Room temperature direct bonding and debonding of polymer film on glass wafer for fabrication of flexible electronic devices

Abstract

Thin film transistors (TFTs) are playing the critical role in the flexible electronics, and for its fabrication on the polyimide (PI) films it is necessary to fix the PI film on glass wafer and to delaminate the PI film after TFT process. However the current method to bond and debond PI films to glass wafers contains complicated and costly processes. In this study we succeeded in easy bonding and debonding PI films on glass wafers directly by using Si or Cu intermediate layer with Fe ultra-thin layer at room temperature. The Si or Cu layer was deposited on polyimide films and glass wafers by Ar ion beam sputtering, and then film and wafer ware brought into contact and pressed in high vacuum. The bonding strength can be controlled by the bonding condition such as intermediate layer thickness and Fe nano-adhesion layers. Additionally, we made TFT on polyimide films after bonding and evaluated the electric property of the TFT. The polyimide film can be peeled off from glass wafer after TFT process by a load not strong enough to damage the film, and it didn't result in deteriorating the TFT performance.