以介電泳動定位由金奈米粒子修飾之氧化鋅奈米線之感測器應用

Abstract

在本論文中，我們運用介電泳動技術製備了空橋式氧化鋅（ZnO）奈米線的感測器元件，然後利用金奈米粒子的修飾，研究含金奈米粒子修飾與不含金奈米粒子的元件，對於乙醇濃度與濕度變化的電性響應。首先，我們在矽基板上沉積了絕緣層二氧化矽，然後利用標準的黃光微影技術在基板上定義出金屬電極的位置。隨後，我們使用電子束蒸鍍機鍍上鈦做為金屬電極，接著利用介電泳的方法，將奈米線精確定位在指定的電極上，形成了空橋結構，再使用電子束蒸鍍機鍍上金奈米粒子，最終成功製備出利用金奈米粒子修飾的氧化鋅奈米線感測器。 經由上述製程，我們對單純的氧化鋅和經過金奈米粒子修飾的氧化鋅奈米線元件在紫外光照射的環境下進行改變乙醇濃度環境時的電流響應和反應時間的量測，量測後發現有金奈米粒子的樣品擁有更大的響應及較短的回復時間。另外，也針對這兩種不同的樣品，改變環境相對濕度，同樣進行電流響應和反應時間的量測。量測結果也展現了經過金奈米粒子修飾的樣品在響應上優勢，最後，與文獻進行比較和討論。

In this research work, we employed dielectrophoretic deposition techniques to fabricate sensors using bridged zinc oxide (ZnO) nanowires. Subsequently, through modification with Au nanoparticles, we investigated the electrical responses to variations in ethanol concentration and humidity for devices with and without Au nanoparticle modifications. Initially, we deposited a SiO2 insulating layer on a silicon substrate and defined the positions of the metal electrodes using standard photolithography techniques. Then, we used an electron-gun evaporator to deposit titanium as the metal electrodes. Subsequently, utilizing dielectrophoretic methods, we precisely positioned nanowires on specified electrodes, forming a bridged structure. Au nanoparticles were then deposited also using an electron-gun evaporator. Finally, we successfully fabricated sensors based on Au nanoparticle-modified ZnO nanowires. After the aforementioned processes, we conducted measurements on the electrical responses and recovery times of pure ZnO and Au nanoparticle-modified ZnO nanowire devices under varying ethanol concentrations in an environment exposed to ultraviolet light. The results revealed that samples with Au nanoparticles exhibited larger responses and shorter recovery times. Additionally, we performed measurements on these two different samples under varying relative humidity conditions, analyzing electrical responses and recovery times. The measured results demonstrated the advantages of Au nanoparticle-modified devices. Finally, we compared and discussed our findings with the literature.