Nanoscale Variable-Area Electronic Devices: Contact Mechanics and Hypersensitive Pressure Application

Abstract

Nanomembranes (NMs) are freestanding structures with few-nanometer thickness and lateral dimensions up to the microscale. In nanoelectronics, NMs have been used to promote reliable electrical contacts with distinct nanomaterials, such as molecules, quantum dots, and nanowires, as well as to support the comprehension of the condensed matter down to the nanoscale. Here, we propose a tunable device architecture that is capable of deterministically changing both the contact geometry and the current injection in nanoscale electronic junctions. The device is based on a hybrid arrangement that joins metallic NMs and molecular ensembles, resulting in a versatile, mechanically compliant element. Such a feature allows the devices to accommodate a mechanical stimulus applied over the top electrodes, enlarging the junctions' active area without compromising the molecules. A model derived from the Hertzian mechanics is employed to correlate the contact dynamics with the electronic transport in these novel devices denominated as variable-area transport junctions (VATJs). As a proof of concept, we propose a direct application of the VATJs as compression gauges envisioning the development of hypersensitive pressure pixels. Regarding sensitivity (∼480 kPa −1 ), the VATJ-based transducers constitute a breakthrough in nanoelectronics, with the prospect of carrying its sister-field of molecular electronics out of the laboratory via integrative, hybrid organic/inorganic nanotechnology.

Charge Transport and Gradient Doping in Nanostructured Polypyrrole Films for Applications in Photocurrent Generation

“…The material layers are engineered to form nm-thick Au/PPy/Au vertical heterojunctions, as demonstrated in our previous works. 14,38,39 required to maintain charge neutrality. Commercially available liquid pyrrole (Py) (Alfa Aesar 98%) was evaporated through the cell from a round bottom flask by heating it to 373 K. As the Py monomers get in contact with the solution, polymerization occurs at the surface of the droplet, forming a PPy filmsee film A in Figure 1a(iii).…”

“…18 Accordingly, we have synthesized 20 and 120 nm thick films that were sandwiched by a pair of Au electrodes. The heterojunction platform, based on nanomembranes (NM), 14,38,39 was employed to provide reliable electrical contacts with the active nanomaterials. The PPy electrical conduction was evaluated as a function of the applied voltage (V) and the reservoir temperature (T).…”

Reorganization Energy upon Controlled Intermolecular Charge‐Transfer Reactions in Monolithically Integrated Nanodevices

“…[34][35][36] Additionally, nCap monolithic integration spares the use of either liquid metal electrodes or scanning probe tips, allowing reliable fabrication of real-life molecular devices that can be operated in different electromagnetic fields, temperatures, pressures, among other external conditions. [37][38][39] In the literature, one may find exciting examples of using the nanomembrane-origami technology to fabricate various monolithically-integrated devices featuring organic/ inorganic hybrid functions. [40][41][42][43] As a validating target for our experimental paradigm, we fabricate nCaps employing copper-phthalocyanine (CuPc) nanometer-thick films.…”

High‐Performance Ultrathin Molecular Rectifying Diodes Based on Organic/Inorganic Interface Engineering

“…traditional inorganic electronic components -or even replace them -comes from the possibility of creating systems that display a high degree of sophistication. [4][5][6] Flexible devices processed by low-temperature routes and reduced production costs are some to mention a few. [7] As organic materials and devices reach the nanoscale, organic/inorganic interfaces become a fundamental counterpart, being responsible for several functionalities.…”