A vaporizer (20) is shaped to define a flow channel (120) that is open to an environment external to the vaporizer at first and second ends of the flow channel. At the first end of the flow channel is a mouthpiece (112) of the vaporizer. A flow sensor (114) includes (a) a nanoscale resistive element (200) disposed at least partially within the flow channel and (b) sensing circuitry (115) configured to measure a change in the nanoscale resistive element due to airflow within the flow channel. Other applications are also described.

A thermal airflow sensor includes a sensor element, a bonding wire, a resin, and a protective film. The sensor element has a thin-wall portion. The thin-wall portion has a heating resistor. The bonding wire is electrically connected to the sensor element. The resin covers the bonding wire. The protective film is formed on a surface of the sensor element so that the heating resistor is exposed. The protective film has at least a slit between the resin and the thin-wall portion.

A thermal airflow sensor includes a sensor element, a bonding wire, a resin, and a protective film. The sensor element has a thin-wall portion. The thin-wall portion has a heating resistor. The bonding wire is electrically connected to the sensor element. The resin covers the bonding wire. The protective film is formed on a surface of the sensor element so that the heating resistor is exposed. The protective film has at least a slit between the resin and the thin-wall portion.

A flow sensor chip capable of preventing power from being wasted during the electrification of a heater is provided. The flow sensor chip includes a first lead portion connected to an end of a heater portion, a second lead portion connected to the other end of the heater portion, a first electrode pad connected, directly or through a connection portion formed of a material having an electrical conductivity equal to or greater than the heater conductivity, to an end of the first lead portion on a side which is not connected to the heater portion, and a second electrode pad connected, directly or through a connection portion formed of a material having an electrical conductivity equal to or greater than the heater conductivity, to an end of the second lead portion on a side which is not connected to the heater portion.

A fluid sensing apparatus includes a fluid sensor configured to detect a temperature distribution on a detection surface caused by heating, and output a signal value corresponding to a flow of a fluid; a falling time counting unit configured to count a falling time of the signal value after stopping the heating; and a failure determining unit configured to perform failure determination based on the falling time.

A physical quantity measurement device includes a physical quantity detector and a support plate part superposed on a back surface of the physical quantity detector to support the physical quantity detector. The physical quantity detector includes a recessed part on the back surface, and a membrane part defining a bottom surface of the recessed part and being provided with a detection element for detecting a physical quantity of a fluid in a measurement low path. An area of the support plate part covering the recessed part includes a communication hole communicating with the recessed part. A peripheral edge portion of a hole opening, which is an end of the communication hole adjacent to the recessed part, is spaced apart, toward the inside, from a peripheral edge portion of a recess opening, which is an end of the recessed part adjacent to the support plate part.

A physical quantity measurement device includes a physical quantity detector and a support plate part superposed on a back surface of the physical quantity detector to support the physical quantity detector. The physical quantity detector includes a recessed part on the back surface, and a membrane part defining a bottom surface of the recessed part and being provided with a detection element for detecting a physical quantity of a fluid in a measurement low path. An area of the support plate part covering the recessed part includes a communication hole communicating with the recessed part. A peripheral edge portion of a hole opening, which is an end of the communication hole adjacent to the recessed part, is spaced apart, toward the inside, from a peripheral edge portion of a recess opening, which is an end of the recessed part adjacent to the support plate part.

A physical quantity measurement device includes a physical quantity detector that detects a physical quantity of a fluid in a measurement flow path, a physical quantity processor that receives a detection result of the physical quantity detector, and a support plate part that supports the physical quantity detector and the physical quantity processor. The support plate part includes a detector support portion to which the physical quantity detector is attached, and a processor support portion that is located at a position spaced apart from the detector support portion and to which the physical quantity processor is attached. Between the detector support portion and the processor support portion, a heat transfer regulation portion is provided to regulate heat transfer from the processor support portion to the detector support portion.

A physical quantity measurement device includes a physical quantity detector that detects a physical quantity of a fluid in a measurement flow path, a physical quantity processor that receives a detection result of the physical quantity detector, and a support plate part that supports the physical quantity detector and the physical quantity processor. The support plate part includes a detector support portion to which the physical quantity detector is attached, and a processor support portion that is located at a position spaced apart from the detector support portion and to which the physical quantity processor is attached. Between the detector support portion and the processor support portion, a heat transfer regulation portion is provided to regulate heat transfer from the processor support portion to the detector support portion.

A thermal sensor device capable of maintaining measurement accuracy for a long period by suppressing plastic deformation due to thermal expansion of the heat generating resistor and reducing resistance change of the heat generating resistor, includes: a substrate having an opening; and a diaphragm having a structure in which a lower film, a heat generating resistor, and an upper film are stacked so as to bridge the opening, in which a film thickness of the lower film is larger than a film thickness of the upper film, an average thermal expansion coefficient of the lower film is larger than an average thermal expansion coefficient of the upper film, the lower film includes a plurality of films having different thermal expansion coefficients, and a film having a largest thermal expansion coefficient among the plurality of films is formed below a thickness center of the lower film.