以銀奈米粒子當緩衝層及主動層摻混絕緣材料應用於P型有機薄膜電晶體元件探討

Effects of silver nanoparticle buffer layer and active layer blended insulating material on characteristics of P-type organic thin film transistors

陳榮靖(Jung-Ching Chen)

指導教授 ： 許佳振、何正榮

國立中正大學/工學院/光機電整合工程研究所/碩士(2013年)

摘要

本文主要探討加入銀奈米粒子(Silver nanoparticles，Ag-NPs)及摻混絕緣材料(PMMA或PS)對有機半導體電晶體(OTFTs)元件性能之影響。本研究使用粒徑大小約10 nm的銀奈米粒子，將其放置於SiO2介電層與主動層之間作為緩衝層(Buffer layer)，先探討不同濃度比例的銀奈米粒子當緩衝層對OTFT元件電性影響，進一步摻混絕緣材料(PMMA或PS)於主動層內，觀察OTFT元件電性。本研究中也探討此主動層摻混絕緣材料(PMMA或PS)在不同比例下之薄膜特性。結果顯示，介電層表面因有奈米粒子，能夠增強介電層電場效應，吸引更多載子，提升元件飽和電流，而主動層因摻混絕緣材料(PMMA或PS)，雖會造成載子遷移率些微下降，但摻混後之元件在空氣中的穩定度提升，因而使開關電流比(on/off ratio)提升。故加入銀奈米粒子及摻混PMMA或PS絕緣材料對有機半導體電晶體元件的載子遷移率和開關電流比均有明顯提升。

關鍵字

P3HT摻混PMMA ； 有機薄膜電晶體 ； P3HT摻混PS

並列摘要

This study aims to investigate both effects of surface, negatively charged silver nanoparticles (Ag-NPs) and the active layer blended with insulating material (PMMA or PS) on the performance enhancement of organic thin-film transistors (OTFTs). A buffer layer consisting of Ag-NPs, with diameters around 10 nm, was introduced between the SiO2 dielectric layer and the P3HT active layer. First, the effect of particle concentration of Ag-NPs on the device characteristics was studied, the influences of the active layer blended with insulating polymers (PMMA or PS) was then investigated. In addition, we also explored the effect of the amount of the insulation polymer on the resulting device characteristics. Results show that the existence of the NPs on the dielectric layer was able to enhance the strength of the electric field which led to attract more hole carriers at the dielectric-active layer interface. Consequently, an increase of the saturation source-drain current, a higher mobility, can be obtained. The blending of the insulating polymer in the active layer caused a slight reduction in device mobility. However, the device is more stable in the ambient and a substantial increase of on/off ratio was observed. Therefore, with simultaneously introducing Ag-NPs on the surface of the dielectric layer and blending the insulating polymer in the active layer, both mobility and on/off ration are able to be significantly improved.

並列關鍵字

P3HT/PS ； P3HT/PMMA ； OTFT

參考文獻

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