應用於能量擷取的軟性壓電材料

Abstract

由於低功率互補式金氧半半導體超大型積體電路技術發展，使得電路的功耗需求降低，積體電路的能量需求已經降低至數十微瓦的程度，由環境獲取能量來驅動低功率的遠端感測器成為可能，促使了無線感測網路應用的發展。並隨著個人化電子產品的流行，高齡化社會對於醫療電子的需求，由人體產生的能量提供電子產品能源，且藉由無線感測器與多電源的結合，可以增加產品的使用壽命且降低耗能。一個體重52公斤的人，每次行走足部可以提供67 W的功率，以廣為應用；但在人體可彎曲處，如:手肘彎曲、手指運動、呼吸時胸口的起伏等處的應用卻非常地少。 本論文中，我們提出了一種新穎的材料以期達到在人體或是其他可撓曲處的能量擷取，此乃為一軟性壓電材料，由PDMS及PZT所結合而成，結合二者的材料特性。摻雜不同重量比例的PZT粉末至PDMS溶液中，再利用塗佈機形成材料，試片每片為20 mm × 20mm的正方形，定義上下電極，並用X光晶格繞射儀、電滯曲線量測機台、阻抗分析儀與壓電係數量測機台等等做測量，來得到期材料特性。 本材料經過量測後，不同摻雜比例的PZT粉末的PDMS/PZT具有相近的量測結果。本PDMS/PZT 具有和PZT塊材一致的材料組成；其頑固電場落在3.15×104至4.81×105 V/m；殘餘極化量落在5.96×10-5 至1.99×10-3 μC/cm2，以及其壓電係數落在3.9 至13.9 pC/N。

Due to the low power CMOS VLSI technology, the power consumption is reduced to about a few tens of microwatts to enable the development of applications such as wireless sensor networks or personal health monitoring. Therefore, it becomes feasible to power portable devices by scavenging the ambient energy. A 52kg person’s footfall can generate 67W power, and this is widely used. But for the bent places, such as the elbow, fingers and breathing band are seldom applied. In this thesis, the fabrication process and measurement results of PDMS/PZT are presented. PDMS/PZT is composed by both PDMS and PZT, and can be applied in the bent of human body or other places. Mix different ratio of PZT powder into PDMS, then the mixture is fabricated by spinner. Every sample of PDMS/PZT is 20 mm × 20 mm with electrodes. The X-ray diffraction, hysteresis, impedance analysis and piezoelectric coefficient of the PDMS/PZT sample are measured. The different mixing ratios of PDMS/PZT have similar measurement results. The material of PDMS/PZT is composed as same as PZT bulk. The coercive field is ranged from 3.15×104 to 4.81×105 V/m; the remanent polarization is ranged at 5.96×10-5 to 1.99×10-3 μC/cm2; the piezoelectric coefficient is ranged from 3.9 to 13.9 pC/N.