Articles you may be interested inModeling stress development and hydrogen diffusion in plasma enhanced chemical vapor deposition silicon nitride films submitted to thermal cycles Methods of producing plasma enhanced chemical vapor deposition silicon nitride thin films with high compressive and tensile stress Organic light emitting diodes (OLEDs) are attractive candidates for flexible display and lighting panels due to their high contrast ratio. However, the materials in an OLED are oxidized by very small quantities of moisture. Therefore, flexible OLEDs require flexible, thin-film, encapsulation. The authors introduce a set of three techniques for measuring the solubility and diffusion coefficient of water in a permeation barrier layer that is a SiO 2 -silicone hybrid made by plasma enhanced chemical vapor deposition. The techniques are secondary ion mass spectrometry, and measurements of electrical capacitance and of film stress. The measurements were carried out on samples exposed to water or steam at temperatures between 65 and 200 C. From the resulting values of water solubility, diffusion coefficient, and their thermal activation energies, the authors calculate the time one monolayer of water will take to permeate through the bulk of the film. For a 3 lm thick film held at 38 C and 90% relative humidity, the time is 13 years.

Water diffusion through a single-layer barrier is measured with Secondary Ion Mass Spectrometry, electrical capacitance, and mechanical film stress. The time taken for one monolayer of water molecules permeate into the OLED is defined as the lifetime. Extrapolated to T = 38°C and 90% relative humidity, a 3μ μm thick barrier is predicted to seal for 13 years.