Large-area single-crystal graphene grown on a recrystallized Cu(111) surface by using a hole-pocket method

AbstractPower devices (PD) are ubiquitous elements of the modern electronics industry that must satisfy the rigorous and diverse demands for robust power conversion systems that are essential for emerging technologies including Internet of Things (IoT), mobile electronics, and wearable devices. However, conventional PDs based on “bulk” and “single-crystal” semiconductors require high temperature (> 1000 °C) fabrication processing and a thick (typically a few tens to 100 μm) drift layer, thereby preventing their applications to compact devices, where PDs must be fabricated on a heat sensitive and flexible substrate. Here we report next-generation PDs based on “thin-films” of “amorphous” oxide semiconductors with the performance exceeding the silicon limit (a theoretical limit for a PD based on bulk single-crystal silicon). The breakthrough was achieved by the creation of an ideal Schottky interface without Fermi-level pinning at the interface, resulting in low specific on-resistance Ron,sp (< 1 × 10–4 Ω cm2) and high breakdown voltage VBD (~ 100 V). To demonstrate the unprecedented capability of the amorphous thin-film oxide power devices (ATOPs), we successfully fabricated a prototype on a flexible polyimide film, which is not compatible with the fabrication process of bulk single-crystal devices. The ATOP will play a central role in the development of next generation advanced technologies where devices require large area fabrication on flexible substrates and three-dimensional integration.

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Shape-Controlled, Single-Crystal Gold Surface Nanostructures

10.26434/chemrxiv.9956450 ◽

2019 ◽

Author(s):

Sasan V. Grayli ◽

Xin Zhang ◽

Dmitry Star ◽

Gary Leach

Keyword(s):

Single Crystal ◽

Electroless Deposition ◽

Near Field ◽

Critical Role ◽

Deposition Process ◽

Local Fields ◽

Metal Nanostructures ◽

Large Area ◽

Device Applications ◽

Shape Controlled

Size, shape and crystallinity play a critical role in the wavelength-dependent optical responses and plasmonic local near-field distributions of metallic nanostructures. While their enhanced local fields can drive new and useful chemical and physical processes, the ability to fabricate shape-controlled single-crystal metal nanostructures and position them precisely on substrates for device applications represents a significant barrier to harnessing their greater potential. Here, we describe a novel electroless deposition process in the presence of anionic additives that yields additive-specific, shape-controlled, single-crystal plasmonic Au nanostructures on Ag(100) and Au(100) substrates. Deposition of Au in the presence of SO42- ions results in the formation of smooth Au(111)-faceted square pyramids that show large surface enhanced Raman responses. The use of halide additives such as Cl- and Br- that interact strongly with (100) facets produces highly textured hillock-type structures characterized by edge and screw-type dislocations (Cl-), or flat platelet-like features characterized by large area Au(100) terraces with (110) step edges (Br-). Use of additive combinations provides structures that comprise characteristics derived from each additive including new square pyramidal structures with dominant Au(110) facets (SO42-and Br-). Finally we demonstrate that this bottom-up electroless deposition process, when combined with top-down lithographic patterning methods, can be used to position shape-controlled, single-crystal Au nanostructures with precise location and orientation on surfaces. We anticipate that this approach will be employed as a powerful new tool to tune the plasmonic characteristics of nanostructures and facilitate their broader integration into device applications.

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Amorphous thin-film oxide power devices operating beyond bulk single-crystal silicon limit

10.21203/rs.3.rs-221354/v1 ◽

2021 ◽

Author(s):

Yuki Tsuruma ◽

Emi Kawashima ◽

Yoshikazu Nagasaki ◽

Takashi Sekiya ◽

Gaku Imamura ◽

...

Keyword(s):

Thin Film ◽

Single Crystal ◽

Flexible Substrate ◽

Single Crystal Silicon ◽

Bulk Single Crystal ◽

Next Generation ◽

Power Devices ◽

Large Area ◽

Crystal Silicon ◽

Amorphous Thin Film

Abstract Power devices (PD) are ubiquitous elements of the modern electronics industry that must satisfy the rigorous and diverse demands for robust power conversion systems that are essential for emerging technologies including Internet of Things (IoT), mobile electronics, and wearable devices. However, conventional PDs based on “bulk” and “single-crystal” semiconductors require high temperature (>1000°C) fabrication processing and a thick (typically a few tens to 100 μm) drift layer1, thereby preventing their applications to compact devices2, where PDs must be fabricated on a heat sensitive and flexible substrate. Here we report next-generation PDs based on “thin-films” of “amorphous” oxide semiconductors with the performance exceeding the silicon limit (a theoretical limit for a PD based on bulk single-crystal silicon3). The breakthrough was achieved by the creation of an ideal Schottky interface without Fermi-level pinning at the interface, resulting in low specific on-resistance Ron,sp (<1×10-4 Ωcm2) and high breakdown voltage VBD (~100 V). To demonstrate the unprecedented capability of the amorphous thin-film oxide power devices (ATOPs), we successfully fabricated a prototype on a flexible polyimide film, which is not compatible with the fabrication process of bulk single-crystal devices. The ATOP will play a central role in the development of next generation advanced technologies where devices require large area fabrication on flexible substrates and three-dimensional integration.

Download Full-text