AVS 61st International Symposium & Exhibition
    2D Materials Focus Topic Thursday Sessions
       Session 2D+EM+MI+MN+NS+SS+TF-ThA

Paper 2D+EM+MI+MN+NS+SS+TF-ThA11
Use of XPS for Device Characterization

Thursday, November 13, 2014, 5:40 pm, Room 310

Session: Novel Quantum Phenomena in 2D Materials 
Presenter: Sefik Suzer, Bilkent University, Turkey
Authors: P. Aydogan, Bilkent University, Turkey
E.O. Polat, Bilkent University, Turkey
C. Kocabas, Bilkent University, Turkey
S. Suzer, Bilkent University, Turkey
Correspondent: Click to Email
A noncontact chemical and electrical measurement technique of XPS is utilized to investigate a number of devices made of graphene. The main objective of the technique is to trace chemical and location specific surface potential variations as shifts of the XPS peak positions under operating conditions. Devices consisting of graphene; (i) acting as a simple resistive element between two gold electrodes, (ii) a semiconducting sheet controlled by a back-gate, and (iii) between the source and the drain metal electrodes in a full transistor geometry, have been analyzed by recording the Au4f of the metal electrodes, the C1s of the graphene layer, and the O1s (or N1s) peaks of the silicon oxide (or nitride) of the substrate. The advantage of this technique is its ability to assess element specific surface electrical potentials of devices under operation based on the deviations of the core level peak positions in surface domains/structures. Detection of the variations in electrical potentials and especially their responses to various stimuli gives unprecedented information about the chemical nature as well as the location of structural and/or other types of defects as a result of doping, oxidation, reduction, etc.