Conference day 1 - Tuesday 13th November
After the introduction of the Masterclasses the conference began in earnest. It was a day split into two halves with keynote presentations in the morning and the conference splitting into 2 tracks for the afternoon sessions. Track 1 was applications but I chose to attend Track 2 which was devoted to Thin Film Transistor Circuits and Memory. This was also the first day of the exhibition.
The session started with a presentation from Peter Harrop, chairman of IDTechEx. Looking over a very full session room he observed that as Printed Electronics doubles in market size each year, so does this conference. My guess is that they will need more space next year. The first point in his slides continued this theme with a forecast of $300 billion by 2027 for this new post-silicon electronics. Peter also counselled getting away from defining this market by chemistry (organic vs inorganic) as it is what it does that matters. His view is that the first wave of this will not impact the market for silicon electronics but rather replace some printed output.
A presentation from Kovio announced for the first time at this conference their solution for Item Level Intelligence. Trillions of units are needed but only if they are below 5c (IDTechEx say 0.1 cents for the top volume). Kovio have a silicon ink and are demonstrating the world's first all printed silicon transistors with thousands in one circuit - well ahead of any organic transistor capability. The presentation featured poly-silicon inkjet printed on stainless steel to produce a 10 micron feature size. Kovio believe their technology will enable HF and UHF tags. They aim to commercialise by end 08. This announcement seems to have been featured in the Wall Street Journal today too!
Rather than the publicised presentation from Hasbro we had one from T-ink (short for Thinking ink). They are into paper related products and conventional printing, packaging with Mead Westvaco and have a lot of neat heated textile products.
We then had a presentation from Cubic on their contactless RFID solution for transport ticketing. Like many, I am familiar with their products - they do the Oyster cards for London Transport. This is a memory logic card but there is a need for intelligent products that are read/write. These are now taking volumes from magnetic systems as the costs are now comparable. Transit applications look set to be an early adopter of Printed Electronics.
After a break for networking and looking around the exhibition (see later) there was a presentation from Samsung Electronics on displays. The presenter described the advance of display technologies as consisting of 3 waves; notebooks, monitors and TVs. The presentation then went on to look at what could constitute the 4th wave. There will be inevitably be a need for higher resolution and speed (and therefore higher TFT current) but at lower cost. Printed displays could do the latter but at the moment will struggle with the former.
A presentation from LG Philips illustrated a world first - a high resolution full colour solution processed OTFT-LCD! It illustrated the development process from glass moving to flexible plastic and was a good illustration of the use of different printing technologies for each layer, taking advantage of their relative attributes. This was a theme also brought out in Masterclass 3 on Printing Technologies.
The final presentation of the morning session came from the National Science Foundation. This was good positioning as it pulled some of the issues together. It summarised some of the market research from IDTechEx and illustrated the growth of scientific papers in Organic Electronics as a metric of activity in the field. NSF see this as a key indicator of market potential. The presenter outlined the background, aims and mission of the NSF and showed that Printed Electronics sits well within their remit. They envisage growth in their funding in future years and are already supporting a number of projects of direct relevance to Printed Electronics.
Track 2 - Thin Film Transistor Circuits and Memory
This track started with a presentation from the Palo Alto Research Centre (PARC) who have an interest in displays and imaging sensors. Included in this talk was a large format x-ray imaging device on a flexible substrate. PARC are working on printed systems using inkjet and this sensor was patterned using inkjet on PEN. I had recently seen a reference to this work in Applied Physics Letters. The presentation showed the importance of annealing organic semiconductors to improve mobility. A further important point was also made - that mobility decreases with surface roughness. This is important particularly as we move on to printed electronics on paper substrates, the subject of my own presentation the following day.
This presentation then moved on to discuss degeneration mechanisms for these devices. It was shown that they degenerate in air in the absence of light so photochemical effects are not the primary issue. Perhaps surprisingly storage in pure oxygen did not produce a problem. Keeping away from water vapour was shown to be helpful but the main problems seem to stem from atmospheric pollutants such as ozone (1 to 10 ppm for <30 seconds) and sulphur oxides. These can be kept away from the devices by encapsulation. Given that this is a known issue with the colorants in conventional inkjet printing there is probably some knowledge to be gained from these applications.
A presentation from STMicroelectronics looked at materials for "post silicon" electronics. It concentrated on soft lithographic methods and nano-imprint lithography. The resultant devices were characterised by conventional methods. The presentation gave good examples of synergistic efforts between chemical companies, advanced tool manufacturers and end users.
ORFID Corporation presented next with a description of their vertical transistor architecture. They have designed a vertical organic semiconductor FET (VOFET) and a light emitting version (VOLED). The layers are laid down onto glass by thermal evaporation and spin coating. A presentation from HelioVolt described the technique of Reactive Transfer Printing. This is an impact printing method where 2 plates each containing a reactant are pressed together in a printing process. The reaction proceeds to produce the desired material. This technique was demonstrated to print CIGS for photovoltaic applications.
Track 1 - Applications
I missed the first presentation as I got into some interesting discussions with other delegates about printing onto paper. This was a good illustration of the strengths of these meetings - it is not just about what you hear in the formal sessions!
A presentation from Motorola started with the valid point that although silicon based semiconductor development is often described by Moore's Law printed electronics can be described as "More than Moore" due to the potential for explosive growth. The presenter then went on to look at printed sensors and the trend towards wholly printed sensors and RFID tags.
We then had a presentation from Elumin8 on their electroluminescent system followed by a final session from Raghu Das of IDTechEx on smart skin patches, the 4th generation of these requiring progressively more electronics.
The day finished with a drinks reception followed by the conference dinner. A great time was had by all with a lot of conversation covering the days events.
Conference day 2 - Wednesday 14th November
Day 2 of the conference and we split into 3 tracks covering 5 topics. I chose to spend some of my time in all 3 tracks. My only fixed point was my presentation on the use of paper in printed electronics late morning so I took the opportunity to sample what was on offer.
Track 1 - Displays and Lighting
This track started with a presentation from Cambridge Display Technology. Their vision is to displace LCD for display by 2020 - there is already a Nokia phone using their technology. However, OLED technology currently has a 2x price premium over LCD. The plus point is much lower power consumption which is particularly important for handheld applications. CDT are working towards flexible substrates but the substrate must also act as a barrier layer too.
CDT illustrated some major advances in blue OLED lifetime, with a T50 of 10,000 hours. While this is not (yet) good enough for domestic TV applications it is deemed to be sufficient for mobile applications. They are evidently making advances with printing techniques too, showing some good pictures of the coffee ring effect in practice. They are exploring optical feedback systems for interlayer registration with Toppan and looking at Vitex Barix barrier systems.
A presentation from Eastman Kodak featured display backplane technology using zinc oxide. They believe this confers transmission and efficiency advantages. It also means that the fabrication can be done in air.
After a break for some of the other sessions I returned for the presentation by the US Display Consortium (USDC). They are sponsoring a number of projects and I was particularly taken by their work on interlayer registration. They have a project on self-aligned imprint lithography that looks to be particularly interesting.
We then had a presentation by 2 people from Quantum Paper. The company is currently undergoing a name change to Nth Degree. They are initially targeting the retail point-of-purchase, direct marketing, magazine inserts and signage markets moving on to flat panel display and packaging next year. Theirs is a printing technology but there was little said on this - some is electroluminescent but "not all".
Arizona State University have been doing some very interesting work on Printed Electronics. Included in this is a coated paper from Agfa, wall to wall solar panels and made the first demonstration of inkjet printed quantum dots.
A presentation from VTT described their work on the OLLA project and the use of gravure printing to fabricate continuous films for OLEDs. Gravure printing has the advantage that you can use the same fluid rheology as used for spin coating.
MicroEmissive Displays presented their very small displays used for video glasses and electronic viewfinders. It is based on silicon chip technology but at this size there is no need for flexibility. They used a filtered white OLED system, sacrificing efficiency for better colour stability with device ageing. At present the POLED is spin coated but they are looking at inkjet technology as an alternative to this.
The final presentation in this session was from iSuppli and looked at market drivers for flexible displays. The market was segmented by "flexibility" from slightly bendable to fully rollable. I found this a useful way to consider the issues involved.
Track 2 - Photovoltaics and Batteries
I attended the presentation from Enfucell featuring their Zn/MnO2 battery technology. This is roll-to-roll printed and uses paper as the separating layer. This would be a good technology for some of the novelty applications discussed at this conference.
Track 2 - Materials and Substrates
I attended the conference as a presenter too. My contribution at the start of this session was on the role of paper in the future of printed electronics. Paper and cardboard are universally accepted media both in domestic and industrial environments. Unfortunately it is not a particularly easy substrate for printed electronics. The presentation looked at some of the early successes of paper and card and summarised the ways forward. We have to look at paper design criteria and printing techniques. For this latter point the masterclass on printing technologies is particularly useful.
This session also contained a presentation from Sun Chemicals who are leveraging their experience in conventional printing into printed electronics.
Track 3 - Sensors and Sound
I was interested to view the BioIdent Technologies presentation and was not disappointed - it was a very slick and animated performance featuring their lab-on-a-chip system. Their inkjet based fabrication system is capable of doing 40,000 square metres of material pa and they are currently in pre-production with a number of OEMs.
The 2 days of the conference also featured an exhibition from companies and organisations active in this area. Serving lunch and coffee in this area served to ensure significant foot traffic through the area and the booths certainly looked to be busy. Here is a summary of a few I visited.
I spent some time on the Cintelliq stand discussing the organic semiconductor industry. They do a well produced newsletter on this industry that made an interesting read.
IDTechEx and Printed Electronics World had booths and showed some interesting examples of printed electronics together with their library of market reports. I mark the occasion Printed Electronics World had been produced as a high quality print version too.
The Organic Electronics Association (OE-A) were giving away the 2nd edition of their brochure which is a mine of information. Their pack also included a set of organic electronic demonstrators and interactive electronic paper cards complete with reader.
RadTech are a trade association for the UV and EB curing industry and had some of their reports on show. I have an interest in their technology as I believe that it has much to offer printed electronics.
Sonoplot were showing their picolitre scale fluid dispensing system. This seemed to be an interesting alternative to inkjet for linear features and I left with a number of scientific papers to read about their system. Unidym had samples of their carbon nanotube products on show. They are producing conductive coatings of these and seem to hold a significant number of patents in this field.
Masterclass 3 - Thursday 15th November
On the final day of the conference I attended the Masterclass on Printing Technologies. This was delivered in 3 parts.
First of all Bruce Kahn of Printed Electronics Consulting described the systematics and principles of printing. Bruce went through the various impact and non-impact printing processes that have been developed or evolved in conventional printing. As he described these he showed with examples how these can be used to fabricate printed electronics and displays. By going through the advantages and disadvantages of each he illustrated where each technique may find a niche in printed electronics.
Mike Renn of Optomec then described their M3D Aerosol Jet Printing system. This is finding use in the fabrication of photovoltaics where the ability to fabricate long continuous straight conductors is of value.
Finally Susann Reuter of IDTechEx described some examples of Printed Electronics to pull the whole masterclass together. Although this is a huge topic that could certainly use more than the 3.5 hours allotted it was a great introduction to the topic. I would recommend this to anyone attending a future conference.
This was a great end to a 4 day meeting. I certainly feel that I took away a great deal of valuable information from the event. I look forward to the next time!
by Dr Alan Hodgson
Learn more at the next leading event on the topic: Printed Electronics Europe 2020 on 13 - 14 May 2020 at Estrel Convention Center, Berlin, Germany hosted by IDTechEx.