Thomas Paul Feist

Transparent hybrid inorganic/organic barrier coatings for plastic organic light-emitting diode substrates

We have developed a coating technology to reduce the moisture permeation rate through a polycarbonate plastic film substrate to below 1×10−5g∕m2∕day using plasma-enhanced chemical vapor deposition. Unlike other ultrahigh barrier (UHB) coatings comprised of inorganic and organic multilayers, our UHB coating comprises a graded single hybrid layer of inorganic and organic materials. Hardness and modulus of the inorganic and the organic materials are tailored such that they are similar to those of typical glass-like materials and thermoplastics, respectively. In this barrier structure, the composition is periodically modulated between the inorganic and the organic materials, but instead of having distinctive interfaces between two materials, there are “transitional” zones where the coating composition changes continuously from one material to another. Our UHB coating also has superior visible light transmittance and color neutrality suitable for the use of display and lighting device substrates.

A Transparent, High Barrier, and High Heat Substrate for Organic Electronics

The use of plastic film substrates for organic electronic devices promises to enable new applications, such as flexible displays and conformal lighting, and a new low-cost paradigm through high-volume roll-to-roll fabrication. Unfortunately, presently available substrates cannot yet deliver this promise because of the challenge in achieving the required combination of optical transparency, impermeability to water and oxygen, mechanical flexibility, high-temperature capability, and chemical resistance. Here, we describe the development and performance of a plastic substrate comprising a high heat polycarbonate film combined with a unique transparent coating package that is aimed at meeting this challenge.

Experimental and analytical characterization of the mechanical performance of disks

The present study is directed towards understanding and improving the mechanical performance of plastic substrates for optical disks under vibration loading. Finite element analysis was conducted to obtain transfer functions relating the properties of the disk material with the vibration performance. An experimental test setup was assembled to measure the vibration response of disks and validate the predictions of the analytical model.