Ramola R C, Negi Sandhya, Rawat Mukesh, Singh R C, Singh Fouran
Department of Physics, HNB Garhwal University, Badshahi Thaul Campus, Tehri Garhwal 249 199, India.
Department of Physics, Guru Nanak Dev University, Amritsar 143005, India.
ACS Omega. 2021 Apr 22;6(17):11660-11668. doi: 10.1021/acsomega.1c00984. eCollection 2021 May 4.
The high thermal conductivity, high electron mobility, the direct wide band gap, and large exciton binding energy of zinc oxide (ZnO) make it appropriate for a wide range of device applications like light-emitting diodes, photodetectors, laser diodes, transparent thin-film transistors, and so forth. Among the semiconductor metal oxides, zinc oxide (ZnO) is one of the most commonly used gas-sensing materials. The gas sensor made of nanocomposite ZnO and Ga-doped ZnO (ZnO:Ga) thin films was developed by the sol-gel spin coating method. The gas sensitivity of gallium-doped ZnO thin films annealed at 400, 700, and 900 °C was studied for ethanol and acetone gases. The variation of electrical resistance of gallium-doped ZnO thin films with exposure of ethanol and acetone vapors at different concentrations was estimated. Ga:ZnO thin films annealed at 700 °C show the highest sensitivity and shortest response and recovery time for both ethanol and acetone gases. This study reveals that the 5 at. % Ga-doped ZnO thin film annealed at 700 °C has the best sensing property in comparison to the film annealed at 400 and 900 °C. The sensing response of ZnO:Ga thin films was found higher for ethanol gas in comparison to acetone gas.
氧化锌（ZnO）具有高导热性、高电子迁移率、直接宽带隙和大激子结合能，使其适用于多种器件应用，如发光二极管、光电探测器、激光二极管、透明薄膜晶体管等。在半导体金属氧化物中，氧化锌（ZnO）是最常用的气敏材料之一。采用溶胶 - 凝胶旋涂法制备了由纳米复合ZnO和Ga掺杂ZnO（ZnO:Ga）薄膜制成的气体传感器。研究了在400、700和900℃退火的镓掺杂ZnO薄膜对乙醇和丙酮气体的气敏性。估算了不同浓度乙醇和丙酮蒸汽暴露下镓掺杂ZnO薄膜电阻的变化。在700℃退火的Ga:ZnO薄膜对乙醇和丙酮气体均表现出最高的灵敏度以及最短的响应和恢复时间。该研究表明，与在400℃和900℃退火的薄膜相比，在700℃退火的5原子% Ga掺杂ZnO薄膜具有最佳的传感性能。发现ZnO:Ga薄膜对乙醇气体的传感响应高于丙酮气体。
