Gulnizkij Nikolai, Gerlach Gerald
Solid-State Electronics Laboratory, Technische Universität Dresden, 01062 Dresden, Germany.
Micromachines (Basel). 2020 Jun 3;11(6):569. doi: 10.3390/mi11060569.
Energy-autonomous bistable threshold sensor switches have the potential to reduce costs because they do not need any electrical energy supply for monitoring physical quantities, such as relative humidity. In previous work, a bistable beam-like sensor switch with switching hysteresis was manufactured from sheet metal and a partially coated water vapor-sensitive hydrogel (poly(vinyl alcohol)/poly(acryl acid)). Based on the beam theory, a corresponding mechanical model was developed. However, bending plates should be used instead of bending beams to separate the humidity to be measured from the electrical contacts. For this reason, this work deals with the development and realization of a mechanical model based on the plate theory to describe the deflection of a silicon bimorph bending plate partially coated with hydrogel that swells with increasing humidity. For implementing a switching hysteresis a plasma-enhanced chemical vapor deposition silicon dioxide (SiO) layer is used, which was deposited and structured on top of the silicon plate. The hydrogel layer itself is patterned on the surface of the bending plate using a stamp technique. To validate the mechanical model, the switching hysteresis of the miniaturized sensor switch was measured optically by a camera measurement device.
能量自主双稳态阈值传感器开关具有降低成本的潜力，因为它们在监测诸如相对湿度等物理量时无需任何电能供应。在先前的工作中，一种具有开关滞后特性的双稳态梁状传感器开关是由金属薄板和部分涂覆的对水蒸气敏感的水凝胶（聚乙烯醇/聚丙烯酸）制成的。基于梁理论，开发了相应的力学模型。然而，应该使用弯曲板而不是弯曲梁，以便将待测湿度与电触点分开。因此，这项工作致力于基于板理论开发和实现一个力学模型，以描述部分涂覆有水凝胶且随湿度增加而膨胀的硅双压电晶片弯曲板的挠度。为了实现开关滞后特性，使用了等离子体增强化学气相沉积二氧化硅（SiO）层，并将其沉积在硅板顶部并进行结构化处理。水凝胶层本身则通过压印技术在弯曲板表面进行图案化处理。为了验证力学模型，通过相机测量设备对小型化传感器开关的开关滞后特性进行了光学测量。
