The ability to bring concepts from idea to an actual prototype is often one of the most challenging steps for printed electronics researchers. Precise laboratory equipment is essential to bring these projects to fruition.
 
This is where SonoPlot, Inc.’s expertise in microscale printing of liquids comes in. SonoPlot’s Microplotter systems use controlled ultrasonics to dispense picoliter volumes of fluid in a manner that resembles a pen plotter, but on the microscale. As a result, Microplotters can print materials such as nanometallic silver, carbon nanotubes, graphene, DNA and proteins in microscale spots, lines or other shapes with ease and flexibility.
 
SonoPlot’s Microplotter systems were initially designed at the University of Wisconsin-Madison for biologic liquids, but the printed electronics field has proven to be an ideal market.
 
“SonoPlot was founded out of research performed at UW-Madison into a means of printing high-resolution biological microarrays,” said Dr. Brad Larson, SonoPlot’s co-founder and CEO. “The technology developed in that project turned out to be commercially viable, so SonoPlot was founded to bring it to market. While originally conceived as a means of printing biological solutions at a high resolution, we were surprised at the huge response we got from researchers and companies in the field of printed electronics.”
 
The ability to print such fine detail fits perfectly with the requirements of printed electronics developers.
 
“These systems can print droplets and true continuous lines or arcs with feature sizes that are typically in the 20-50 micron range, but we’ve been able to print 5-200 micron wide features with specific material combinations,” Dr. Larson noted. “These systems can handle everything an inkjet can, and much more, with the ability to print liquid viscosities from 1-450 centipoise.
 
“Today, the vast majority of our business is in the field of printed electronics, and our products have been tuned to address those needs,” added Dr. Larson. “We’ve worked with a number of other companies in the field to build partnerships that let us suggest complete solutions to our customers. The interest in this area only seems to be growing over time, as are the number of companies involved.”
 
SonoPlot’s products are built for research and rapid prototyping in printed electronics, materials research and the life sciences.
 
“The majority of our customers are looking to prototype microelectronic designs, sensors or novel materials,” said Dr. Larson. “As a result, the applications of these customers tend to be diverse, ranging from printing flexible circuitry for implantable sensors to forming microscale polymer lenses. The majority of our customers use our systems for printing electronics and sensors.”
 
The ability to print a wide range of some of the most challenging materials is a major advantage of the Microplotter.
 
“The most prominent advantage of SonoPlot’s Microplotter systems over existing liquid dispensing technology is our ability to handle a broader range of materials,” Dr. Larson observed. “Nanometallic inks, such as silver, tend to be fairly popular, but customers use a range of different materials in our systems: graphene, carbon nanotubes, conducting/semconducting/insulating polymers, oxide nanoparticles, microparticle mixtures, proteins, and oligonucleotides are just some examples.”
 
The Microplotter systems are not limited to dispensing droplets. It can produce true straight lines or arcs drawn in a continuous motion, rather than composed of overlapping droplets.  “Customers have printed polymer waveguides with extremely straight edges, for example,” Dr. Larson said.
 
Although it is feature-rich, the Microplotter system remains affordable as well.
 
“Our systems are also very affordable when compared to competing systems, and are priced to fit within the budget of even smaller research groups or companies,” Dr. Larson noted.
 
Unlike inkjet technology, which ejects droplets, the Microplotter is more like a pen plotter, directly dispensing droplets or true continuous features. The patented ultrasonic pumping action that drives the dispensing is at the core of the Microplotter.
 
“Our use of controlled ultrasonics and a direct-write means of dispensing gives us many advantages,” Dr. Larson said. “It is a unique technology that sets our products apart from others. We believe that our focus on smaller research labs and companies has allowed us to address needs that others have not, and we’d like to further expand into other areas where needs are not being met by existing printing systems.”
 
Printed electronics is a field that offers many different possibilities, using a variety of materials in all sorts of configurations. Dr. Larson said that this has led to continuous innovations for the Microplotter.
 
“Strong customer demand pulled us into the field of printed electronics, and we keep being surprised with what people want to do with our systems,” he noted. “We’ve worked with our customers to craft hardware and software tuned to the needs of printed electronics, and the feedback from these efforts has been very positive.
 
“Every new publication or product that wouldn’t have existed without our systems is a source of pride for us,” Dr. Larson added. “Positive word-of-mouth from these publications and from existing customers has led us through strong growth.”
 
Dr. Larson sees an excellent future for the printed electronics field, and anticipates that ultimately, future expansion will be driven by new applications.
 
“In the lifetime of our company, we’ve watched as printed electronics tradeshows have gone from the size of hotel lobbies to the largest convention centers they can get,” he said. “Complementary technologies like 3-D printing have grown alongside this, and we only see the need for rapid prototyping, personalized fabrication, and research expanding in the near future.
 
“We believe there is strong potential in the coming together of new additive manufacturing technologies that we’re seeing today,” Dr. Larson concluded. “This is reflected in many of the presentations seen at recent printed electronics and material science conferences, and we think we’ll see a lot more of this in the next few years. The customer needs driving the evolution of printed electronics are stronger than ever, which speaks positively for the growth of this market.” 

SonoPlot’s MicroplotterProto