Carbon Nanotube Thin Films: Fabrication, Properties, and Applications

Printed electronics represent an emerging area of research that promises large markets due to the ability to bypass traditional expensive and inflexible silicon-based electronics to fabricate a variety of devices on flexible substrates using high-throughput printing approaches. This article presents a summary of work to date in the field of printed electronics and the materials chemistry involved. In particular, the focus is upon the use of metal- and metal oxide-containing inks in the preparation of contacts and interconnects. The review discusses the challenges associated with processing these types of inks and ways to successfully obtain the desired features.

Printed electronics: the challenges involved in printing devices, interconnects, and contacts based on inorganic materials

The catalyst in the CCVD of carbon nanotubes—a review

Li-ion batteries have been employed successfully in various small electronic devices for the last two decades, and the types of applications are currently expanding to include electric vehicles (EVs), power tools, and large electric power storage units. In order to be implemented in these emerging markets, novel materials for negative and positive electrodes as well as electrolytes need to be developed to achieve high energy density, high power, and safe lithium rechargeable batteries. Here, the trends of the market and development of materials for each application are introduced, and some of next generation Li-ion batteries are discussed.

Prospective materials and applications for Li secondary batteries

The invention provides methods and devices for fabricating printable semiconductor elements and assembling printable semiconductor elements onto substrate surfaces. Methods, devices and device components of the present invention are capable of generating a wide range of flexible electronic and optoelectronic devices and arrays of devices on substrates comprising polymeric materials. The present invention also provides stretchable semiconductor structures and stretchable electronic devices capable of good performance in stretched configurations.

Methods and devices for fabricating and assembling printable semiconductor elements

A novel super ink jet printing (SIJP) system was used to fabricate 3D zinc–silver microbatteries directly on a substrate. The SIJP provides a simple and flexible method to deposit interesting 2D and 3D structures of varying morphologies without the waste and large energy inputs typical of standard microfabrication technologies. The system was used to print pairs of silver electrodes with arrays of pillars on glass substrates, and in the presence of an electrolyte, the battery self-assembled during the first charge. Using an aqueous electrolyte solution of KOH with dissolved ZnO, the SIJP printed structures showed similar electrochemical behavior to batteries composed of silver foil electrodes. For a sparse array of pillars (~2.5% footprint area of each electrode pad occupied by pillars), a capacity increase of 60% was achieved in comparison with a cell with planar electrodes.

https://iopscience.iop.org/article/10.1088/0960-1317/19/9/094013/pdf

A super ink jet printed zinc–silver 3D microbattery

We have developed an ink-jet system which allows arrangements of dots with a submicron minimum size. Using an ultra-fine silver paste, we achieved the direct print of metallic wires of only a few micrometers in width without any pre-patterning treatment of the substrate, hydrophobic/hydrophilic patterning, bank patterning etc. We also propose an application, such as direct printing of ultra-fine redistribution wiring for a build-up board and/or package. Since all of these processes can be carried out at atmospheric pressure on the desktop without special treatment of the substrate. The direct fabrication process using ink-jet printing can be expected to be a powerful tool for both nanotechnology research and applications such as micro electronics, etc.

Super-fine ink-jet printing: toward the minimal manufacturing system

The super-fine inkjet system which allows arrangements of dots with a minimum size of less than one micron has been developed. Using an ultra-fine silver paste, we achieved the direct print of ultra-fine metallic wire of only a few micrometers in width without any pre-patterning treatment on substrate. We also propose an application, such as, direct printing of ultra-fine redistribution wiring for build-up board and/or package. Since, all these process can be carried out at atmospheric pressure on the desktop without special treatment on the substrate, such as hydrophobic/ hydrophilic-patteming, bank patterning etc. As shown in this paper, the direct fabrication process using ink-jet printing are expected to be a powerful tool for both nanotechnology research and practical use such as micro electronics etc.

Super-fine inkjet printing - : toward the minimal manufacturing system

We report on site-selective growth of multiwalled carbon nanotubes (MWNTs) from a Co nanoparticle catalyst patterned by an ink-jet printing (IJP) technique. The dispersion of the Co nanoparticles was employed as “catalyst ink” for the IJP, and the catalyst pattern was subjected to chemical vapor deposition of acetylene gas. The patterned array of MWNTs was obtained with a dot size around 5–30 μm and showed field emission of electrons corresponding to the printed pattern. The present method offers a simple and powerful means to pattern carbon nanotubes at desired positions with any patterns.

Ink-jet printing of nanoparticle catalyst for site-selective carbon nanotube growth

An ultrafine fluid jet apparatus including a substrate arranged near a distal end of an ultrafine-diameter nozzle to which a solution is supplied, and an optional-waveform voltage is applied to the solution in the nozzle to eject an ultrafine-diameter fluid droplet onto a surface of the substrate; wherein an electric field intensity near the distal end of the nozzle according to a diameter reduction of the nozzle is sufficiently larger than an electric field acting between the nozzle and the substrate; and wherein Maxwell stress and an electro-wetting effect being utilized, a conductance is decreased by a reduction in the nozzle diameter or the like, and controllability of an ejection rate by a voltage is improved; and wherein landing accuracy is exponentially improved by moderation of evaporation by a charged droplet and acceleration of the droplet by an electric field.

Kazuhiro Murata

Papers

A super ink jet printed zinc–silver 3D microbattery

Super-fine ink-jet printing: toward the minimal manufacturing system

Super-fine inkjet printing - : toward the minimal manufacturing system

Ink-jet printing of nanoparticle catalyst for site-selective carbon nanotube growth

Ultrafine fluid jet apparatus