本論文使用五環素(Pentacene)和十三烷基駢苯衍生物(N,N’-ditridecylperylene-3,4,9,10-tetracarboxylic diimide , PTCDI-C13)組合成低電壓操作之有機互補式金屬氧化半導體(Organic Complementary Metal-Oxide-Semiconductor, O-CMOS)做為細菌感測器。
在相同細菌種類下，由高濃度至低濃度，滴至O-CMOS中PTCDI-C13薄膜電晶體的通道上，可以發現O-CMOS元件之轉換電壓偏移量會隨著細菌濃度下降而漸漸變小。特別的是，當細菌濃度降至101 CFU/ml數量級時，元件仍然可以偵測出細菌的存在，由此可知，元件靈敏度極高。此外，O-CMOS轉換電壓之偏移量和細菌濃度可以得到一線性關係。由此線性關係，可以推估未知濃度的細菌溶液達到可定量分析之元件。
由於細菌體積太大以致於無法滲入至絕緣層與主動層之間。然而，細菌的代謝物是由deoxyribonucleic acid (DNA)組成，細菌和細菌代謝物皆可使PTCDI-C13薄膜累積負電荷。此外，細菌表面會附著DNA分子，且分子大小足以滲入至絕緣層和主動層之間，使整體電荷密度提高，讓PTCDI-C13薄膜電晶體電性劇烈提升。故本研究結果提出一個獨特的概念，細菌代謝物中的DNA是影響PTCDI-C13薄膜電晶體元件電性的主要原因。

In this study, two organic semiconductors, pentacene and N, N’-ditridecylperylene-3,4,9,10-tetracarboxylic diimide (PTCDI-C13), were used to fabricate an organic complementary metal-oxide-semiconductor (O-CMOS) device on a polyimide (PI) flexible substrate to act as a bacteria sensor.
Different bacterial solutions of various concentrations were placed dropwise on the PTCDI-C13-based transistor in O-CMOS devices. We observed that the switching voltage offset of the O-CMOS device gradually decreased with decreasing concentrations of the bacterial solutions. When the bacterial concentration was lowered to the order of 101 CFU/ml, the device still showed electrical responses, indicating that it was extremely sensitive to bacteria detection. In addition, the switching voltage offsets and the bacterial concentrations show a linear relationship. Based on this linear relationship, the O-CMOS can be used to quantitatively analyze and evaluate a bacterial solution with unknown concentration.
The bacteria are too large to penetrate through the semiconductor layer to the insulating layer. However, bacterial metabolites are composed of deoxyribonucleic acid (DNA) that possesses negative charges and can attach to the surface of the bacteria. Placing the bacteria and their metabolites on the surface of the PTCDI-C13 thin film lead to the accumulation of negatively charged DNA on the surface of the film. The DNA molecules are small enough to penetrate into the interface between the insulating and active layers, thereby increasing the charge density in the conducting channel and improving electrical properties of the device. Consequently, the DNA in the bacterial metabolites can elicit electrical responses in the PTCDI-C13 thin film transistors in response to the presence of bacteria.

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