Silicon nitride deposited by laser assisted plasma enhanced chemical vapor deposition for next generation organic electronic devices

Abstract

Deposition of stoichiometric silicon nitride without damage and stress at low temperature using plasma enhanced chemical vapor deposition (PECVD) is an important issue in the application to various areas such as microelectronics, micro-electromechanical system (MEMS), etc. In this study, the effects of laser assistance during PECVD (LAPECVD) of silicon nitride on the physical and chemical characteristics of deposited Si3N4 film were investigated. The LAPECVD assisted by 193 nm laser at 80 °C showed higher deposition ratescompared to PECVD due to the enhanced dissociation of the reactant gases. In addition, the stoichiometric ratio of N/Si and the residual stress of the deposited silicon nitride film were improved. When the silicon nitride was directly deposited on the organic light emitting diode (OLED) for thin film passivation, no electrical damage was observed for LAPECVD possibly due to the coverage of a thin silicon nitride layer on the OLED surface by laser assisted deposition while conventional PECVD showed a damage of the device due to ion bombardment by direct exposure to plasma. We believe the LAPECVD system can be used for various next-generation microelectronic industries where high quality film deposition with minimized damage during PECVD at low temperature is required.