초록 ▼

An improved system for measuring the flow-rate of a gas by means of ultrasound, including a tubular element in which a plurality of openings are formed to allow one or more gas-flows to flow into the tubular element, and two or more devices for transmitting/receiving ultrasound beams. The system fur

An improved system for measuring the flow-rate of a gas by means of ultrasound, including a tubular element in which a plurality of openings are formed to allow one or more gas-flows to flow into the tubular element, and two or more devices for transmitting/receiving ultrasound beams. The system further includes two or more devices for focusing ultrasound beams. The transmitting/receiving devices transmit and receive, respectively, the ultrasound beams which pass through the focusing devices and the one or more gas-flows inside the tubular element and thus measure the flow-rate thereof.

대표청구항 ▼

An improved system for measuring the flow-rate of a gas by means of ultrasound, including a tubular element in which a plurality of openings are formed to allow one or more gas-flows to flow into the tubular element, and two or more devices for transmitting/receiving ultrasound beams. The system fur

An improved system for measuring the flow-rate of a gas by means of ultrasound, including a tubular element in which a plurality of openings are formed to allow one or more gas-flows to flow into the tubular element, and two or more devices for transmitting/receiving ultrasound beams. The system further includes two or more devices for focusing ultrasound beams. The transmitting/receiving devices transmit and receive, respectively, the ultrasound beams which pass through the focusing devices and the one or more gas-flows inside the tubular element and thus measure the flow-rate thereof. n said base includes an opening extending through said first surface and a passageway in fluid communication said opening, said passageway countable to a source of pressurized fluid, said opening being positioned so as to be alignable with the aperture when the substrate is positioned in a first relationship to said first surface. 3. A chuck according to claim 1, wherein said media comprises a viscous grease. 4. A chuck according to claim 3, wherein said grease has a viscosity at room temperature ranging from 10 to 1,000 mPa-s (milliPascal-second). 5. A chuck according to claim 1, wherein said media comprises a piece of flexible material. 6. A chuck according to claim 5, wherein said flexible material has a Shore durometer ranging from 25 to 95. 7. A chuck according to claim 5, wherein said flexible material has a Shore durometer ranging from 40 to 60. 8. A chuck according to claim 1, wherein said media comprises a piece of flexible material and a viscous grease provided on said flexible material so as to contact the substrate. 9. A chuck according to claim 2, wherein said base comprises a plurality of openings extending through said first surface and a plurality of passageways each fluidly coupled with a corresponding respective one of said plurality of openings. 10. A chuck according to claim 1, wherein said base is made from a ferromagnetic material and said chuck further includes a magnet for urging the substrate toward said base when the substrate is positioned between said magnet and said base so as to contact said magnet. 11. A chuck according to claim 2, wherein said base includes a plurality of vacuum ports. 12. A system for bulge testing a film using pressurized fluid provided by a source, the system comprising: a) a substrate having an aperture with a film covering the aperture; b) a base having a first surface; and c) a viscous media on said first surface for contacting said substrate and creating stiction with said substrate, said media remaining viscous at room temperature for extended periods of time, said media capable of being easily removed from said substrate upon completion of the bulge testing. 13. A chuck according to claim 12, wherein said viscous media has a viscosity such that as a result of said stiction alone a force of at least 1 kPascals is required to separate a 2.54 cm by 2.54 cm square portion of a silicon wafer from said media, the portion having four corners, as measured at one of the corners in connection with peeling the corner away from the substrate. 14. A chuck according to claim 10, wherein said viscous media has a viscosity ranging from 10 to 1,000 mPa-s (milliPascal-second). 15. A chuck according to claim 10, wherein said base includes an opening in said first surface and a passageway in fluid communication said opening, said passageway countable to a source of pressurized fluid, said opening being positioned so as to be aligned with the aperture when the substrate is positioned in a first relationship to said first surface. 16. A bulge testing system for testing a portion of a film of material positioned on a substrate having an aperture positioned adjacent the film, the system comprising: a) a source of pressurized fluid; b) a device for determining deflection of the film portion being bulge tested and providing a first output signal containing information representative of the extent of deflection of the film portion; c) a base having a first surface; and d) a media on said first surface for contacting the substrate, said media inducing stiction with the substrate such that a force of at least 1 KPascals is required to separate a 2.54 cm square portion of a silicon wafer from the media, the portion having four corners, as measured at one of the corners in connection with peeling the corner away from the substrate, said media capable of being easily removed from said substrate upon completion of the bulge testing. 17. A bulge test system according to claim 16, further