Plasma-Enhanced Atomic Layer Deposition of Silicon Nitride Thin Film at 100oc Using Novel Silicon Precursors

Abstract

Recently, the demand for moisture barrier has been increasing as the encapsulation layers of organic electronic devices, such as organic light-emitting diode (OLED) display, organic solar cells, and organic thin-film transistors. Dielectric thin films prepared by plasma-enhanced chemical vapor deposition (PECVD), hot-wire CVD, and atomic layer deposition (ALD) at low temperatures lower than 150°C have been investigated as the moisture barrier. Among them, the multilayered thin structure composed of aluminum oxide or silicon nitride prepared by ALD showed the best results [1,2]. In the present work, we prepared silicon nitride thin films by plasma-enhanced ALD (PEALD) at 100°C using novel silicon precursors, 1,3-di-iso-propylamino-4,4-dimethylcyclodisilazane (CSN-2) and bis-(di-methylamino-dimethylsilyl)- trimethylsilyl amine (DTDN-2H2), and investigated the properties of the deposited films, such as growth rate per cycle, composition, density, wet etch rate, and water vapor permeability. The effects of deposition temperature and plasma condition on the barrier properties were also discussed. [1] F. Nehm, ACS Appl. Mater. Interfaces, 7 (2015) 22121. [2] A.-M. Andringa, et al., ACS Appl. Mater. Interfaces, 7 (2015) 22525. Fig.1. The FTIR spectrum of silicon nitride thin films prepared by PEALD at 100°C using CSN-2 as the silicon precursor. Figure 1