Mechanism that governs the electro-optic response of second-order nonlinear polymers on silicon substrates

Journal
Optical materials express  
Volume
5
Issue
8
Start Page
1653
End Page
1660
Citation
Optical Materials Express 8 (5): 1653-1660 (2015)
Publisher DOI
10.1364/OME.5.001653
Scopus ID
2-s2.0-84947799986
Publisher
OSA
We use a modified Teng-Man technique to investigate the poling induced electro-optic activity of chromophore-doped organic polymers poled on silicon substrate in a thin film sample configuration. We reveal a fundamental difference between the poling processes on silicon substrate and ITO substrate. The electro-optic activity for polymers poled on silicon substrate is reduced which we ascribe to space charge formation at the silicon - organic interface that distorts the field distribution in the polymer film during high field poling, and therefore limits the effective induced polar order. We demonstrate that the electro-optic activity on silicon substrate can be improved by inserting a 5 nm thin dielectric layer of Al2O3q between the silicon substrate and the polymer which reduces the leakthrough current during poling, thereby allowing for higher applicable poling voltages.
DDC Class
600: Technik
More Funding Information
German Research Fondation (DFG) via FOR 653