在低溫下的石墨烯氧化物半導體異質結構其光響應度變化

Photoresponsivity of graphene oxide semiconductor heterostructure at low temperature

王仁煜(Jen-Yu Wang)

指導教授 ： 陳正中

國立清華大學/理學院/物理學系/碩士(2018年)

摘要

石墨烯的高透光率在光學元件中擁有極大的優勢，做為光偵測器的發展也引起了重大關注。在這份工作中，我們研究以環境溫度為100 K至280 K、光源波長為425 nm、565 nm、635 nm，與光源強度作為變因，量測石墨烯氧化物半導體異質結構的閘極電壓與光電流的關係。數據顯示，樣品在飽和電流區的光電流約正比於發光強度，且光電流為暗電流的106倍，有非常大的光/暗電流比。在溫度250 K時，光響應度為12 mA/W，高於以其他材料做為閘極的光偵測器，並與其他使用石墨烯做為透明閘極的光偵測器有相近的光響應度。而當溫度為150 K，能進一步提高8倍的光響應度，達到96 mA/W。

關鍵字

石墨烯 ； 透明閘極 ； 金屬氧化物場效電晶體 ； 光偵測器 ； 凡得瓦力異質結構 ； 庫倫阻力

並列摘要

The transparent electrodes have great advantages in optoelectronic devices, and the graphene-based photodetector has also attracted significant attention. In our work, the relationship between the gate voltage and the photocurrent of the graphene oxide semiconductor heterostructure was studied by taking the temperature(100 K–280 K), the wavelength of the light source(425, 565, 635 nm), and the intensity of the light source as parameters. The data shows that the photocurrent in the saturation current region is approximately proportional to the luminescence intensity, and the photocurrent is approximately 106 times the dark current. At room temperature, the photoresponsivity is 12 mA/W, higher than the photodetector with other materials as the gate, and similar to other photodetectors using graphene as a transparent gate. The photoresponsivity can be further up to 96 mA/W , by 8 times at 150 K.

並列關鍵字

graphene ； transparent gate ； metal oxide semiconductor field-effect transistor ； photodetector ； Van der Waals force heterostructure ； coulomb drag

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