December 7, 2011 - The IDTechEx combined Printed Electronics USA 2011 and Photovoltaics USA 2011 event opened November 30 in the Santa Clara, CA convention center with 1200-1250 registered and walk-in attendees, comparable to 2010 attendance.

A morning of keynote addresses filled the large auditorium to about 90% capacity before the crowd split up for the parallel tracks. The speakers in this opening track personified the notion of customer pull, presenting a variety of new applications that have been or are being brought to market, as well as a wish list of things they wish they had. Technical content was hard to find; this market is all about the marketing. Technology is tolerated to the extent that it is indispensable.

Kenneth McGuire, principal scientist at Proctor & Gamble, opened the conference with a presentation on packaging applications for consumer products. Watch your store shelves for a Puffs tissue box with a Christmas EL lighting display, powered by two AA batteries. Since most applications require the integration of logic, memory, display, and power with the overriding constraint of low cost, there is still a lot of development needed before every package on the store shelf is literally shouting for your attention. Expect broad market introduction to be slow.

Michael Londo, director of open innovation at MWV Packaging, discussed the search for matches between available technology and market needs. Collaboration with the printed electronics program at Western Michigan University and with Vorbeck Materials has played a critical role in bringing some new consumer product security systems to market.

Warren Kronberger, R&D director for The Marketing Store, showed several commercial packaging campaigns from other parts of the world that make US marketing look just a tad primitive. Integration of PV power supplies in locations where plug-in power is not readily available is relieving some pressure on developing inexpensive battery technology.

Andrew Ferber & John Gentile, co-chairmen of T-Ink, spoke of the company's evolution in printed electronics from toys to aerospace over the past decade. Their strategy of using low-tech products to seed discussions for products now being implemented in automobile overhead consoles and smart wear has provided them with steady growth in both market penetration and product complexity. Their touch panel design places the capacitive layers much closer to the panel surface, resulting in a higher s/n and 10× faster response time than conventional touch panels. Ink formulations are held as trade secrets within an IP portfolio that focuses on manufacturing processes and applications.

Brian Fuchs of US Army ARDEC talked about energetic (i.e. explosive!) ink development for armament applications. The drive for smart munitions has resulted in a trade-off between space for electronics and space for ordnance. Some of this space and weight can be recovered by using a flexible printed electronics detonator. The design concepts are not unlike fuse technology in conventional electronics. Among the enabling components is a printed graphene supercapacitor (60F/g). Collaborators include the National Nanotechnology Manufacturing Center and Hamilton ITS. Achievements include the first syringe printable secondary explosive. Given the nature of the business, ROI is not an issue.

Jeff Duce of Boeing Research & Technology talked about aerospace applications for printed electronics. A reduction of 1% in aircraft weight equates to billions of dollars in annual operating cost savings for an airline. The 747-8 aircraft now incorporates a printed electronic damage detection sensor for the fiberglass leading edge wing flaps used to create additional lift for takeoff. Other fun facts: aircraft tires contain a heat sensor system that can deflate the tires if they overheat, a sensible alternative to exploding. Reliability requirements for many components is the full 30-year life span of the aircraft.

Sriram Peruvemba, chief marketing officer of E Ink Holdings, lodged the unusual complaint that "my eReader ate the library." E Ink is now owned by a paper company, and reports that paper books still outsell electronic alternatives. The documented decline of library usage can be traced to ~1997, several years before the introduction of ePaper readers. Current eReaders display at 150-200dpi; new products hitting the market operate at 300dpi and claim visual appeal superior to paper. The E Ink Pearl device claims 90% market share, with over 25M units sold in 2011. The greatest pull for eReaders in education is in China, India and Brazil. One novel product is an oversized double page eReader built into a podium that can be used by a conductor to display a full musical score. The Q&A seemed to focus on the loss of serendipitous discovery opportunities for students that comes from electronic searching for specific reference materials rather than browsing a physical library or journal and stumbling across a related article of interest.

David Hamby of Osram Sylvania talked about the migration of printed electronics into the lighting industry, specifically the intersection of inorganic LEDs with printed electronics. He spoke glowingly (confession: pun intended) about direct mounting of LED devices on printed circuitry for large area lighting. While many of the tradeoffs can be accommodated, heat dissipation remains the dominant challenge. Lateral heat spreading is the direction in which this industry segment is heading. The afternoon schedule included the usual bifurcation into three parallel session tracks. This renews my longing for a macroscopic quantum world, in which I could attend all three sessions at once until someone asks me which session I am attending. My chosen sessions are described herein.

Vivek Subramanian from UC Berkeley opened the session with an update on where printed consumer electronics is heading, not your conventional topic for an academic. Devices like smart phones will soon come with near field communication (NFC) capability, which will enable simple communication with very many more devices or objects. Only about 300 transistors are needed to facilitate the logic for this communication. Their lab is developing a printable Zn-Ag battery that has the energy density of Li-ion without the air sensitivity. Careful crafting of fluid mechanical properties allows rapid printing (2 ft/sec R2R) of transistors without stringent alignment requirements, effectively a self-assembled process.

Hideo Nakako at Hitachi Chemical talked about their new offerings of dielectric and Cu inkjet and screen printing inks. The Cu process requires heating to 180°C in an unspecified reactive gas for 15-30 minutes in a process that is described as "not sintering."

Chung-chin Hsiao, Polyera's VP of business development, provided a comparison of their favorable TFT performance against that of competitors. Their OPV offering uses a thick (250nm) active layer with an inverted structure, obviating the need for oxygen-sensitive materials and providing improved long-term stability.

CEO Scott White of PragmatIC Printing talked about systems integration and applications development of printed logic. Their claim to fame is a R2R-compatible embossing process that enables sub-micron features with self-aligned characteristics that minimize overlay requirements.

Janos Veres of PARC presented their perspective on new developments in printed logic and memory. Their complementary organic TFT with Ag leads have well matched mobilities for both the p-type and n-type devices of ~0.1cm²/Vs @ 20V. He also presented a memristor counting logic device powered by piezoelectric motion energy capture, no batteries, and no transistors. Inkjet prototyping used a minimum 35μm feature size; smaller resulted in printing defects.

Senior VP Shiv Chiruvolu of Nanogram (now a part of Teijin Group) spoke on silicon nanoparticle inks and pastes for TFT and PV applications. Such transistors are capable of mobilities in the range of 1-100cm²/Vs when the Si particle size is on the order of 100nm and less. Uniform spherical Si particles are fabricated using CO₂ laser pyrolysis. Patterned Si films can be formed by inkjet, spin coating or screen printing. The resulting nanoparticle film must be sintered using heat or radiation to form the functional conducting or semiconducting film. 3 Warren Jackson of HP talked about their R2R self-aligned imprint lithography (SAIL) technique applied to large area metal oxide electronics. The metal oxide systems (In:Ga:Zn and Zn:Sn, for example) have mobilities up to 20cm²/Vs and are chosen to avoid certain shortcomings of α-Si and low temperature polysilicon.

The meeting schedule nicely allowed adequate time for perusing the exhibitor floor during the breaks. Among the more interesting suppliers I talked to on the exhibition floor was Seashell Technology, which offers a conductive ink based on Ag nanowires on the order of 50-150nm diameter and lengths up to 100μm. Where many Ag inks require 50%-90% solids content for functional conductivity, this material has competitive conductivity with single-digit-percent solids. This sparseness makes it a reasonable replacement candidate for ITO in TCO film applications, with 90% transmission at 10Ω/sq. Other suppliers are developing competing ITO replacements using Cu nanowires, CNT or graphene.

The conference also included nine Master Courses on printed electronics topics from November 29 to December 2.

Michael A. Fury, Ph.D, is senior technology analyst at Techcet Group, LLC, P.O. Box 29, Del Mar, CA 92014; e-mail mfury@techcet.com.