Printed Electronics vs. Silicon—Getting the Priorities Right
Although the capabilities of complex silicon chips increase at a rapid pace, there is little or no reduction in cost of the simplest silicon chips. These have stuck at about five cents for decades. The cost of a chip factory and the cost of research to improve chip production is rising exponentially so there is no reason to believe that the simplest chips will get significantly cheaper in future. An added concern is that these chips are the ones that make little profit so they are the first to be rationed and suffer price hikes when there is a chip famine i.e. when demand exceeds capacity as happened in 1999 and, to a lesser extent, in 2004.
Contrast printed electronics where production facilities are relatively cheap and easy to expand and the technology is coming down in price. Printed electronics will therefore increasingly replace silicon chips at the low end and one can say much the same thing about replacing other conventional components, including displays. However, it will be many years before very high frequency performance is economically feasible for most forms of printed electronics so even simple microprocessors and the UHF and microwave part of the RFID market, to take examples, will be served by silicon chips for many years yet.
Are the Priorities Right?
Given the driving forces for printed electronics and the limitations of silicon chips we can assess the appropriateness of the priorities of those developing and exploiting the technology. We conclude that there is too little emphasis on creating new applications and exploiting existing printed electronic technology in the marketplace. Many companies are developing inks intermediate in conductance between carbon and silver based ones. Such inks will have enormous potential if they have the right cost, printing characteristics, environmental credentials etc. In displays, the number of companies attempting to get Organic Light Emitting Diodes (OLEDs) into the market is about ten times the number working on all other types put together. The market potential is more balanced than this, with a wide variety of price performance compromises needed in particular. In thin film transistors, most developers are concentrating on improving the cheapest technology - that based on soluble polymer semiconductors. This correctly reflects the market potential.