Low Power Consumption Microheater Platform Integrated Gas Sensor Design Using Anodic Aluminum Oxide Template

Abstract

Demands for detecting and monitoring hazardous, toxic, and flammable gases are increasing in both of industrial and domestic environments. Among various types of gas sensor, the semiconductor gas sensors are promising candidate for mobile gas monitoring platforms due to high performances and low cost [1]. The semiconductor gas sensors use conductometric change by redox reaction between oxygen ions and target gases, which requires high temperature. Microheater platforms have been researched to get high performance semiconductor gas sensors [2]. However, the microheater platforms form suspended structures to reduce heating power consumption, which reduce long-term stability [3]. In this research, anodic aluminum oxide (AAO) based microheater was designed for low-power consumption and high-stability gas sensor. Due to nanoscale air pores, anodic aluminum oxide has low heat conductivity and high thermal efficiency [4]. The heating power consumption of the fabricated microheater platform was controlled to 27mW, and the temperature was 250℃. The gas sensing response of WO3 deposited on AAO showed extremely high response to NO2 gas exposure (Rgas/Rair = 536 to 5 ppm NO2).