Nozzleless jetting of droplets with different jetting angles is a crucial requirement for 2D and 3D printing/bioprinting applications, and Rayleigh mode surface acoustic waves (SAWs) could be a potential technique for achieving this purpose. Currently, it is critical to vary the jetting angles of liquid droplets induced by SAWs and control the liquid jet directions. Generally, the direction of the liquid jet induced by SAWs generated from a bulk piezoelectric substrate such as LiNbO 3 is along the theoretical Rayleigh angle of ∼22°. In this study, we designed and manufactured thin-film SAW devices by depositing ZnO films on different substrates (including silicon and aluminium) to realize a wide range of jetting angles from ∼16° to 55° using propagating waves generated from one interdigital transducer. We then systematically investigated different factors affecting the jetting angles, including liquid properties, applied SAW power and SAW device resonant frequency. Fin...

中文翻译：

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基于薄膜的表面声波可实现大范围的液滴喷射角度

对于2D和3D打印/生物打印应用，以无喷嘴方式喷射具有不同喷射角度的液滴是至关重要的要求，而瑞利模式表面声波（SAW）可能是实现此目的的一种潜在技术。当前，至关重要的是改变由声表面波引起的液滴的喷射角度并控制液体的喷射方向。通常，由块状压电基板（如LiNbO 3）产生的SAW引起的液体喷射方向沿理论瑞利角约为22°。在这项研究中，我们设计和制造了薄膜SAW器件，方法是在一个不同的基板（包括硅和铝）上沉积ZnO膜，以利用一个叉指式换能器产生的传播波实现从约16°至55°的大范围喷射角。然后，我们系统地研究了影响喷射角度的不同因素，包括液体性质，施加的SAW功率和SAW器件谐振频率。鳍...