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Electronic chips as ink

What if we could print smart materials with the throughput and cost of laser printers, but with the precision and functionality of nanotechnology?  

Electrophotography, or Xerography, is a widely used technique to print photos and books on demand ., This process places colored toner particles on digitally designated locations to form patterns at high speed, handling > 108 particles per second for only penny a page.  We realized that this same process can be used to handle microscopic chips, instead of toner to form complex electronics circuits on-demand, making electronics fabrication as simple as printing a document.

If we can improve the precision and accuracy of the typical electrographic process to assemble individual components into well-defined locations and well-defined orientations, we could build a massively parallel digital manufacturing tool to produce complex heterogeneous systems at unprecedented speed.

PARC aims to build the first digital MicroAssembly Printer, where the “inks” are micrometer scale particles or computer chips, and the “image” outputs are macro-scale assemblies (Figure 1).  This tool could enable new high performance electronics (sensor arrays, displays, antennas, etc) which are flexible, heterogeneous, and quickly fabricated, but with the complexity of modern integrated circuits.  The ink could be pre-fabricated active electronic devices (amplifiers, memory, sensors, 1-100s of µm in size), and the image output could be a functional electronic system (cm to meter scale).  Similarly, with microparticle inks, the printer could enable large, engineered, customized microstructures, such as short-run production of metamaterials with unique responses for secure communications, surveillance, and electronic warfare. Overall, this research aims to combine the desirable capabilities of high throughput, complexity, heterogeneity, rapid prototyping, and programmability, to form a new manufacturing capability (Figure 2).

In a process similar to the familiar xerographic printing of ink toner on paper, we are using electrostatic printing techniques to assemble of micro-objects.  As an initial demonstration of the process, 100 µm scale silicon chips (see image above) were assembled into an array with dynamic electric fields (Figure 3), and transferred and interconnected (Figure 4).  Current research is focused on advancing the technology for applications in metamaterials and solar arrays, funded by DARPA and the DOE ARPAe respectively.

Figure 1.  Schematic of micro-assembly printer system.  Ink bottles, consisting of micro-objects in a solution, are rapidly assembled into custom patterns and interconnected to form complex, heterogeneous electronics systems and smart matrials with engineered microstructures.


Figure 2.  The PARC printer aims to combine the best properties of other system on a chip, pick and place and xerographic technologies.


a)      b)

Figure 3. Photo of four silicon chips (300 µm× 400 µm) on four spiral electrode arrays.  Chips are moved from disordered positions (a) to an ordered 2 × 2 array with four phase traveling wave patterns. No feedback is used so the process is readily scalable to many chips.   See attached video.  [reference Applied Physics Letters paper below]


Figure 4. Four fundamental steps in the proposed micro-object printing process. (a) Encoding micro-objects with charge patterns to make “inks”. (b) Image development. Random micro-objects are assembled to pre-defined location using a dynamic template and directed assembly process. Left inset shows a fixed-pattern version of the dynamic template. Right inset shows a 4x4 programmable electrode array. (c) Transfer. The micro-objects are transferred to the final substrate through an intermediate roller. Top inset shows an example of the apparatus. Bottom left inset shows four assembled chiplets on intermediate transfer substrate. (d) Interconnects. The micro-objects or chiplets are interconnected using photolithography (top-right inset) or ink-jet printing (middle-right inset) to give complete circuits (bottom-left inset; 4 chiplets).  [reference Applied Physics Letters paper below]


Open and closed loop manipulation of charged microchiplets in an electric field Lu, J. P. and Thompson, J. D. and Whiting, G. L. and Biegelsen, D. K. and Raychaudhuri, S. and Lujan, R. and Veres, J. and Lavery, L. L. and Völkel, A. R. and Chow, E. M., Applied Physics Letters, 105, 054104 (2014), DOI:http://dx.doi.org/10.1063/1.4891957




Markus Larsson
Business Development
+1 650 812 4717


in the news   view all 

DARPA Picks 10 to Build Nano-based Products
7 January 2016 | Defense Systems

Chips off the Old Block
6 December 2014 | The Economist

Micro Chiplets
8 August 2014 | MIT Technology Review



blog posts   view all 

Think 3D Printing is Cool? How About Printing Your Own Electronics
posted 19 November 2013

The history of printing spans centuries and it’s one that is rich in breakthrough innovations and societal impact – from block printing to movable type to xerography to PARC’s own invention of the laser printer. Now printing is blazing a new trail and leaving some of its paper roots behind.  Innovation is now focused on printing electronics, sensors, or circuits