Query: rolled-up nanotechnology for nanomembrane

Candidate papers:

abstract: Monolithic capacitors operating at radio frequencies (RF) serve as critical components in integrated circuits for wireless communication. Design and fabrication innovations for high capacitance density RF capacitors are highly desired for the miniaturization of RFIC chips. However, practical and simple solutions are limited by existing capabilities in three dimensional (3D) structure construction and the effective configuration of electrodes. We report a unique route to achieve unprecedentedly high capacitance density at a high operating frequency through a capacitor configuration of 3D coil interdigital electrodes using planar semiconductor processing compatible materials and fabrication methods. A systematic mechanical electrical design principle is demonstrated, and fabricated devices show a maximum 21.5 pF capacitance, which is 17.2x larger after rolling up. The corresponding capacitance density is as large as 371 pF mm 2, with resonant frequency of 1.5 GHz. The performance could be improved significantly by simply rolling up more turns with minimal change to the area footprint.
author_names: Lei Sang

Hao Zhou

Zhendong Yang

Mark Kraman

Hao Zhao

Julian A Michaels

Dane J Sievers

Jose E Schutt-Aine

Xiuling Li

Wen Huang
title: Monolithic radio frequency SiN x self rolled up nanomembrane interdigital capacitor modeling and fabrication.
venue: Nanotechnology
year: 2019

abstract: The investigation of charge transport in organic nanocrystals is essential to understand nanoscale physical properties of organic systems and the development of novel organic nanodevices. In this work, we fabricate organic nanocrystal diodes contacted by rolled up robust nanomembranes. The organic nanocrystals consist of vanadyl phthalocyanine and copper hexadecafluorophthalocyanine heterojunctions. The temperature dependent charge transport through organic nanocrystals was investigated to reveal the transport properties of ohmic and space charge limited current under different conditions, for instance, temperature and bias.
author_names: Vineeth Kumar Bandari

Lakshmi Varadharajan

Longqian Xu

Abdur Rehman Jalil

Mirunalini Devarajulu

Pablo F Siles

Feng Zhu

Oliver G Schmidt
title: Charge transport in organic nanocrystal diodes based on rolled up robust nanomembrane contacts
venue: Beilstein journal of nanotechnology
year: 2017

abstract: Multilayer vanadium dioxide (VO2) actuators are a widespread concern as these micro/nano actuators present a fast and efficient dynamic response when VO2 occurs in metal insulator transition (MIT) at 68 degC. By tuning the O2 flow rate during oxide deposition and rolled up nanotechnology, a microactuator based on a single layered vanadium oxide nanomembrane with vertical component gradient is fabricated. Upward bending of the nanomembrane is driven by the release of the compressive strain gradient which is revealed through the difference in Raman shift of the vibration mode. Combining strain engineering, the initial curvature of microactuators is tuned in a wide range by the thickness of the nanomembranes. The actuation behavior from low curvature to high final curvature across the MIT is observed which depends on the nanomembrane thickness. Initial compressive strain distribution of the rolled up nanomembrane decreases the MIT temperature simultaneously. Thus, taking advantage of the tunable MIT and reversible shape transformation, micro/nano actuators with tunable triggering temperature, controllable initial curvature and large displacement actuation are fabricated for curvature engineering in micromechanical systems.
author_names: Xing Li

Borui Xu

Xuefei Zhou

Chuanling Men

Ziao Tian

Yongfeng Mei
title: Rolled up single layered vanadium oxide nanomembranes for microactuators with tunable active temperature.
venue: Nanotechnology
year: 2019

abstract: Pyrolysis, which involves thermal decomposition of materials at elevated temperatures, has been commonly applied in the chemical industry. Here we explored the pyrolysis process for 3D nanofabrication. By strain engineering of nanomembranes on a thermal responsive polymer as the sacrificial layer, we demonstrated that diverse 3D rolled up microstructures with different functions could be achieved without any additional solution and drying process. We carefully studied the effect of molecular weight of the polymer in the pyrolysis process and identified that the rapid breakdown of molecular backbone to a monomer is the key for nanomembrane releasing and rolling. Preferential rolling direction and corresponding dynamics were studied by analyzing the real time video of the rolling process. We further demonstrated the versatile functions of the fabricated 3D structures as catalytic microengines and optical resonators. The simple fabrication methodology developed here may have great potential in producing functional 3D tubular micro /nanostructures.
author_names: Fei Ma

Borui Xu

Shuai Wu

Lu Wang

Biran Zhang

Gaoshan Huang

Ai Du

Bin Zhou

Yongfeng Mei
title: Thermal controlled releasing and assembling of functional nanomembranes through polymer pyrolysis.
venue: Nanotechnology
year: 2019

abstract: We employ glass microtube structures fabricated by rolled up nanotechnology to infer the influence of scaffold dimensionality and cell confinement on neural stem cell (NSC) migration. Thereby, we observe a pronounced morphology change that marks a reversible mesenchymal to amoeboid migration mode transition. Space restrictions preset by the diameter of nanomembrane topography modify the cell shape toward characteristics found in living tissue. We demonstrate the importance of substrate dimensionality for the migration mode of NSCs and thereby define rolled up nanomembranes as the ultimate tool for single cell migration studies.
author_names: Britta Koch

Anne K Meyer

Linda Helbig

Stefan M Harazim

Alexander Storch

Samuel Sanchez

Oliver G Schmidt
title: Dimensionality of Rolled up Nanomembranes Controls Neural Stem Cell Migration Mechanism
venue: Nano letters
year: 2015

abstract: Energy storage devices, acting as complementing units for renewable energy sources, play a key role in modern society, and they serve as the dominant power supply for most portable electronics. At the heart of the development of next generation energy storage devices lies the exploration of intrinsic material properties, architectural design and fabrication methods. Rolled up nanotechnology, a unique method to self assemble nanomembranes into 3D structures using strain engineering, has advanced the development of energy storage devices with superior performance. In this review, the recent progress of employing rolled up nanotechnology is focused to design rational electrodes for Li ion (LIBs) and Li O2 batteries. A comprehensive summary of the fabrication and application of diverse rolled up structures in these electrochemical energy storage devices is provided. Apart from this, the great potential of this approach is also highlighted for scalable miniaturized microdevice fabrication, including micro LIBs, microsupercapacitors, and microscale ultracompact capacitors. These devices offer a promising platform not only for electrochemical microprobes, but also for lab on a chip applications. Finally, prospects and challenges of employing rolled up nanotechnology for future research and development in the broad field of energy storage systems are discussed.
author_names: Junwen Deng

Xueyi Lu

Lixiang Liu

L Zhang

Oliver G Schmidt
title: Introducing Rolled Up Nanotechnology for Advanced Energy Storage Devices
year: 2016

abstract: Abstract Rolled up nanotechnology involves the deposition of strained material layers for subsequent release and relaxation into functional structures with applications spanning several disciplines. Originally developed for use with semiconductor materials, over the last decade the processes involved in rolled up nanotechnology have been applied across a wide palette of materials resulting in applications (among others) in micro robotics, energy storage, electronics, and photonics. Here we highlight the key advancements and future directions in rolled up photonics, focusing on the diverse demonstrations of rolled up three dimensional microresonators which enable integrated sensing, micro lasing, and out of plane routing of light.
author_names: Stefan Bottner

Matthew R Jorgensen

Oliver G Schmidt
title: Rolled up nanotechnology: 3D photonic materials by design
year: 2016

abstract: Artificial microvasculature, particularly as part of the blood brain barrier, has a high benefit for pharmacological drug discovery and uptake regulation. We demonstrate the fabrication of tubular structures with patterns of holes, which are capable of mimicking microvasculatures. By using photolithography, the dimensions of the cylindrical scaffolds can be precisely tuned as well as the alignment and size of holes. Overlapping holes can be tailored to create diverse three dimensional configurations, for example, periodic nanoscaled apertures. The porous tubes, which can be made from diverse materials for differential functionalization, are biocompatible and can be modified to be biodegradable in the culture medium. As a proof of concept, endothelial cells (ECs) as well as astrocytes were cultured on these scaffolds. They form monolayers along the scaffolds, are guided by the array of holes and express tight junctions. Nanoscaled filaments of cells on these scaffolds were visualized by scanning electron microscopy (SEM) This work provides the basic concept mainly for an in vitro model of microvasculature which could also be possibly implanted in vivo due to its biodegradability.
author_names: Rerngchai Arayanarakool

Anne K Meyer

Linda Helbig

Samuel Sanchez

Oliver G Schmidt
title: Tailoring three dimensional architectures by rolled up nanotechnology for mimicking microvasculatures.
venue: Lab on a chip
year: 2015

abstract: Two types of on chip RFIC transformers based on CMOS compatible strain induced self rolled up membrane (S RuM) nanotechnology, with extremely small footprint, are demonstrated. The rolled up transformers, with their 3D tubular form factors, dramatically reduce the substrate parasitic effects and push the maximum working frequency into millimeter wave bands with a coupling coefficient, k, as high as 0.92. The 3D stand up nature also allows the tube transformers to be less susceptible to residue stress in the substrate and thus compatible with flexible platforms for wearable RF applications. The demonstrated samples with a turn ratio, n, of 5.5:1 only occupies 805 mm2 on chip area (s) which is 12x smaller than that of the best planar transformer with the same turn ratio, and its figure of merit n*k/s, is therefore 6046/mm2, enhanced by 15x.Copyright (c) 2015 by ASME
author_names: Wen Huang

Moyang Li

Songbin Gong

Xiuling Li
title: RFIC Transformer With 12x Size Reduction and 15x Performance Enhancement by Self Rolled Up Membrane Nanotechnology
year: 2015

abstract: Germanium Tin (GeSn) alloys have attracted great amounts of attention as these group IV semiconductors present direct band gap behavior with high Sn content and are compatible with current complementary metal oxide semiconductor technology. In this work, three dimensional tubular GeSn/Ge micro resonators with a diameter of around 7.3 mm were demonstrated by rolling up GeSn nanomembranes (NM) grown on a Ge on insulator wafer via molecular beam epitaxy. The microstructural properties of the resonators were carefully investigated and the strain distributions of the rolled up GeSn/Ge microcavities along the radial direction were studied by utilizing micro Raman spectroscopy with different excitation laser wavelengths. The values of the strains calculated from Raman shifts agree well with the theoretical prediction. Coupled with fiber tapers, as fabricated devices present a high quality factor of up to 800 in the transmission spectral measurements. The micro resonators fabricated via rolled up nanotechnology and GeSn/Ge NMs in this work may have great potential in photonic micro and nanodevices.
author_names: Xiang Wu

Ziao Tian

Hui Cong

Yang Wang

Riyanto Edy

Gaoshan Huang

Zengfeng Di

Chunlai Xue

Yongfeng Mei
title: Infrared tubular microcavity based on rolled up GeSn/Ge nanomembranes.
venue: Nanotechnology
year: 2018