網版印刷壓電能量擷取器及其轉印於軟性基板之觸覺感測器之研製

The Studies of Piezoelectric Energy Harvesters by Screen Printing Method and Transfer Piezoelectric to Flexible Substrates as Tactile Sensor

高銘揚(Ming-Yang Gao)

指導教授 ： 吳文中

國立臺灣大學/工學院/工程科學及海洋工程學研究所/碩士(2017年)

https://doi.org/10.6342/NTU201704060

摘要

隨著人口老化，多數已開發國家已邁入高齡化社會，伴隨穿載式電子裝置技術逐漸的成熟，穿載裝置追踪慢性患者的遠距醫療監測市場也將持續增加，可望降低整體醫療成本。然而目前健康監測之穿戴式裝置的市場受到阻礙，有著感測器準確度與供電來源兩大問題，因此本論文的目標是製作具有高力電轉換效率的可撓式元件，可將其應用於穿戴式裝置的感測器或能量擷取器上。
為了達成目標，元件將結合高力電轉換效率的鋯鈦酸鉛(PZT)與可撓性的PET塑膠基板，由於PET無法承受製程上PZT熱處理的高溫，因此將透過新穎的轉印技術解決此問題，首先使用網版印刷法將PZT厚膜沉積於不鏽鋼暫時基板上，經過高溫熱處理後，PZT厚膜將會收縮並從暫時基板上些許分離，分離的原因是緩衝層與PZT層熱膨脹係數的差異，最後將PZT黏著於PET目標基板後，撕除暫時基板，完成具有柔軟且高品質的壓電元件。
本論文成功製作兩種尺寸相似的懸臂量式壓電能量擷取器，其不同點為兩者之基板與PZT層之厚度，製作於65 μm不鏽鋼基板上的元件不須經過轉印技術，壓電層厚度約為21.4 μm，在0.5 g加速度、62.9 Hz共振環境下，量測到開迴路電壓為7.19 Vp-p、在最佳阻抗下輸出功率為2.71 μW；製作於100 μm PET基板上的元件必需過轉印技術製成，壓電層厚度為17.3 μm，在0.5 g加速度、70.4 Hz共振環境下，量測到開路電壓為4.42 Vp-p、在最佳阻抗下輸出功率為1.80 μW。最後針對於PET元件進行彎曲測試與脈搏量測，彎曲測試中給予一端頻率為1.15 Hz、位移量1 mm 之變形，產生的開迴路電壓為3.15 Vp-p，脈搏量測結果顯示波形呈現規律的脈搏波形。
雖然本論文中能量擷取器的功率仍不足以驅動穿載裝置，但已成功使用簡易且適合量產的轉印技術將PZT壓電厚膜轉移至PET基板，並且此元件同時擁有良好的壓電特性及機械柔軟性，可適用於貼合人體皮膚的觸覺感測器。

關鍵字

鋯鈦酸鉛 ； 壓電厚膜 ； 塑膠基板 ； 網版印刷 ； 轉印技術 ； 壓電能量擷取器 ； 觸覺感測器

並列摘要

As increasing of aging population, all major developed countries are going into aging societies. With the technologies of smart wearable devices getting matured, the market demand of remote healthcare using smart wearable devices keeps increasing and hope to reduce overall medical expenses. The obstacles of smart wearable devices for health monitor are preciseness and power sources. Therefore, the objective of this study is to develop high-performance and flexible piezoelectric devices which can be accuracy tactile sensors or energy harvesters.
In order to have higher strain, the plastic substrates are needed. The sintering process for piezoelectric (PZT) film is typically over 800 °C which is not suitable for plastic substrates. Therefore, the development of PZT films on low temp resist substrate is important. We proposed a newly designed process in transfer high-performance PZT film on plastic substrate by screen printing with transfer technique.
The d31 mode energy harvester based on stainless steel substrate was fabricated. The PZT thickness is 21.4 μm. The device has 1.80 μW maximum output power and 4.42 Vp-p open-circuit output voltage under an excitation frequency of 62.9 Hz and 0.5 g excitation acceleration level. The d31 mode energy harvester based on PET substrate was fabricated by transferring technique. The PZT thickness is 17.3 μm. The device has 2.71 μW maximum output power and 7.19 Vp-p open-circuit output voltage under an excitation frequency of 70.4 Hz and 0.5 g excitation acceleration level. The banding test has the result of 3.15 Vp-p open-circuit output voltage under an excitation frequency of 1.15 Hz with 1 mm displacement. Moreover, the tactile sensor was made and measure with human pulses successfully. These results show the potential of smart wearable devices with accuracy tactile sensors by simply transferring techniques.

並列關鍵字

PZT ； thick films ； flexible substrate ； screen printing ； transfer technique ； piezoelectric energy harvester ； tactile sensor

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