以糖類嵌段共聚物開發生質光電膜與光記憶體應用

Abstract

由於無機電子元件的資源有限，故過去十幾年已有不少學者開發高品質有機元件。其中，生質有機材料的獨特光學和電學性質吸引了許多學者的廣泛關注。近年，眾多文獻發表利用不同分子結構和嵌段共聚物設計之糖基材料在光記憶體上的應用，而溶劑退火可以實現高分子的特殊形貌，並對於元件的記憶性能也會有顯著的影響。

首先，在這篇論文的第二章我們使用含有芳烴的麥芽糖基嵌段共聚物作為記憶體材料。在此良好的環境下，我們利用溶劑退火的方法來造成薄膜中的分子流動。通過調整溶劑比例以及退火時間，成功地得到更有趣的形貌。此外，我們也發現發光的芳烴會影響元件的形貌以及記憶能力，導致不同的記憶行為。接著，在第三章我們在DNTT的光記憶體中使用糖-聚苯乙烯作為光電層。為了證明元件機制，我們研究了糖類嵌段共聚物的光學性質。採用微波退火的方式，以微波輻射作為熱源來得到高度規整性以及糖的奈米分散性。高度規整的形貌能夠使電流增強，並可在低電壓和長時間內保持高電流。

最後，本論文主要研究生質有機材料於光記憶體上的應用，並探討分子結構和奈米分散性如何影響記憶行為。我們提升了退火的方法，實現嵌段共聚物的高度規整形貌，提供了元件的記憶特性，以揭示它們在綠色電子元件應用中的潛力。

Because of the limited resource for inorganic electronic devices, a new trend of high-quality organic devices has been developed in the past few decades. With their unique optical and electrical properties, bio-based materials have attracted extensive attention of numerous researchers. By utilizing sugar-based materials with different molecular structure and block copolymer designs, diverse memory behavior of green electret-based phototransistor memory is reported. Furthermore, solvent-mediated annealing methods were used to achieve well-ordered morphology of the thin films, which can significantly influence the memory performance of the devices. Firstly, maltose-based block copolymers with pendent arenes were employed as polymer electret (Chapter 2). Herein, favorable environment to trigger the molecular motion in the thin films were conducted by solvent vapor annealing treatment. More ordered morphologies were successfully obtained adjusting the solvent ratio and annealing time. Moreover, the photoluminescent arenes greatly affect the morphology and charge-trapping capability of the memory devices, resulting in varied memory behaviors of the devices. Secondly, we introduced sugar-block-polystyrene as photoactive dielectric layer in DNTT-based phototransistor memory (Chapter 3). The optical properties of the block copolymers were thoroughly investigated to elucidate the photoexcitation event during the photowriting operation. In addition, by using microwave radiation as the heat source during the annealing process resulted in highly organized sugar nanodomains. The high degree of morphological orientation resulted in enhance photocurrent which can be retained at low operating voltages and over extended durations. In addition, the device imitates the synaptic behavior of biological synapse with low-energy-consumption under ultralow operating voltage. In conclusion, this thesis predominantly focuses on incorporating bio-based materials into memory devices and explores how their molecular structure and nanoscaled morphology impact the memory behaviors. Enhanced annealing treatments were performed to achieve ordered and oriented morphologies of the studied block copolymers. Besides, this thesis also provides the memory characterizations of studied memory devices to unravel their potential in green electronic device application.