Self-Assembled Single-Crystal Silicon Circuits on Plastic

• Published in: Proceedings of the National Academy of Sciences - PNAS Vol. 103; no. 38; pp. 13922 - 13927
• Main Authors: Stauth, Sean A., Parviz, Babak A.
• Format: Journal Article
• Language: English
• Published: United States National Academy of Sciences 19.09.2006; National Acad Sciences
• Subjects: Alloys; Binding sites; Crystals; Electronics; Electrons; Glycols; Photoresists; Physical Sciences; Plastics; Resistors; Self assembly; Silicon; Substrates; Transistors
• ISSN: 0027-8424; 1091-6490
• DOI: 10.1073/pnas.0602893103

We demonstrate the use of self-assembly for the integration of freestanding micrometer-scale components, including single-crystal, silicon field-effect transistors (FETs) and diffusion resistors, onto flexible plastic substrates. Preferential self-assembly of multiple microcomponent types onto a common platform is achieved through complementary shape recognition and aided by capillary, fluidic, and gravitational forces. We outline a microfabrication process that yields single-crystal, silicon FETs in a freestanding, powder-like collection for use with self-assembly. Demonstrations of self-assembled FETs on plastic include logic inverters and measured electron mobility of 592 cm²/V-s. Finally, we extend the self-assembly process to substrates each containing 10,000 binding sites and realize 97% self-assembly yield within 25 min for 100μm-sized elements. High-yield self-assembly of micrometer-scale functional devices as outlined here provides a powerful approach for production of macroelectronic systems.