實際有機發光元件載子漂移率量測研究

The Measurement of Carrier Mobility for Real Organic Light Emitting Devices

陳建文(Jian-Wen Chen)

指導教授 ： 楊恆隆

國立臺北科技大學/機電學院/光電工程系所/碩士(2006年)

https://doi.org/10.6841/NTUT.2006.00267

摘要

本論文研究主題在於以暫態分析法 (TEL, Transient Electro-Luminescence) 為基礎而新發展的相對性量測技術應用於實際有機發光半導體元件載子漂移率的量測，將結構複雜之實際發光元件視為一整體未知特性的待測元件。分別探討兩項載子漂移率量測技術CELIV (Charge Exhausted in Linear Increasing Voltage) 與TEL進行數值模擬計算，在合理預估條件下找出此兩項量測技術適當工作範圍，驗證在工作區內理論值與近似值的誤差小於11% (對CELIV技術而言)、小於15% (對TEL技術而言)皆仍為可接受範圍。新量測法以TEL技術為基礎，分別改變串聯電阻 (R)、施加方波電壓上限 (Vf)、施加方波電壓下限 (Vi) 為實驗上三項操作變因以量測小分子紅光元件 (glass/ITO/CuPc/NPB/Alq3：DCJTB%Rubrene%/Alq3/LiF/Al)，分析其量測結果並與理論方程式fitting找出載子漂移率值，所測得之載子漂移率分別為1.30×10-4 (cm2/V•s) (以R為操作變因)、 1.56×10-4 (cm2/V•s)(以Vf為操作變因)、1.49×10-4 (cm2/V•s) (以Vi為操作變因)。此量測結果顯示此三個不同操作變因下所得之載子漂移率值有相當高的精確度。分析誤差來源合理地估算出實驗誤差範圍為5%至20%。

關鍵字

暫態分析法 ； 相對性量測 ； 有機發光半導體元件 ； 載子漂移率 ； 數值模擬 ； 誤差範圍

並列摘要

This thesis research is to study and develop a novel approach based on the transient electro-luminescence (TEL) method and the concept of relative measurement for measuring the carrier mobility of real organic light-emitting devices (OLED). The complicated OLED structure was regarded as an integral device in which its carrier mobility is to be measured during the development of the novel approach. Methods named “charge exhausted in linear increasing voltage (CELIV)” as well as TEL method were studied by computer simulation to determine the suitable range for operation under reasonable conditions. The simulation results showed that the acceptable percentage error caused by approximation is less than 11% for CELIV method and 15% for TEL method. Based on TEL method, the series resistance (R), the upper limit of step function (Vf), and the lower limit of step function (Vi) were regarded as operational factors in novel measurement approach. An OLED with structure of glass/ITO/CuPc/NPB/Alq3：DCJTB%Rubrene%/Alq3/LiF/Al was used for experimental verification. The measured carrier mobility obtained by data fitting were 1.30×10-4 (cm2/V•s) (R as operational factor)、 1.56×10-4 (cm2/V•s)( Vf as operational factor)、1.49×10-4 (cm2/V•s) (Vi as operational factor) respectively. These results revealed that the accuracy of this novel and relative measuring approach was relatively high. The percentage error during measurement was estimated between 5% and 20%.

並列關鍵字

TEL ； relative measurement ； real organic light emitting devices ； mobility ； CELIV ； simulation ； fitting ； percentage error

參考文獻

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