 1×10-6 L s-1) of these SLEs.
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Scientific Breakthrough |
Most leak paths of the SLEs in the literature (e.g., Nano hole, multichannel, AAO) were fabricated in a non-metallic substrate a subsequent sealing process was hence required to attach these non-metallic leak elements to flanges for vacuum applications. Torr Seal® is the most commonly used sealant for vacuum sealing, but its outgassing rate is of order 10-7 mbar L s-1 cm-2a baking temperature must not exceed 120 0C. We propose a simple approach using fs laser micromachining to make the SLEs, which can be compatible with an UHV environmentcan withstand higher baking temperatures.
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Industrial Applicability |
This invention can serve to (a) calibrate the sensitivity of an ionization gaugeresidual gas analyzer (RGA) for various gases, (b) calibrate the leak rate of a helium leak detector, (c) measure the pumping speedthe sorption capacity of a vacuum pump, (d) supply a preciseconstant gas flow in cooperation with a low-vacuum gauge (e.g., capacitance diaphragm gauge, CDG),(e) be a tiny differential pumping element, between which a desired pressure gradient can be attained with an appropriate pumping speed.
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