Effects of Oxide-trapped Charges and Interface Traps in Organic Self-assembled Monolayer/Silicon Systems due to Local Current Injection

Abstract

The charge trapping characteristics of silicon (Si) substrates covered with a self-assembled monolayer (SAM) were studied using on a local biasing method with Kelvin-probe force microscopy. A hexadecyl SAM (HD-SAM) on a Si substrate, in which the molecules were covalently bonded to the Si substrate, was found to have no charge trapping sites at its monolayer/Si interface while an ocatadecylsilyl SAM (ODS-SAM) on a Si substrate, in which a thin oxide layer was inserted between the molecules and the Si substrate, showed a distinct charge trapping behavior. The alkyl monolayer directly fixed on Si is promising as a very thin insulating layer in Si microelectronics.