CHEMORESISTOR TYPE GAS SENSOR HAVING A MULTI-STOREY ARCHITECTURE

화학저항 유형의 가스 센서가 설명된다. 센서는 절연층 상에 제공된 가스 센싱층, 센싱층과 접촉하여 제공되는 측정 전극들; 및 센싱층을 자외선 광에 노출시키도록 동작 가능한 자외선 광 소스를 포함한다. 가스 센서는 특히 자외선 광의 인가 시작 후 첫번째 초 동안 측정 전극들을 통해 취해진 측정치들의 분석에 의해 자외선 광의 인가 시작시에 센싱층의 과도 응답을 결정하도록 구성된 분석 유닛을 더 포함한다. A multi-storey gas sensor is constructed by stacking chemoresistor type gas sensing elements (CH1,CH2) and providing holes through each sensing element, at least in the region where the sensing layer (52) is formed, so that gas can pass from one sensing element to the next, through the sensing layers (52). A rich set of measurements can be obtained, enabling the characterisation/analysis of a gas under test with increased accuracy and/or the tailoring of the measurements to the particular gas-sensing application: notably by selecting appropriate combinations of materials for the sensing layers of the different gas-sensing elements and by varying the operating conditions applicable to the different gas-sensing elements notably by: taking measurements at respective times when different combinations of sensing layers in the stack are activated, at times when given sensing layers are heated to different temperatures or according to different heating profiles, and/or when selected sensing layers are exposed to UV light. Sensor sensitivity and selectivity can be increased by applying UV pulses of controlled duration. For miniaturization, and increased measurement-speed, each sensing element (CH1,CH2) may have a micro-hotplate architecture.