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Abstract This work reports a three‐dimensional (3D) radio frequency L−C filter network enabled by a CMOS‐compatible two‐dimensional (2D) fabrication approach, which combines inductive (L) and capacitive (C) self‐rolled‐up membrane (S‐RuM) components monolithically into a single L−C network structure, thereby greatly reducing the on‐chip area footprint. The individual L−C elements are fabricated in‐plane using standard semiconductor processing techniques, and subsequently triggered by the built‐in stress to self‐assemble and roll into cylindrical air‐core architectures. By designing the planar structure geometry and constituent layer properties to achieve a specific number of turns with a desired inner diameter when the device is rolled up, the electrical characteristics can be engineered. The network layouts of the L and C components are also reconfigurable by selecting appropriate input, output, and ground contact routing topographies. The devices demonstrated here operate over the range of ≈1−10 GHz. Their area and volume footprints are ≈0.09 mm2and ≈0.01 mm3, respectively, which are ≈10× smaller than most of the comparable conventional filter designs. These S‐RuM‐enabled 3D microtubular L−C filter networks represent significant advancement for miniaturization and integration of passive electronic components for applications in mobile connectivity and other frequency range.
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Self-assembled microtubular electrodes for on-chip low-voltage electrophoretic manipulation of charged particles and macromolecules
Abstract On-chip manipulation of charged particles using electrophoresis or electroosmosis is widely used for many applications, including optofluidic sensing, bioanalysis and macromolecular data storage. We hereby demonstrate a technique for the capture, localization, and release of charged particles and DNA molecules in an aqueous solution using tubular structures enabled by a strain-induced self-rolled-up nanomembrane (S-RuM) platform. Cuffed-in 3D electrodes that are embedded in cylindrical S-RuM structures and biased by a constant DC voltage are used to provide a uniform electrical field inside the microtubular devices. Efficient charged-particle manipulation is achieved at a bias voltage of <2–4 V, which is ~3 orders of magnitude lower than the required potential in traditional DC electrophoretic devices. Furthermore, Poisson–Boltzmann multiphysics simulation validates the feasibility and advantage of our microtubular charge manipulation devices over planar and other 3D variations of microfluidic devices. This work lays the foundation for on-chip DNA manipulation for data storage applications.
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- Award ID(s):
- 1807526
- PAR ID:
- 10363476
- Publisher / Repository:
- Nature Publishing Group
- Date Published:
- Journal Name:
- Microsystems & Nanoengineering
- Volume:
- 8
- Issue:
- 1
- ISSN:
- 2055-7434
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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