光和臭氧在石墨烯元件上的特性探討

The effect of photon and ozone on transport properties of graphene devices

林柏勳(Po-shin Lin)

指導教授 ： 謝雅萍

國立中正大學/工學院/機電光工程研究所/碩士(2012年)

並列摘要

Abstract
Graphene, a monoatomic sheet of carbon, has great potential for use as transparent conductive electrode (TCE) owing to its high optical transmittance and conductivity. To be competitive to existing TCE materials, however, its sheet resistance has to be minimized.
We here present a detailed study on the effects of doping and defects on the sheet resistance of CVD synthesized graphene. Controlled exposure of a graphene device to UV ozone serves as a model system for the doping induced changes to the electrical transport in graphene.
Two distinctive regimes of doping levels were observed: In the low doping region, the increase in charged carriers caused by ozone adsorption exceeds the mobility deterioration associated with the addition of charged impurities and consequently the sheet resistance decreases. In the high exposure region, the defect induced drop in mobility dominates the sheet resistance as confirmed by Raman spectroscopy and the sheet resistance is found to increase.
By carefully tuning the UV exposure, the sheet resistance could be decreased by 70%. This study offers new insights on the achievable performance of graphene based TCEs.
Keywords: Graphene, UV ozone, transparent conductive electrode (TCE)

並列關鍵字

graphene ； UV ozone ； transparent conductive electrode

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