We have successfully observed the change in indium–gallium–zinc–oxide (IGZO) gas sensor sensitivity
by controlling the light emitting diode (LED) power under the same gas concentrations. The light inten-sity dependence of sensor properties is discussed. Different LED intensities obviously affected the gas
sensor sensitivity , which decays with increasing LED intensity. High LED intensity decreases not only
gas sensor sensitivity but also the response time (T 90), response time constant ( s res) and the absorption
rate per second. Low intensity irradiate d to sensor causes high sensitivity, but it needs larger response
time. Similar results were also observed in other kinds of materials such as TiO 2. According to the results,
the sensing properties of gas sensors can be modulated by controlling the light intensity.
2015 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND