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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.

We propose an advanced architecture of an electrically controlled nanofluidic sluice for a DNA-based data storage device. Our device comprises embedded gold electrodes to which appropriate voltages are applied for effective capture, hold, and release of chimeric DNA strands. Electrostatic potential profiles across the device obtained via multiphysics simulation that solves for the Nernst−Planck−Poisson equation show nanoscale sluice operation for two device architectures: one with planar electrodes and the other with buried arch electrodes in combination with planar electrodes. Our simulations show that apart from its compatibility with complementary metal oxide−semiconductor (CMOS) technology, the device architecture with buried arch electrodes can effectively store the chimeric DNA strands without any leakage in conjunction with release on demand while offering the capability for large-scale integration.

Aluminum nitride (AlN) continues to kindle considerable interest in various microelectromechanical system (MEMS)related fields because of its superior optical, mechanical, thermal, and piezoelectric properties. In this study, we use magnetron sputtering to tailor intrinsic stress in AlN thin films from highly compressive (−1200 MPa) to highly tensile (+700 MPa), with a differential stress of 1900 MPa. By monolithically combining the compressive and tensile ultrathin AlN bilayer membranes (20−60 nm) during deposition, perfectly curved three-dimensional (3D) architectures are spontaneously formed upon dry-releasing from the substrate via a 3D MEMS approach: the complementary metal-oxide-semiconductor (CMOS)-compatible strain-induced self-rolled-up membrane (S-RuM) method. The thermal stability of the AlN 3D architectures is examined, and the curvature of S-RuM microtubes and helical structures as a function of the cumulative membrane thickness and stress are characterized experimentally and simulated using a finite-element physiomechanic method. By combining AlN with various materials such as metal (Cu) and silicon nitride (SiN x ), AlN-based hybrid S-RuM microtubes with diameters as small as ∼6 μm are demonstrated with a near-unity yield (∼99%). Compared with other stressed thin films for S-RuMs, including PECVD SiN x , magnetron-sputtered AlN-based S-RuMs show better structural controllability and versatility, probably due to the high Young's modulus and stress uniformity. This work establishes the sputtered AlN thin film as a superior stress-configurable S-RuM shell material for high-performance applications in miniaturizing and integrating electronic components beyond those based on other materials such as SiN x . In addition, for the first time, a single-crystal Al 1−x Sc x N/AlN bilayer grown by molecular beam epitaxy is successfully rolled-up with the diameter varying from ∼9 to 14 μm, paving the way for 3D tubular Al 1−x Sc x N piezoelectric devices.