title: Quantitatively estimating defects in graphene devices using discharge current analysis method.
abstract: Defects of graphene are the most important concern for the successful applications of graphene since they affect device performance significantly. However, once the graphene is integrated in the device structures, the quality of graphene and surrounding environment could only be assessed using indirect information such as hysteresis, mobility and drive current. Here we develop a discharge current analysis method to measure the quality of graphene integrated in a field effect transistor structure by analyzing the discharge current and examine its validity using various device structures. The density of charging sites affecting the performance of graphene field effect transistor obtained using the discharge current analysis method was on the order of 10(14)/cm(2), which closely correlates with the intensity ratio of the D to G bands in Raman spectroscopy. The graphene FETs fabricated on poly(ethylene naphthalate) (PEN) are found to have a lower density of charging sites than those on SiO2/Si substrate, mainly due to reduced interfacial interaction between the graphene and the PEN. This method can be an indispensable means to improve the stability of devices using a graphene as it provides an accurate and quantitative way to define the quality of graphene after the device fabrication.
authors.affiliation: Center for Emerging Electronic Devices and Systems, School of Materials Science and Engineering, Gwangju Institute of Science and Technology, Oryong-dong 1, Buk-gu, Gwangju, Korea 500-712.
authors.forename: Ukjin
authors.initials: U
authors.lastname: Jung
authors.affiliation: Center for Emerging Electronic Devices and Systems, School of Materials Science and Engineering, Gwangju Institute of Science and Technology, Oryong-dong 1, Buk-gu, Gwangju, Korea 500-712.
authors.forename: Young Gon
authors.initials: YG
authors.lastname: Lee
authors.affiliation: Center for Emerging Electronic Devices and Systems, School of Materials Science and Engineering, Gwangju Institute of Science and Technology, Oryong-dong 1, Buk-gu, Gwangju, Korea 500-712.
authors.forename: Chang Goo
authors.initials: CG
authors.lastname: Kang
authors.affiliation: Department of Nanobio Materials and Electronics, Gwangju Institute of Science and Technology, Oryong-dong 1, Buk-gu, Gwangju, Korea 500-712.
authors.forename: Sangchul
authors.initials: S
authors.lastname: Lee
authors.affiliation: Department of Nanobio Materials and Electronics, Gwangju Institute of Science and Technology, Oryong-dong 1, Buk-gu, Gwangju, Korea 500-712.
authors.forename: Jin Ju
authors.initials: JJ
authors.lastname: Kim
authors.affiliation: Center for Emerging Electronic Devices and Systems, School of Materials Science and Engineering, Gwangju Institute of Science and Technology, Oryong-dong 1, Buk-gu, Gwangju, Korea 500-712.
authors.forename: Hyeon June
authors.initials: HJ
authors.lastname: Hwang
authors.affiliation: Center for Emerging Electronic Devices and Systems, School of Materials Science and Engineering, Gwangju Institute of Science and Technology, Oryong-dong 1, Buk-gu, Gwangju, Korea 500-712.
authors.forename: Sung Kwan
authors.initials: SK
authors.lastname: Lim
authors.affiliation: 1] Center for Emerging Electronic Devices and Systems, School of Materials Science and Engineering, Gwangju Institute of Science and Technology, Oryong-dong 1, Buk-gu, Gwangju, Korea 500-712 [2] Department of Nanobio Materials and Electronics, Gwangju Institute of Science and Technology, Oryong-dong 1, Buk-gu, Gwangju, Korea 500-712.
authors.forename: Moon-Ho
authors.initials: MH
authors.lastname: Ham
authors.affiliation: 1] Center for Emerging Electronic Devices and Systems, School of Materials Science and Engineering, Gwangju Institute of Science and Technology, Oryong-dong 1, Buk-gu, Gwangju, Korea 500-712 [2] Department of Nanobio Materials and Electronics, Gwangju Institute of Science and Technology, Oryong-dong 1, Buk-gu, Gwangju, Korea 500-712.
authors.forename: Byoung Hun
authors.initials: BH
authors.lastname: Lee