近年可撓式電子元件蓬勃發展，元件基板多以塑膠材料為主，雖然塑膠基板在可撓性上有非常好的表現，但有耐化學性較差、熔點低不耐高溫以及導熱率差等缺點，導致元件操作時所產生的熱能無法快速排除，因此限制了以塑膠為基板的元件發展。
本實驗為了改善上述問題，將高熔點、熱導率佳的矽基板濕蝕刻至能彎曲的厚度，並將擁有優秀的熱導、機械、光學特性的還原氧化石墨烯(Reduced graphene oxide, rGO)作為光感測器的主動層。實驗進一步透過具有強吸光能力和高電洞遷移率的黑磷量子點(Black phosphorus quantum dots, BPQDs)來提升還原氧化石墨烯薄膜的光學特性，完成以黑磷量子點修飾之可撓式還原氧化石墨烯/矽光感測器。
根據實驗結果顯示，薄化後的矽基板擁有可撓性且製成元件在彎曲1000次後仍保有優異的紫外光檢測能力。此外rGO/Si元件在使用BPQDs摻雜後，電流有顯著的提升，說明BPQDs確實增加捕捉光子的效率進而產生出更多的電子-電洞對。實驗規劃不同還原氧化石墨烯與黑磷量子點的比例最佳化元件特性，其中以rGO:BPQDs=3:1比例混和製成的元件表現為最佳，在外加偏壓5V及55.3 mW/cm2的功率密度下光響應度(Responsivity)從原先rGO/Si元件的1.46 A/W提升到16.9 A/W，而光探測率(Detectivity)也達到2.13*1010 Jones。綜合以上分析，本實驗成功製備了矽基可撓式紫外光感測器，並透過黑磷量子點提升光感測器的特性，此技術可應用於更多可撓式元件，開啟可撓式系統的另一頁。

In recent years, flexible electronic devices fabricated on plastic substrates have developed vigorously. Although plastic substrates have excellent flexibility in terms of flexibility, they have poor chemical resistance, low melting point, inability to withstand high temperatures, and poor thermal conductivity. The heat energy generated during the operation of the devices cannot be quickly removed, thus limiting the development of devices using plastic as the substrate.
To solve the above problems, the silicon substrate with a high melting point and good thermal conductivity was used as substrates in the study. Thin Si substrates constructed by wet etched can be bent, and reduced graphene oxide (rGO) with excellent thermal conductivity, mechanical and optical properties was served as the active layer of the photodetector. The experiment further improved the optical properties of the reduced graphene oxide film through black phosphorus quantum dots (BPQDs) with strong light absorption ability and high hole mobility. A flexible rGO/Si photodetector decorated with BPQDs was therefore realized.
According to the experimental results, the thin silicon substrates are flexible and the devices retain excellent UV detection capability even after bending 1000 times. In addition, the current of rGO/Si devices is significantly increased after doping with BPQDs, which indicates that BPQDs do increase the efficiency of capturing photons and thus produce more electron-hole pairs. Different ratios of reduced graphene oxide to black phosphorus quantum dots were designed to optimize the device characteristic. Among these photodetectors, the rGO:BPQDs=3:1 photodetector exhibited the best performance. Compared with of the original rGO/Si photodetector, the responsivity was increased from 1.46 A/W to 16.9 A/W at 5V bias voltage. The power density and the detectivity reached 55.3 mW/cm2 and 2.13*1010 Jones, respectively. The above analysis shows that flexible BPQDs/rGO photodetector has successfully prepared on a silicon-based substrate and the performance is enhanced, which can be applied to more flexible devices and open another page of flexible systems.

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