Monday, December 17, 2018

Highly Sensitive ALD SnO2 Sensors and the Role of its Thickness in Gas Sensing Capabilities


Highly Sensitive ALD SnO2 Sensors and the Role of its Thickness in Gas Sensing Capabilities Published on Dec 4, 2018
 
Authors: Akhilesh Tanneeru, Zachary Taylor, Bongmook Lee, Veena Misra Abstract: 
 
We report superior gas sensing properties of nano-layered atomic layer deposited - tin oxide thin films with room temperature operation and discuss the role of thickness on the sensing response of the films. 25, 50, 100 cycles of tin oxide ALD films have been evaluated for response with ozone gas in the concentration range of 25ppb-100ppb. At 75ppb of ozone, relevant concentration indicated for an Asthma attack, a remarkable increase in sensitivity by 22 times is seen with the 50 cycles ALD SnO2 sensor over the 100 cycles sensor and an increase of 58 times, with the 25 cycles sensor over the 50 cycles sensor. The operating power per sensor was under 200uW including the power consumed by an UV LED (385nm wavelength) used for resetting the sensors’ baseline resistances.