Mass flow meters and mass flow controllers that include mass flow meters are disclosed. A mass flow meter includes a main flow path for a gas, and a bypass with a length, L, within the main flow path. The bypass includes a continuous flow section including a plurality of continuous capillary tubes that each have a length, L. The bypass also includes n flow segments forming n1 spaces within the bypass where n is greater than or equal to 2, and each of the flow segments has a plurality of capillary tubes. The mass flow meter also includes at least one thermal sensor including a sensor tube, and the sensor tube is positioned across at least one of the flow segments to divert a portion of the gas around the at least one of the flow segments and provide a measured flow signal in response to the diverted portion of the gas.

Reliable flow sensors with enclosures that have predictable thermal variations and reduced mechanical tolerances for a more consistent fluid flow and more consistent flow measurements. Thermal variations can be made predictable by using etched structures in silicon blocks. Mechanical tolerances can be reduced using lithography and high-precision semiconductor manufacturing equipment and techniques.

A method of electronically deriving a conclusion of a condition of slurry flow in a non-vertical conduit having a conduit wall and which contains a slurry to flow or flowing along the conduit is provided.

Disclosed is an apparatus for determining a flow of a medium through a pipe, as well as a method for operating the apparatus. The apparatus comprises a heating element at least partially in thermal contact with the medium and which is heatable by means of a heating signal, and a first temperature sensor for registering a temperature of at least one component of the apparatus or the temperature of the medium. The heating element and the first temperature sensor are arranged outside of the pipe. The apparatus includes at least one coupling element, which is at least partially in thermal contact with the heating element, the first temperature sensor and/or a portion of the pipe or tube and serves to assure a thermal coupling between the heating element and the first temperature sensor and between the heating element and the medium.

The micromachined liquid flow sensor devices are enclosed with silicon nitride film as passivation layer to protect device from penetration of liquid into device and avoid the damages of erosion or short circuit etc. One thin layer of silicon dioxide is deposited underneath the silicon nitride layer to enhance the adhesion and reliability of the passivation layer for various applications. The incorporation of silicon dioxide film had successfully provided reliable passivation protection especially for microfluidic devices application. In order to avoid flow turbulence caused by wire bonding wires, the wire bonding wires are omitted by deploying through-substrate conductive vias whereas connected to the carrier printed circuit board of sensor chip. The present invention disclosed a novel micromachining process and designed structure to form hermit sealing between the sensor chip and the carrier printed circuit board. The hermit sealing underneath the sensor chip can protect the bonding connections from exposing to liquid flow media and avoid short circuitry or induce undesired chemical corrosion. More particularly, the embodiments of the current invention relates to formation steps of a micromachined liquid flow sensor including passivation and protection of bonding connection to its carrier printed circuit board, which is therefore capable to offer superb accuracy and reliability for liquid flow measurement.

The microflow sensor includes a base wafer having opposed upper and lower surfaces, and a cap wafer, also having opposed upper and lower surfaces. The base wafer and the cap wafer may be formed from a semiconductor material. A flow sensing element is embedded in the upper surface of the base wafer. The flow sensing element may be any suitable type of flow sensing element, such as a central heater and at least one temperature-sensitive element. A flow channel is formed in the lower surface of the cap wafer and extends continuously between first and second longitudinally opposed edges of the cap wafer. The lower surface of the cap wafer is bonded to the upper surface of the base wafer such that fluid flowing through the flow channel passes above and across the sensing element.

An electric measurement method and apparatus for detecting a mass by an electric capacity (permittivity) or a material's dielectric constant, or alternatively, electric inductance (permeability). The mass may be any phase or combination of phases. The mass may be stationary or flowing. It may comprise discrete particles such as grain, or manufactured products such as ball bearings or threaded fasteners, etc. The mass may be a flow element in a rotameter or similar flow measurement device. The sensor comprises a volume which may be completely full or only partially full of the material. The material may be discrete components or a continuum. Sensor signals may be received by existing planter monitoring systems. In some embodiments the flow sensors are positioned external to the application port. In some embodiments sensors may be utilized which are responsive to the refractive index variation of specific chemicals.

A thermal flowmeter includes a tube, a temperature measuring device disposed on the tube and detecting a first temperature of a fluid, a heating and temperature measuring device disposed on the tube and detecting a second temperature of the fluid, a controller causing the heating and temperature measuring device to generate heat, a power determining unit determining a power consumption of the heating and temperature measuring device, a flow rate obtaining unit converting the power consumption into a flow rate, a flow rate correcting unit correcting the flow rate, a memory unit storing a first zero-point power consumption, a zero-point power ratio calculating unit calculating a zero-point power ratio based on the first zero-point power consumption and a second zero-point power consumption, and a setting unit calculating a correction factor based on the zero-point power ratio and setting the correction factor in the flow rate correcting unit.

Provided is a technique capable of more accurately measuring and outputting a flow rate according to an intended purpose, in a flow rate measurement device. A flow rate measurement device (1) for detecting a flow rate of measurement target fluid flowing through a main flow path (2) includes: a heater (113) configured to heat measurement target fluid; a plurality of temperature detectors (111, 112) that are arranged with the heater interposed in between in a flow direction of the measurement target fluid, and are configured to detect a temperature of the measurement target fluid; and a converter (133) configured to convert a difference in outputs of the plurality of temperature detectors into a heat flow rate or a heat quantity of measurement target fluid flowing through the main flow path.

Disclosed is an apparatus for measuring a fluid flow through a pipe of a semiconductor manufacturing device, in particular a coater or a bonder. The apparatus includes a sealing structure arranged in the pipe, a flow structure having a fluid inlet arranged upstream of the sealing structure and a fluid outlet arranged downstream of the sealing structure, a first chamber arranged in the pipe upstream of the sealing structure, and a second chamber arranged in the pipe downstream of the sealing structure, and a measuring device, wherein the measuring device is adapted to measure a first fluid pressure in the first chamber and a second fluid pressure in the second chamber, wherein the measuring device is configured to determine the fluid flow based on the first and second fluid pressure.