具奈米線-聚塞吩網絡之複合式薄膜電晶體

Abstract

有機半導體材料因為在發光二極體、太陽能電池、電子紙，射頻識別標籤的應用範圍具有極大潛力而備受關注。所有這些電子產品都可以用非常低的成本、較低的製程溫度，且很容易地利用大面積製造技術應用在可撓性基板上。具有較高的場效應載子遷移率和適於溶液態操作特性的共軛高分子半導體（例如，區域規則性聚塞吩）已被應用在有機薄膜電晶體中。由於有機薄膜電晶體的性能與聚合物薄膜的結構排列息息相關，可用於溶液化製程的自組裝區域規則性聚-3-己基塞吩（P3HT），具有顯著擇優取向的有序結構，使得共軛平面垂直於基材表面，而這似乎非常有助於載子傳輸，P3HT因此也成為最受矚目的材料之一。然而儘管材料的功能和處理技術有最新的進展，有機薄膜電晶體的元件壽命和載子遷移率，使得它在更廣範圍的應用上仍然受到限制。本論文研究一種具有機半導體和平行排列的奈米線網絡的複合式薄膜電晶體，利用最近發展的拉伸接觸轉印技術將 奈米線陣列，整合於旋轉塗佈的半導體高分子層下，形成如奈米複合材料的主動通道來進行載子傳輸。與單純有機高分子元件相比，此複合式薄膜電晶體在載子遷移率(提高到四倍)和空氣中穩定性上達到正向提升的作用。

Semiconducting organic materials have their great potential in applications ranging from, solar cells, LED, RFID tags, and E-papers. It can realize large area fabrication on flexible substrate at low cost. Conjugated semiconducting polymers with high carrier mobility and solution process ability characteristics (e.g., regioregular polythiophene) have been introduced into the fabrication process of organic thin film transistors (OTFTs). Since the OTFTs performance strongly depends on the structural arrangement and ordered orientation of π-conjugated planes perpendicular to the substrate surface of the polymer thin film. Self-organized regioregular poly-3-hexylthiophene (rr-P3HT) has above favorable properties which seem to be very helpful in carrier transport and also has remarkable solution process ability. Despite recent advancements in material functionality and processing technologies, OTFTs are somewhat limited in terms of device lifetime and mobility, which hinder their adoption on a wider scale. This work demonstrated a series of hybrid thin film transistors (TFTs) with a network of organic semiconductors and parallel aligned nanowires. Silicon nanowire arrays, assembled by a recently developed stretched contact printing technique, are embedded in a layer of a spun-coat semiconducting polymer, forming a nanocomposite active channel for electrical conduction. The hybrid TFTs have revealed an enhancement in charge carrier mobility (up to four times) and air stability compared to those of the pristine polymer host.