Name: Planar and Three-Dimensional Printing of Conductive Inks (Video) | JoVE Journal
Uploaded: 2011-12-09T12:00:00.000+00:00
Duration: 10 min 49 s
Description: Learn direct right assembly for printing conductive microelectrodes using silver nanoparticle inks. This method enables fabrication of complex 3D structures for electronic and biomedical device applications.

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5 minutes

This material is based on work supported by the U.S. Department of Energy, Materials Sciences and Engineering Division (Award No. DEFG-02-07ER46471) and the DOE Energy Research Center on Light-Materials Interactions in Energy Conversion (Award No. DE-SC0001293), and benefitted from access to the Center for Microanalysis of Materials within the Frederick Seitz Materials Research Laboratory (FSMRL).

1. Introduction
<ol>
	<li>This paper demonstrates the 1D, 2D, and 3D printing of conductive microelectrodes via direct-write assembly.</li>
	<li>Direct-write assembly is a method of building up 1D-to-3D printed structures by the deposition of concentrated inks through fine nozzles.</li>
	<li>Our system consists of a computer-controlled 3-axis translation stage, an ink reservoir and nozzle, and 10x telescopic lens for imaging (Figure 1).</li>
	<li>Direct-write assembly is a filamentary printing approach in which concentrated inks are extruded through cylindrical nozzles, whose diameters range from 0.1 to 250 μm (Figure 2). Notably, due to the viscoelastic ink characteristics, direct-write assembly enables self-supporting spanning features (Figure 3). To date, a wide range of inks, including those composed of ceramic6,7, organic8-10, metallic11-15, polymeric16,17, and sol-gel18,19 materials have been developed for this printing approach (Figure 4).</li>
</ol>
2. Preparation of highly concentrated silver nanoparticle inks
<ol>
	<li>Silver nanoparticle inks are prepared by first dissolving a blend of 5,000 and 50,000 molecular weight of poly(acrylic acid) in a mixture of 50 g water and 40 g diethanolamine (Video 2.1).</li>
	<li>The polymer acts as a capping agent to control the size of the silver nanoparticles.</li>
	<li>Next, an aqueous solution of silver nitrate is injected into the polymer solution. After addition, a light yellow transparent solution is obtained (Video 2.2).</li>
	<li>After stirring for 24 hrs at room temperature, the solution develops a reddish-brown color (Video 2.3), that coincides with the formation of silver nanoparticles of 5 nm diameter, as determined by transmission electron microscopy.</li>
	<li>Next, the solution is sonicated at 65 °C in a water bath for 2 hrs for further particle growth (Video 2.4).</li>
	<li>After sonication, the solution is transferred to a 500 ml beaker and cooled to room temperature. Then, 300 ml of ethanol is titrated at a rate of 30 ml / min. Since ethanol is a poor solvent for the poly(acrylic acid) capping agent, the particles rapidly coagulate and precipitate from solution (Video 2.5).</li>
	<li>After decanting the supernatant, the precipitate is collected into a centrifuge tube and centrifuged at 9000 rpm for 20 minutes (Video 2.6).</li>
	<li>After this step, a highly concentrated silver nanoparticle ink with a solids loading of ~85 wt% is obtained (Video 2.7).</li>
	<li>Further control over ink viscosity and elastic modulus can be achieved by dilution, followed by homogenization. For an example, a humectant solution, such as ethylene glycol, can be added to the ink and then homogenized at 2000 rpm for 3 minutes using a Thinky homogenization mixer. After this process, a uniform ink of a bluish to magenta color is obtained (Video 2.8).</li>
	<li>The TEM image shows silver nanoparticles obtained by this synthesis procedure (Figure 5_left). The particles have a mean diameter of 20 nm with a size distribution of 5-50 nm. Printed structures require post-annealing to enhance their conductivity. After annealing at 250°C for less than 30 min, the silver nanoparticles form conductive microelectrodes with an electrical resistivity approaching to 10-5 Ω•cm (Figure 5_bottom right). The microstructural evolution of the printed silver microelectrodes as a function of annealing temperature is shown in Figure 5_top right. As the temperature increases from 150° to 550°C, the microelectrodes undergo densification with a total volumetric shrinkage of ~30%.11</li>
	<li>The ink rheology, which strongly depends on its solids loading, determines its printability. The ink viscosity increases with increasing solids loading (Figure 6). Because dilute inks with low viscosity result in a significant lateral spreading, concentrated inks with a solids loading ranging from 70 to 85 wt% are required for printing of planar and spanning ink filaments.</li>
	<li>The ink elastic modulus increases with increasing solids loading (Figure 7). In the linear viscoelastic region, the elastic modulus rises nearly three orders of magnitude as the solids loading increases 60 to 75 wt%. A minimum elastic modulus of 2000 Pa is required to produce self-supporting or spanning features.</li>
</ol>
3. Direct-write assembly
<ol>
	<li>Direct-write assembly is carried out by first loading the ink into a syringe barrel. After attaching a deposition nozzle, the ink-loaded syringe barrel is mounted onto the 3-axis printing stage (Video 3.1).</li>
	<li>Using a computer program, arbitrary designs, including linear, planar, and complex three-dimensional structures can be easily generated (Video 3.2).</li>
	<li>Next, the nozzle height is adjusted with the aid of telescope lens with a 10x zoom (Video 3.3).</li>
	<li>After applying pressure using an air-powered fluid dispensing system, the ink is deposited onto the substrate with a controlled printing speed (Video 3.4). The required pressure depends upon ink rheology, nozzle diameter, and printing speed, but typical values range from 10-100 psi at 20-500 μm/s. This printing is performed in air at room temperature. Using this printing procedure, the printing of silver microelectrodes in different layouts and size scales is demonstrated.</li>
	<li>For an example, the printing of conductive silver grids with a center-to-center line spacing of 100 μm, patterned by a 5-μm nozzle on a silicon wafer substrate is demonstrated (Video 3.5).</li>
	<li>In addition, this video shows how to create a high aspect ratio cylindrical structure by a 30-μm nozzle using a layer-by-layer printing method (Video 3.6).</li>
	<li>Furthermore, the omnidirectional printing of silver microelectrodes between two glass substrates offset by a 1-mm height difference is demonstrated using a 30-μm nozzle (Video 3.7).</li>
	<li>Completely free-standing, vertically printed silver microspikes can be created by a 30-μm nozzle on a Si wafer substrate (Video 3.8).</li>
	<li>Finally, this video shows direct writing of a spanning silver microelectrode using a 10-μm nozzle (Video 3.9). The printed feature can span distances up to one centimeter with minimal drooping or buckling.</li>
</ol>
4. Representative results:
We prepared a highly concentrated silver nanoparticle inks and demonstrated printed conductive features in planar and 3D motifs for electronic and optoelectronic applications with printing resolution ~ 2 - 30 μm. For an example, Figure 8 exhibits the printing resolution of this technique. Printed features with minimum electrode width of ~ 2 μm (1.4 μm thick) are obtained in a single pass using a 1-μm nozzle11.
Figure 9 shows transparent conductive silver grids, patterned by a 5 μm nozzle on a flexible polyimide film12. The texts underneath the printed grids are clearly visible. These transparent silver grids could be attractive alternatives for transparent conducting oxide (TCO) materials.
Conformal printing onto a non-planar substrates is also enabled by this method. Figure 10 demonstrates the conformal printing of a 3D electrically small antenna. A 100 μm metal nozzle is used to print meander-line patterns on the surface of a glass hemisphere13. This approach may find several applications including implantable and wearable antennas, electronics, and sensors.
Applications of spanning silver microelectrodes in three-dimensional photovoltaics and light-emitting diodes are demonstrated (Figure 11-14).
First, Figure 11 is an example of silicon spherical shell. This tenuous film with a 2-μm thickness can be wire-bonded to an external circuit by omnidirectional printing14. This method uses minimal contact pressure, which is highly advantageous for delicate devices.
Next, Figure 12 demonstrates an example of printing a spanning interconnect for a silicon solar microcell array in which silicon microribbon elements are separated by 33-μm gap15.
Next, Figure 13 shows silver interconnects for the gallium arsenide-based LED array with 4-by-4 pixels, where each pixel (500 x 500 x 2.5 μm3) is spaced 200 μm apart11. The bottom image displays the LED array, emitting uniform red light under an applied bias of 6 V from a single pixel. The ability to print spanning electrodes enables multilayer interconnection without the use of supporting or sacrificial layers (top images).
As a final demonstration, Figure 14 shows SEM images for the complex 3D microperiodic silver lattice printed by a 5μm nozzle.
<img alt="Optical microscopy setup, 3-axis motion stage, air supply for precision material analysis." src="/files/ftp_upload/3189/3189fig1.jpg" data-altupdatedat="1754907495000" data-alt="Figure 1"> 
Figure 1. Optical image of direct ink writing apparatus.
<img alt="3D printing process diagram; nozzle extruding filament for layered manufacturing analysis." src="/files/ftp_upload/3189/3189fig2.jpg" data-altupdatedat="1754907495000" data-alt="Figure 2"> 
Figure 2. Direct ink writing of a filamentary feature.
<img alt="3D printing process diagram with nozzle, spanning features, air, ink, indicating additive manufacturing." src="/files/ftp_upload/3189/3189fig3.jpg" data-altupdatedat="1754907495000" data-alt="Figure 3"> 
Figure 3. Direct ink writing of self-supporting spanning features.
<img alt="Ceramic, organic, metal, polymer, sol-gel inks; feature size comparison; microscopy, 3D printing." src="/files/ftp_upload/3189/3189fig4.jpg" data-altupdatedat="1754907495000" data-alt="Figure 4"> 
Figure 4. Ink designs for direct ink writing. A wide range of concentrated viscoelastic inks have been developed for direct writing of planar and complex 3D structures with microscale features.
<img alt="Nanoparticle microstructure TEM, annealing impact graph, resistivity vs. time, thermal analysis." src="/files/ftp_upload/3189/3189fig5.jpg" data-altupdatedat="1754907495000" data-alt="Figure 5"> 
Figure 5. (Left) Transmission electron microscopy (TEM) image of silver nanoparticles. (Top right) SEM images of silver microelectrodes patterned with a 15-μm nozzle as a function of annealing temperature. (Bottom right) Electrical resistivity of silver microelectrodes as a function of annealing temperature and time.
<img alt="Graph of ink viscosity vs. silver content showing 3D printing parameters and lateral spreading." src="/files/ftp_upload/3189/3189fig6.jpg" data-altupdatedat="1754907495000" data-alt="Figure 6"> 
Figure 6. Apparent viscosity (η) of the silver nanoparticle inks as a function of solids loading.
<img alt="Elastic modulus vs. shear stress graph; material wt% analysis; rheological properties study." src="/files/ftp_upload/3189/3189fig7.jpg" data-altupdatedat="1754907495000" data-alt="Figure 7"> 
Figure 7. Shear elastic modulus (G') as a function of shear stress for silver nanoparticle inks of varying solids loading.
<img alt="SEM image of nanoscale grating pattern; surface morphology, material analysis, 50 µm scale bar." src="/files/ftp_upload/3189/3189fig8.jpg" data-altupdatedat="1754907495000" data-alt="Figure 8"> 
Figure 8. SEM images of planar arrays of silver microelectrodes patterned on a Si wafer with a 1-μm nozzle.
<img alt="Flexible electronic circuit, microscopy image, grid scale showing microstructure, 3mm and 400μm scales." src="/files/ftp_upload/3189/3189fig9.jpg" data-altupdatedat="1754907495000" data-alt="Figure 9"> 
Figure 9. Optical image of transparent conductive silver grids (left) and SEM images of the grids printed as a function of line pitch (right).
<img alt="3D printing process; diagram of nozzle with printed silver meanderlines; conductive ink deposition. " src="/files/ftp_upload/3189/3189fig10.jpg" data-altupdatedat="1754907495000" data-alt="Figure 10"> 
Figure 10. Optical image captured during conformal printing of electrically small antennas on a hemispherical glass substrate.
<img alt="Spanning Ag microelectrode with nozzle in nanofabrication setup; microscopy image; scale 100μm." src="/files/ftp_upload/3189/3189fig11.jpg" data-altupdatedat="1754907495000" data-alt="Figure 11"> 
Figure 11. Optical image obtained during printing of spanning silver microelectrodes onto a thin (2-μm) silicon spherical shell.
<img alt="SEM diagram of Si solar micro-cells with spanning Ag microelectrode, scale 25 μm." src="/files/ftp_upload/3189/3189fig12.jpg" data-altupdatedat="1754907495000" data-alt="Figure 12"> 
Figure 12. SEM image of a spanning silver microelectrode printed onto a silicon solar microcell array.
<img alt="Micro-LED emission, silver microelectrode interconnects; optical excitation, microscopy image." src="/files/ftp_upload/3189/3189fig13.jpg" data-altupdatedat="1754907495000" data-alt="Figure 13"> 
Figure 13. SEM images (top) and optical image (bottom) of a 4-by-4 LED chip array interconnected by silver microelectrodes.
<img alt="SEM micrograph of 3D printed micro-lattice structure; magnified inset shows detailed fiber arrangement." src="/files/ftp_upload/3189/3189fig14.jpg" data-altupdatedat="1754907495000" data-alt="Figure 14"> 
Figure 14. SEM image of 3D microperiodic silver lattice.

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No conflicts of interest declared.

Conventional droplet-based printing approaches, such as inkjet printing, are limited to the fabrication of planar electrodes with low aspect ratio due to the dilute nature and low viscosity of the inks used. Recently, dip-pen nanolithography (DPN)20-22 and e-jet printing23-25 have been used to pattern conductive features. These routes also employ dilute, low viscosity inks. Pearton and co-workers used DPN to deposit a commercially available silver nanoparticle ink at write speeds of up to 1600 &mu;m s-1 and line widths of approximately 0.5 &mu;m22. However, fabrication of reproducible patterns over large areas has yet to be demonstrated by this approach. Silver nanoparticle inks have also been deposited by e-jet printing to form conductive traces with line widths of ~ 1.5 &mu;m25. However, as with inkjet printing, inhomogeneous printed features may arise due to satellite drop formation and non-uniform drop drying24,25.
As demonstrated above, direct-write assembly of concentrated silver nanoparticle inks overcomes these limitations through a filamentary-based printing approach. This technique enables the fabrication of conductive microelectrodes with a high aspect ratios (h/w &asymp; 1.0) in a single passes allowing the creation of 1D, 2D, and 3D architectures. The size of the printed features depends upon nozzle diameter, ink solids loading, applied pressure, and printing speed. To date, conductive traces as small as ~ 2 &mu;m have been patterned using a 1 &mu;m nozzle at modest speeds (&lt; 2 mm s-1). By tailoring the ink composition and nozzle geometry, maximum printing speeds in excess of 10 cm s-1 are possible. However, high speed printing of using fine nozzles (&lt; 5 &mu;m) remains a significant challenge.
To demonstrate applications of direct-write assembly, we fabricated conductive grids, electrically small antennas, solar cells, and light-emitting diodes with planar and spanning printed electrodes (Figure 8-14). Notably, our approach is not restricted to the creation of metallic structures. Using other ink designs, such as those based on silk fibroin, hydrogel and fugitive organic inks, we have constructed 3D scaffolds and microvascular networks for tissue engineering and cell culture via direct-write assembly26-30.
Looking towards the future, there are many opportunities and challenges. Further advances require new ink designs, better modeling of ink flow dynamics, and enhanced robotic and control systems. Large-area fabrication of 1D to 3D structures with high throughput and nanoscale resolution (&lt; 100 nm) remains a significant challenge.

<table><tbody><tr><td>Poly(acrylic acid)</td><td>Polysciences, Inc.</td><td>06519</td><td>m.w. 5,000 g/mol</td></tr><tr><td>Poly(acrylic acid)</td><td>Polysciences, Inc.</td><td>00627</td><td>m.w. 50,000 g/mol</td></tr><tr><td>Silver nitrate</td><td>Sigma-Aldrich</td><td>209139</td><td>Silver source</td></tr><tr><td>Diethanolamine</td><td>Sigma-Aldrich</td><td>D8885</td><td>Solvent/Reducing agent</td></tr><tr><td>Ethylene glycol</td><td>Sigma-Aldrich</td><td>102466</td><td>Humectant</td></tr><tr><td>Sonicater</td><td>Fisher Scientific</td><td>FS30H</td><td>-</td></tr><tr><td>Centrifuge</td><td>Beckman Coulter Inc.</td><td>Avanti&lt;sup&gt;TM&lt;/sup&gt; J-25 I</td><td>-</td></tr><tr><td>Robotic stage</td><td>Aerotech Inc.</td><td>ABL 900010</td><td>3-axis motion</td></tr><tr><td>Syringe barrel</td><td>EFD Inc.</td><td>5109LBP-B</td><td>3 ml</td></tr><tr><td>Nozzle</td><td>EFD Inc.</td><td>-</td><td>i.d. = 0.1 - 250 &amp;#x03BC;m</td></tr><tr><td>Dispenser</td><td>EFD Inc.</td><td>800</td><td>Air-powered</td></tr><tr><td>Design software</td><td>Custom Made</td><td>-</td><td>Mingjie Xu</td></tr></tbody></table>

planar and three-dimensional printing of conductive inks

Planar and Three-Dimensional Printing of Conductive Inks

Printed electronics rely on low-cost, large-area fabrication routes to create flexible or multidimensional electronic, optoelectronic, and biomedical devices1-3. In this paper, we focus on one- (1D), two- (2D), and three-dimensional (3D) printing of conductive metallic inks in the form of flexible, stretchable, and spanning microelectrodes.
Direct-write assembly4,5 is a 1-to-3D printing technique that enables the fabrication of features ranging from simple lines to complex structures by the deposition of concentrated inks through fine nozzles (~0.1 - 250 &mu;m). This printing method consists of a computer-controlled 3-axis translation stage, an ink reservoir and nozzle, and 10x telescopic lens for visualization. Unlike inkjet printing, a droplet-based process, direct-write assembly involves the extrusion of ink filaments either in- or out-of-plane. The printed filaments typically conform to the nozzle size. Hence, microscale features (&lt; 1 &mu;m) can be patterned and assembled into larger arrays and multidimensional architectures.
In this paper, we first synthesize a highly concentrated silver nanoparticle ink for planar and 3D printing via direct-write assembly. Next, a standard protocol for printing microelectrodes in multidimensional motifs is demonstrated. Finally, applications of printed microelectrodes for electrically small antennas, solar cells, and light-emitting diodes are highlighted.

Planar and three-dimensional printing of conductive metallic inks is described. Our approach provides new avenues for fabricating printed electronic, optoelectronic, and biomedical devices in unusual layouts at the microscale.

Printed electronics rely on low-cost, large-area fabrication routes to create flexible or multidimensional electronic, optoelectronic, and biomedical ...

The aim of this experiment is to demonstrate the planar and three dimensional printing of conductive micro electrodes via direct right assembly. Direct right assembly is a deposition technique, which is composed of a computer controlled three axis translation stage, ink, nozzle, and air supply. In this printing method, highly concentrated inks are extruded through a fine cylindrical nozzle whose diameters range from 0.1 to 250 microns due to the viscoelastic ink characteristics.Direct right assembly enables self-supporting spanning features. To date, a wide range of inks, including those composed of ceramic, organic metal polymer, and soul gel materials have been developed for this printing approach. The main advantage of this technique of the existing vessel, such as is a direct wide assembly of complex release structure, is faster that using, Although this method provides insight into conductive inks for electronic and optical electronic applications, it can also be applied to other material systems that could be used for biomedical scaffolds and sensors.Visualizing this procedure is critical because the ink radiology and printing expertise strongly influenced the quality of the printed structures demonstrating this procedure is bhan a postdoc and Annalisa Russo, a PhD student from my laboratory, Silver nanoparticle inks, are prepared by first dissolving a blend of 5, 000 and 50, 000 molecular weight acrylic acid in a mixture of water and di ethanol amine. The polymer acts as a capping agent to control the size of the silver nanoparticles. Next, inject an aqueous silver nitrate solution into the polymer solution.The mixture will become a transparent light yellow, continue stirring for 24 hours at room temperature. After stirring, the solution develops a reddish brown color. This is due to formation of five nanometer diameter silver nanoparticles, which can be confirmed using TEM to further particle growth.Sonicate the solution in a 65 degree Celsius water bath for two hours after sonication transfer the solution to a 500 milliliter beaker to call it to room temperature, once called titrate 300 milliliters of ethanol into the solution. Because ethanol is a poor solvent for the capping agents, the particles rapidly coagulate and precipitate now decant the supena and collect the precipitate in a centrifuge tube. Centrifuge the precipitate at 9, 000 RPM for 20 minutes.The result will be a highly concentrated silver nanoparticle ink with about 85%solids by weight. For further control over ink viscosity and elastic modulus dilute the ink into a humectant solution such as ethylene glycol, then homogenize the solution at 2000 RPM for three minutes using a thinky homogenization mixer. This dilution and homogenization process makes a uniform bluish to magenta ink.The TEM image shows silver nanoparticles obtained by this synthesis procedure. The particles have a mean diameter of 20 nanometers with a size distribution of five to 15 nanometers. Printed structures require poster kneeling to enhance their conductivity.After an kneeling at 250 degrees Celsius for less than 30 minutes, the silver nanoparticles form conductive micro electrodes with an electrical resistivity approaching 10 to the minus five ohm centimeters. The micro structural evolution of the printed silver micro electrodes as a function of a kneeling temperature is measured by SEM. As the temperature increases from 150 degrees to 550 degrees Celsius, the micro electrodes undergo densification with a total volumetric shrinkage of about 30%The ink ology, which strongly depends on its solid loading, determines its printability.The ink viscosity increases with increasing solid loading because diluting with low viscosity result in a significant lateral spreading concentrated inks. With the solids loading ranging from 70 to 85, weight percent are required for printing of planar and spanning ink filaments. The ink elastic modulus increases with increasing solids loading in the linear viscoelastic region.The elastic modulus rises nearly three orders of magnitude. As the solids loading increases 60 to 75 weight percent. A minimum elastic modulus of 2000 pascals is required to produce self-supporting or spanning features.To begin direct right assembly, load the ink into a syringe barrel. After attaching a deposition, nozzle mount the ink loaded syringe barrel to the three axis printing stage. Use a computer program to generate the design of interest, which could be a linear planar or complex three dimensional structure.Next, the nossel height is adjusted with the aid of a telescope lens with a 10 times zoom. After applying pressure with an air powered fluid dispensing system, deposit the ink onto the substrate at room temperature using a controlled print in speed and pressure. These variables depend on the ink, radiology, nozzle, diameter, and printing speed.A five micron nozzle can print conductive silver grids with a center to center line spacing of 100 microns on a silicon wafer substrate. Using a 30 micron nozzle and layer by layer printing can make a high aspect ratio Cylindrical structure. Omnidirectional printing of silver micro electrodes between two glass substrates is possible using a 30 micron nozzle.The glass substrates are offset by one millimeter complete freestanding vertically printed silver micro spikes can be created using a 30 micron nozzle on a silicone wafer substrate. Direct writing of a spanning silver micro electrodes using a 10 micron nozzle is also possible. The printed feature can span distances up to one centimeter with minimal drooping or buckling.Highly concentrated silver nanoparticle ink was printed as conductive features in planar and 3D motifs for electronic and optoelectronic applications. The printing resolution was between two and 30 microns. A minimum electrode width of about two microns and a thickness of 1.4 microns was obtained in a single pass using a one micron nozzle, a five micron nozzle pattern.Transparent conductive silver grids on a flexible polyamide film. The text underneath the grid remained clearly visible. These metallic grids may serve as high conductivity alternatives to transparent conductive oxide materials.Conformal printing of a 3D electrically small antenna was possible with a 100 micron metal nozzle meander. Line patterns were printed on the surface of a glass hemisphere. This approach may find several applications, including implantable and wearable antennas, electronics and sensors, applications of spanning silver micro electrodes in three dimensional photo volta and light emitting diodes are also possible.A tenuous spherical silicon shell with a two micron thickness was wire bonded, an external circuit by omnidirectional printing. This method uses minimal contact pressure, which is highly advantageous for delicate devices. Also printed was a spanning interconnect for a silicon solar micro cell array in which the silicon micro ribbon elements are separated by a 33 micron gap.Silver interconnects for gallium arsenide based LED array with four by four pixels were printed. The LED array emitted uniform red light under an applied bias of six volts from a single pixel. The ability to print spanning electrodes enabled multilayer interconnection without the use of supporting or sacrificial layers.As a final demonstration, a complex 3D micro periodic silver lattice is printed by a five micron nozzle using layer by layer printing sequence. Once mastered, this technique can be done in a couple of hours that performed properly. Using this procedure, we have demonstrated ink synthesis printing of 1D to 3D structures and applications that include printed electrodes for electronic and optoelectronic devices.Ongoing work in our laboratory is now focused on extending this approach to biomedical applications using biocompatible inks. We are printing three dimensional scaffolds and microvascular networks for tissue engineering and cell culture. After watching this video, we hope you have a better appreciation for our direct right assembly technique.

planar-and-three-dimensional-printing-of-conductive-inks

Research

JoVE Journal

Bioengineering

A description of the methods used to convert an HP DeskJet 500 printer into a bioprinter. The printer is capable of processing living cells, which causes transient pores in the membrane. These pores can be utilized to incorporate small molecules, including fluorescent G-actin, into the printed cells.

Creating Transient Cell Membrane Pores Using a Standard Inkjet Printer

The methods described in this paper show how to convert a commercial inkjet printer into a bioprinter with simultaneous UV polymerization. The printer is capable of constructing 3D tissue structure with cells and biomaterials. The study demonstrated here constructed a 3D neocartilage.

Human Cartilage Tissue Fabrication Using Three-dimensional Inkjet Printing Technology

This paper introduces a 3D additive micromanufacturing strategy (termed ‘micro-masonry’) for the flexible fabrication of microelectromechanical system (MEMS) structures and devices. This approach involves transfer printing-based assembly of micro/nanoscale materials in conjunction with rapid thermal annealing-enabled material bonding techniques.

Micro-masonry for 3D Additive Micromanufacturing

A Cartesian bioprinter was designed and fabricated to allow multi-material deposition in precise, reproducible geometries, while also allowing control of environmental factors. Utilizing the three-dimensional bioprinter, complex and viable constructs may be printed and easily reproduced.

Viability of Bioprinted Cellular Constructs Using a Three Dispenser Cartesian Printer

This paper investigates the suitability of inkjet printing for the manufacturing of dye-sensitized solar cells. A binder-free TiO2 nanoparticle ink was formulated and printed onto a FTO glass substrate. The printed layer was fabricated into a cell with an active area of 0.25 cm2 and an efficiency of 3.5%.

Digital Printing of Titanium Dioxide for Dye Sensitized Solar Cells

This protocol describes a bioprinting methodology using an automated robotic depositing system that incorporates etched topographical guidance cues with the precision deposition of a cell bearing hydrogel bioink. The printed cells are directly delivered to the etched features and are able to sense and orientate with them.

Automated Robotic Dispensing Technique for Surface Guidance and Bioprinting of Cells

Here, we present a protocol to produce high-resolution conductive patterns using electrohydrodynamic (EHD) jet printing. The protocol includes two modes of EHD jet printing: the continuous near-field electrospinning (NFES) and the dot-based drop-on-demand (DOD) EHD printing.

High-resolution Patterning Using Two Modes of Electrohydrodynamic Jet: Drop on Demand and Near-field Electrospinning

Here we present a protocol for the fabrication of inkjet-printed multilayer sensor structures on additively manufactured substrates and foil.

Hybrid Printing for the Fabrication of Smart Sensors

A protocol for synthesizing inorganic-lead-halide hybrid perovskite quantum dot inks for inkjet printing and the protocol for preparing and printing the quantum dot inks in an inkjet printer with post characterization techniques are presented.

Inkjet Printing All Inorganic Halide Perovskite Inks for Photovoltaic Applications

Two recent technologies-tattoo and textiles-have demonstrated promising results in cutaneous sensing. Here, we present the fabrication and evaluation methods of tattoo and textile electrodes for cutaneous electrophysiological sensing. These electronic interfaces made of conductive polymers outperform the existing standards in terms of comfort and sensitivity.

Conformable Wearable Electrodes: From Fabrication to Electrophysiological Assessment

This paper provides a technique for manufacturing chip-based supercapacitors using an inkjet printer. Methodologies are described in detail to synthesize inks, adjust software parameters, and analyze the electrochemical results of the manufactured supercapacitor.

Elaborate Control of Inkjet Printer for Fabrication of Chip-based Supercapacitors

Learn direct right assembly for printing conductive microelectrodes using silver nanoparticle inks. This method enables fabrication of complex 3D structures for electronic and biomedical device applications.

Planar and Three-Dimensional Printing of Conductive Inks

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