Dual Coil Patterned Ultra‐Thin Silicon Film Enable by Double‐Sided Process

Abstract

Double‐sided microfabrication process on an ultra‐thin silicon film has rarely been attempted due to the challenges in terms of the preparation and handling of a thin film in spite of its promising fabrication potentials. Such a process allows for doubling the thin film device density or providing dual functionalities for a thin film depending on whether the front and back sides of a thin film are processed identically or distinctively. Here, a novel double‐sided thin film processing strategy is introduced by realizing a dual coil patterned ultra‐thin silicon film that is working as an actuating or energy harvesting system. Experimentally, a dual coil patterned thin film enabled using the introduced approach shows remarkably enhanced device performance when compared with a single coil patterned counterpart. Furthermore, a multiphysics simulation model is developed and the resultant modeling data validate the experimentally measured performance enhancement. Finally, the structural durability of the thin film upon cyclic loading is tested and its diverse vibration modes are investigated.

Bidirectional Droplet Manipulation on Magnetically Actuated Superhydrophobic Ratchet Surfaces

“…Thus far, our discussion has primarily focused on the cuboid magnet. However, should a cylindrical magnet be employed, the mathematical expressions for its external magnetic fields can be found in Figure S2 and the Supporting Information. , …”

“…However, should a cylindrical magnet be employed, the mathematical expressions for its external magnetic fields can be found in Figure S2 and the Supporting Information. 58,59 To derive an analytical solution for the tilting angle θ of the bSi strip, we utilize an equilibrium equation that accommodates two opposing torques acting on the bSi strip. 60 One of these torques is the elastic restoring torque T e , the magnitude of which can be expressed as…”

“…The fabrication of the ratchet surfaces leverages previously developed methods. One such method includes the ability to manipulate, flip, and transfer ultrathin silicon (UTS)a technique that proves crucial when handling the 15 μm silicon film used in this research. , Another method is the transfer printing technique, which enables the three-dimensional heterogeneous integration of bSi strips and elastomer ridges …”

“…One such method includes the ability to manipulate, flip, and transfer ultrathin silicon (UTS)�a technique that proves crucial when handling the 15 μm silicon film used in this research. 58,65 Another method is the transfer printing technique, which enables the three-dimensional heterogeneous integration of bSi strips and elastomer ridges. 66 First, as shown in Figure S9, we source UTS from the device layer of a silicon-on-insulator (SOI) wafer (Ultrasil LLC).…”