具堆疊介電層五苯環紫外光電晶體之研究

The study of pentacene-based ultraviolet phototransistors with a stacked dielectric layer

林郁竣(Yu-Chun Lin)

指導教授 ： 蘇水祥 ； 橫山明聰

義守大學/電機資訊學院/電子工程學系/碩士(2015年)

https://doi.org/10.6343/ISU.2015.00267

摘要

本研究以豬血清白蛋白(PSA)與PMMA/SiO2為閘極介電層研製紫外光有機光電晶體，在未照光下比較其電特性，以PSA為閘極介電層結構之光電晶體具飽和電流、載子遷移率、臨界電壓分別為-28.1 µA、2.7 cm2/Vs、-7.53 V，而以PMMA/SiO2為閘極介電層結構之飽和電流、載子遷移率、臨界電壓分別為-2.09 µA、0.126 cm2/Vs、-9.2 V。經紫外光照射後，以PSA為閘極介電層之光電晶體特性衰退，以PMMA/SiO2為閘極介電層之光電晶體對應之電特性提升到-4.4 µA、0.28 cm2/Vs、-8.4 V，故選用PMMA/SiO2堆疊閘極介電層研究紫外光有機光電晶體之特性。
有機光電晶體製作時調變pentacene主動層厚度為35、70、100及150 nm，使用10 W/cm^2、365 nm紫外光光源照射光電晶體並觀察電特性，調變照射時間探討pentacene主動層對於紫外光的吸收率，研究紫外光有機光電晶體之光敏值、光響應、通道電阻。當pentacene主動層厚度為100 nm時，其光生成載子最多使通道電阻值最低，紫外光有機光電晶體具較佳特性，其光敏值、光響應與通道電阻分別為3、0.21與1.8x106 Ω。

關鍵字

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並列摘要

In this study, alternatively using albumin from porcine serum (PSA) and poly (methyl methacrylate) (PMMA)/SiO2 as a gate dielectric layer fabricated each different ultraviolet organic phototransistors (UV-PTs). The electrical characteristics under illumination and in the dark of UV-PTs are discussed in this study. Employing PSA as a gate dielectric layer in UV-PTs, the electrical characteristics which shows the output current (IDS) is -28.1 μA, field-effect mobility (μ) is 2.7 cm2/Vs, and the threshold voltage (VT) is -7.53 V, respectively. In the meanwhile, the other UV-PTs with a gate dielectric of PMMA/SiO2 show IDS is -2.09 μA, μ is 0.126 cm2/Vs, and VT is -9.2 V. Comparing with the two devices after UV illumination, experimental results reveal that the UV-PTs with a PSA gate dielectric is decay significantly. However, the UV-PTs with a PMMA/SiO2 gate dielectric shows IDS raising to -4.4 μA, μ to 0.28 cm2/Vs, and VT to -8.4 V. Therefore, the study adopts PMMA/SiO2 as a stacked gate dielectric layer to develop UV-PTs characteristics.
UV-PTs are fabricated by varying the pentacene active layer thickness of 35 nm, 70 nm, 100 nm and 150 nm. Their electrical characteristics are observed under illumination of a 365 nm ultraviolet light source at 10 W/cm2. The absorbance of active layer was discussed by vary irradiating time. Moreover, the photosensitivity, responsibility and channel resistance of UV-PTs’ were characterized. When the active layer, pentacene, thickness was 100 nm, the UV-PTs had the lowest channel resistance owing to increased photo-generated carriers and demonstrated an optimized photosensitivity of 3, responsibility of 0.21 and channel resistance of 1.8 x106 Ω, respectively.

並列關鍵字

none

參考文獻

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