title: Precision structural engineering of self-rolled-up 3D nanomembranes guided by transient quasi-static FEM modeling.
abstract: Micro- and nanoscale tubular structures can be formed by strain-induced self-rolled-up nanomembranes. Precision engineering of the shape and dimension determines the performance of devices based on this platform for electronic, optical, and biological applications. A transient quasi-static finite element method (FEM) with moving boundary conditions is proposed as a general approach to design diverse types of three-dimensional (3D) rolled-up geometries. This method captures the dynamic release process of membranes through etching driven by mismatch strain and accurately predicts the final dimensions of rolled-up structures. Guided by the FEM modeling, experimental demonstration using silicon nitride membranes was achieved with unprecedented precision including controlling fractional turns of a rolled-up membrane, anisotropic rolling to form helical structures, and local stress control for 3D hierarchical architectures.
authors.affiliation: Department of Electrical and Computer Engineering, ‡Micro and Nanotechnology Laboratory, §Department of Mechanical Science and Engineering, and ∥National Center for Supercomputing Applications, University of Illinois at Urbana-Champaign , Urbana, Illinois 61801, United States.
authors.forename: Wen
authors.initials: W
authors.lastname: Huang
authors.forename: Seid
authors.initials: S
authors.lastname: Koric
authors.forename: Xin
authors.initials: X
authors.lastname: Yu
authors.forename: K Jimmy
authors.initials: KJ
authors.lastname: Hsia
authors.forename: Xiuling
authors.initials: X
authors.lastname: Li
keywords: Geometry engineering; finite element method; self-rolled-up nanomembrane tube; transient quasi-static