All hot wire chemical vapor deposition low substrate temperature transparent thin film moisture barrier

Abstract

We deposited a silicon nitride/polymer hybrid multilayer moisture barrier for flexible electronics in a hot wire chemical vapor deposition process, entirely below 100 °C. We were able to reach a water vapor transmission rate (WVTR) as low as 5×10−6 g/m2/day at a temperature of 60 °C and a relative humidity of 90% for a simple three-layer structure consisting of two low-temperature silicon nitride (SiNx) layers and a polymer layer in between. This WVTR is low enough for organic and polymer devices. In a second experiment it is investigated how the yield of our samples increases with the number of SiNx layers, while keeping the total SiNx thickness constant. Cross sectional scanning electron microscopy images of degraded samples reveal a high structural robustness of our multilayers.