The pre-high-level temperature modulation: gas detection strategy to improve the response speed of semiconductor sensor

With the rapid development of the Internet of Things, gas detection has become an important part of ensuring industrial process and information security. In recent years, dynamic temperature modulation mode has been widely used in semiconductor gas sensors to improve their selectivity. This mode has no definition of response time so far and is not optimized from the perspective of response speed. In fact, the response speed of dynamic temperature modulation mode is relatively slow. In the Internet of Things, there is an urgent need for efficient and fast gas detection equipment. Hereon, based on the dynamic response characteristics, the response time is divided into type response time and concentration response time. When using triangular wave heating voltage based on SnO2 sensor, it shows excellent type response speed and poor concentration response speed. Then, according to the response mechanism of the sensor, the concentration response speed of the sensor is improved by applying pre-high-level to the sensor. Finally, the response mechanism of dynamic temperature modulation is explored, and on this basis, the influence on response speed is explained about oxygen accumulation and high reactive oxygen species produced by pre-high-level heating voltage.