基于电极质量负载的超灵敏超高频AlScErN声表面波传感器研究

声表面波(SAW)传感器因其微型化及高灵敏性在毒气痕量检测、生物分子识别、微质量超敏探测等领域具有广阔应用前景。发展超高频SAW器件是进一步提升其检测灵敏度至单分子水平的关键。然而，目前超高频SAW传感器研发还面临声波传播区灵敏度低、纳米叉指换能器加工难、高声速压电薄膜机电耦合系数小等瓶颈。针对上述问题，项目拟开展基于电极质量负载的超灵敏超高频AlScErN声表面波传感器研究：1)提出基于电极质量负载超灵敏的SAW敏感新机制，在高频下大幅提高灵敏度；2)开发智能自适应迭代算法结合(lift-off+离子束刻蚀)的新工艺，突破超高频SAW纳米叉指的极端制造；3)提出Sc、Er共掺AlN压电材料新思路，探索Sc、Er共掺压电响应机制，摸索其生长机理，实现大机电耦合系数高声速新材料的可调控生长。项目的实施将发展出10GHz以上超高频SAW传感器并展示其在毒气痕量检测和微质量超灵敏探测应用。

Surface acoustic wave (SAW) sensors have wide spread applications in the field of trace detection of nerve and erosive agents, biomolecular recognition and ultra-sensitive detection of micro mass, etc., due to its miniaturization and high sensitivity. The development of ultra-high frequency SAW devices is the key to greatly improve the sensing sensitivity of SAW sensors to the level of single molecule. However, at present, the research of ultra-high frequency SAW sensor faces some bottlenecks such as low sensitivity during the acoustic wave propagation area, manufacturing difficulty of the nanoscale interdigital transducer and low electromechanical coupling coefficient of piezoelectric film with high sound velocity. To solve these problems, the applicant proposed the research on ultra-sensitive and ultra-high frequency SAW sensors based on electrode mass loading effect with the AlScErN film. 1) A new SAW sensitivity mechanism based on electrode mass loading effect is proposed, which can greatly improve the sensitivity at high frequency. 2) A new electron beam manufacturing method is developed combining an intelligent adaptive iterative algorithm with improved lift-off process, which can make a breakthrough in the manufacturing the nanoscale interdigital transducer. 3) The new material of AlScErN film is proposed to obtain large electromechanical coupling coefficient and high sound velocity, and the doping and growth mechanism of AlScErN piezoelectric films will be clarified. The implementation of this project will develop ultra-high frequency SAW sensors (above 10GHz), as well as application on the detection of chemical warfare agent, and ultra-sensitive detection of micro mass.