Electrostatic charges and their distribution on the charged surfaces probed by sum-frequency generation spectroscopy

Abstract

Abstract We examined the electrostatic charging states of insulating polymer surfaces using sum-frequency generation (SFG) spectroscopy. For the negatively charged polypropylene, the SFG peak amplitudes increased significantly with increasing surface potential, indicating that the electric-field formed by the electrostatic charges directly affects the SFG signal intensities. In the organic thin films stacked on top of PMMA, an increase in the SFG signal of buried PMMA is observed, indicating that the electrostatic field formed by the electrical charges is extended into the bulk direction. In addition, visualization of the location and distribution of the charges is demonstrated using the SFG intensity variations.