Amorphous Si TFTs on plastically deformed spherical domes

There is a growing interest in the design and fabrication of flexible and rugged electronics particularly for large-area displays and sensor arrays. In this work, we describe the fabrication of amorphous silicon (a-Si:H) thin film transistors (TFTs) on a Kapton' substrate which can be permanently deformed into a spherical cap shape. This level of strain would crack uniform a-Si:H device films. To prevent fractures in our TFT structure. the silicon and silicon nitride layers of the TFTs are patterned to create isolated device islands. After deformation, these brittle islands can remain crackfree, and the TFTs achieve comparable device behavior despite average strain in the substrate in excess of 5%. (C) 2002 Elsevier Science B.V. All rights reserved.