Ultra‐Confined Catalytic Growth Integration of Sub‐10 nm 3D Stacked Silicon Nanowires Via a Self‐Delimited Droplet Formation Strategy

Abstract

Fabricating ultrathin silicon (Si) channels down to critical dimension (CD) <10 nm, a key capability to implementing cutting‐edge microelectronics and quantum charge‐qubits, has never been accomplished via an extremely low‐cost catalytic growth. In this work, 3D stacked ultrathin Si nanowires (SiNWs) are demonstrated, with width and height of Wnw = 9.9 ± 1.2 nm (down to 8 nm) and Hnw = 18.8 ± 1.8 nm, that can be reliably grown into the ultrafine sidewall grooves, approaching to the CD of 10 nm technology node, thanks to a new self‐delimited droplet control strategy. Interestingly, the cross‐sections of the as‐grown SiNW channels can also be easily tailored from fin‐like to sheet‐like geometries by tuning the groove profile, while a sharply folding guided growth indicates a unique capability to produce closely‐packed multiple rows of stacked SiNWs, out of a single run growth, with the minimal use of catalyst metal. Prototype field effect transistors are also successfully fabricated, achieving Ion/off ratio and sub‐threshold swing of >106 and 125 mV dec−1, respectively. These results highlight the unexplored potential of versatile catalytic growth to compete with, or complement, the advanced top‐down etching technology in the exploitation of monolithic 3D integration of logic‐in‐memory, neuromorphic and charge‐qubit applications.

Growth Control of In-Plane Silicon Nanowires via Catalyst Size-Dependent Laser Heating for High-Performance Electronics

“…To address the self-localization challenge, we have developed an in-plane solid–liquid–solid (IPSLS) growth strategy in our previous study, − where the indium (In) catalyst droplets move along a predesigned guiding edge and absorb a hydrogenated amorphous Si (a-Si:H) layer to produce SiNW arrays, as illustrated in Figure a. The as-grown SiNWs have been widely applied in field effect transistors (FETs), − logic, sensing, , and NEMS devices,. , Since the growth temperature in IPSLS mode is only required at the droplet level, we recently developed a self-selected laser-droplet-heating strategy to elevate temperature for the in-plane growth of high-quality SiNWs, where the leading In droplets show much stronger absorption to infrared laser (808 nm) than those of the surrounding a-Si:H and glass or silicon wafer. Thanks to the direct heating of the leading droplets, the quality of the as-grown SiNWs has been proven to be equivalent to those produced with high-temperature (>600 °C) environmental heating.…”

Inverse Design of Nanophotonic Devices Using Generative Adversarial Networks with the Sim-NN Model and Self-Attention Mechanism

“…With the improvement of nanofabrication technology [ 1 , 2 ] and the demand for high-performance nanophotonic devices, the footprint of these devices is greatly reduced for high integration density. Nanophotonic devices are widely used in imaging [ 3 ], optical computing [ 4 ], medical diagnosis [ 5 , 6 ], etc.…”

Lorentz Force-Actuated Bidirectional Nanoelectromechanical Switch with an Ultralow Operation Voltage

“…Moreover, in view of further size miniaturization for a higher integration density, the footprint of the NW-cantilevers can be readily scaled down in size by at least 20-fold, as shown for example in Figure S6. In fact, the diameter of the IPSLS SiNWs can be readily controlled to <20 nm, 55 leaving plenty of room for the formation of smaller and more delicate cantilever arms, catering to specific needs in functional design. Also, the suspension of the NW can be accomplished via selective dry etching of the targeted underlying regions.…”