Object size effect on the contact potential difference measured by scanning Kelvin probe method

¹ Institute of Solid State Physics, University of Latvia, Kengaraga st. 8, 1063 Riga, Latvia
² G. Liberta Innovative Microscopy Center, Daugavpils University, Parades street 1, 5401 Daugavpils, Latvia

Corresponding author: boris.polyakov@cfi.lu.lv

Received: 7 December 2009
Revised: 10 May 2010
Accepted: 25 May 2010
Published online: 7 July 2010

Abstract

Contact potential difference (CPD) was measured by macroscopic Kelvin probe instrument and scanning Kelvin probe microscope on Al, Ni and Pt on ITO substrates at ambient conditions. CPD values measured by scanning Kelvin probe microscope and macroscopic Kelvin probe are close within the error of about 10–30% for large studied objects, whereas scanning Kelvin probe microscope signal decreases, when the object size becomes smaller than 1.4 μm. CPD and electric field signals measured using many-pass technique allowed us to estimate the influence of electrostatic field disturbance, especially, in the case of small objects.