A Novel and Highly Sensitive Gas Flow Sensor Using a Hot Spot on YBa₂Cu₃O_7-δ Thin Films

Abstract

A novel and highly sensitive hot-wire-type flow sensor constructed of a YBa2Cu3O7-δ thin film has been fabricated. When heating voltage was applied to the sensor, a hot spot appeared and the sensor had a high sensitivity to air flow speeds of 0.04-4 m/s. Sensing characteristics have been examined for two different heating modes, constant-voltage and constant-resistance. In the constant-voltage mode, the current was proportional to the square root of the flow speed. In the constant-resistance mode, the output voltage was proportional to the fourth root of the flow speed, as is explained by the well-known King's law. In both cases, high sensitivity and good linearity were observed.

Novel sponge-like structure created in GdBa2Cu3O7Kdceramics by hot spot

“…The current is also sensitive to the gas flow around the rod, and the rod can be used as a high sensitive gas flow sensor [11]. Under low oxygen partial pressure, the current vibrates in the form of damped sinusoidal oscillation [12].…”