When looking through granted patents in any technical field it is always a concern if one turns up with broad claims that might impact a wide range of products or manufacturing processes. Recently I came across one in the printed electronics field which might just be in that category. Read on to see what it is all about.
US7982296 was granted on 19 July 2011 to the University of Illinois and has the title “Methods and Devices for Fabricating and Assembling Printable Semiconductor Elements”. The abstract caught my eye because it was referring to flexible devices made on substances comprising polymeric materials and also to stretchable structures.
The invention provides methods and devices for fabricating printable semiconductor elements and assembling printable semiconductor elements onto substrate surfaces. Methods, devices and device components of the present invention are capable of generating a wide range of flexible electronic and optoelectronic devices and arrays of devices on substrates comprising polymeric materials. The present invention also provides stretchable semiconductor structures and stretchable electronic devices capable of good performance in stretched configurations.
I was able to trace the history of this application and found that the earliest documents associated with the filing were back in 2004 and that two patents were eventually granted, the earlier one related to the method for assembling the devices (US7622367) published on 24 Nov 2009 and this one just published being for the devices themselves. The INPADOC patent family now consists of over 30 documents across several countries including Japan, Korea, Taiwan, and China.
The first claim is the broad one which I believe may give some concern to a number of manufacturers involved in printing inorganic semiconductors. It reads:
1. An electrical device comprising: a first electrode; a second electrode; and a printable semiconductor element positioned in electrical contact with said first and second electrodes, said printable semiconductor element comprising a unitary inorganic semiconductor structure having at least one cross sectional dimension greater than or equal to about 500 nanometers.
The other 8 claims are all dependant claims and further refine claim 1. A number of examples are included illustrating the range of devices in mind, some involve dry transfer printing, others solution printing.
The patent description is remarkably detailed with several pages of background references and 46 figures one of which is included below.
FIG. 26A illustrates the steps used to fabricate exemplary bendable thin film transistors devices of the present invention.
If you wish to explore the patent further it is best to review the pdf file which can be downloaded from the Espacenet website.
As always, please leave a comment if you want to discuss this further and visit my IPScope website for details of a range of Strategic IP Management services including patent searches.