Goals. Printable Electronics at R I T. Printing Methods. How do you print circuits?

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1 Goals at R T Design and print test patterns and antennas for applications Determine printing process capabilities for printing devices Study physical and electrical properties of printed features Fabricate a working device using printed antennas Use of traditional printing processes for production of circuits. nexpensive, high volume circuit production. Allows anybody with the proper printing equipment to try circuit production. Can be printed on a variety of materials (plastic or paper for example) and surfaces (glossy, matte, etc). Less wasted material. Uses process-specific conductive inks to print circuits directly. igh speed inker used for coating plates in ink ow do you print circuits? Printing Methods Production of a plate, drum or other source object for printing. nking or direct printing depends on printing process in use. Various inks require different curing times and temperatures. Metallic inks cure differently from conducting polymer inks. Substrate must be capable of handling curing temperatures necessary. Some inks can be cured at relatively low temperatures. Silver metal inks can cure at <200 C, much less than the melting point of silver ( C) Screen printing and inkjet are common methods. owever they have some disadvantages: Slow, cannot be used for high volume. Screen printing lays down a very thick layer of ink, and cannot resolve fine lines for transistors and other smaller features. nkjet printing produces satellites or small drops of ink that splatter outside of the intended print area. We are experimenting with the use of flexography, gravure and lithography, which are high volume processes and are widely available.

2 Parmod nks Silver flakes Silver nanoparticles Silver Metalo Organic Decomposition (MOD) compound (soap) Silver neodecanoate US Patents 5,882,722; 6,036,889; 6,379,745 Curing printed inks Many inks require long periods of time (>18 hours) or high temperatures to properly cure. This results in slower production and a reduction in the number of usable substrates. Parelec Parmod inks use silver nanoparticles to weld together larger plates at low temperatures making fast low-temperature curing possible. Antenna Properties Coil resistance Currently: 86 Ohms Target: 50 Ohms Line height Average line height: 3.5 microns Microstructure Cross section of printed line. Top of printed line Close-up of cross section Microstructure Replacing barcodes with antennas Cross section of printed sample on paper Bar Codes Pros: nexpensive Do not require specialty inks Can be printed on almost any substrate Cons: Must be scanned optically, within the line of sight Limited data capacity Radio Frequency dentification Pros: Large data capacity Can still be scanned even if visually obscured Allow inventory management and theft detection. Cons: Expensive More complex to produce Top of printed sample on paper

3 Producing a passive Antenna coil is printed using conductive inks and cured. A micro- chip is attached to the antenna to produce the complete tag. Eventually the microchip could be printed as well to further increase production capacity. What is Radio Frequency dentification? Most common s are passive which use an antenna and a microchip. These are powered by energy obtained from radio waves received by the antenna Active tags use batteries to power a chip and an antenna. Overview The two main components of inductively coupled systems are the data reader and any number of transponders (i.e., the D tags). n order to detect the presence and read the D code of the transponder, the reader generates a magnetic field by passing current through a coil antenna. This magnetic field induces a current in the antenna coil of the transponder. This current is rectified, stored, and used to power the integrated circuit component of the D tag. Overview The C chip contains the code belonging to the D tag. Once activated, the transponder generates a magnetic field and transmits the code for the reader to receive. When received, the code can be used by any application, whether it is for security, inventory, or some other purpose. The reader may also transmit data to be written to the transponder. The two main components of inductively coupled systems are the data reader and any number of transponders (i.e., the D tags). The coupled magnetic field between the tag and the reader provides a two-way communication channel. The reader would likely be connected to a PC or network. Tag Coupled S 11 for Coil on Mylar Substrate S. Cichos, J. aberland, and. Reichl, Performance Analysis of Polymer based Antenna-Coils for, in Conf. Rec EEE Polytronic Conf., pp

4 S 11 for Coil on Paper Substrate Future Applications More complex circuits Thin film transistors Backplanes for displays Sensors Micro Electro-Mechanical Systems (MEMS) Other multi-layered devices Team Members Support Dr. Bruce E. Kahn Professor maging and Photographic Technology Materials Science and Engineering Rajiv Sangoi Graduate Student Materials Science and Engineering Michael D. Seymour Graduate Student Electrical Engineering Carl Smith Undergraduate Student maging and Photographic Technology Dan Clark Print and mage Quality Technologist, Printing Application Laboratory Ken Chin Director T Collaboratory Michael Kleper Paul and Louise Miller Distinguished Professor School of Print Media Bill Garno Director Printing Application Laboratory Dr. Jayanti Venkataraman Professor Electrical Engineering Theory? Questions Current in a loop of wire will induce a magnetic field of strength around the wire according to the right hand rule (RR) Also, a magnetic field of strength will induce a current in the a loop of wire. induced induced

5 Theory (Continued) The direction of the induced magnetic field is given by the right hand rule, while the magnitude is given as: induced = 2 b Circular Loop of radius b A m induced (At the center of the loop) Square Loop of side w 2 2 = πw D. K. Cheng, and Wave Electromagnetics. New York: Addison-Wesley, 1992, pp A m n order to detect the presence of and read the D code of the transponder, the reader generates a magnetic field by passing current through a coil antenna. Tag Generates This magnetic field induces a current in the antenna coil of the transponder. This current is rectified, stored, and used to power the integrated circuit component of the D tag. Tag The C chip contains the code belonging to the D tag. Once activated, the transponder then generates a magnetic field and transmits the code for the reader to receive. When received, the code can be used by any application, whether it is for security, inventory, or some other purpose. Tag Tag Generates S. Cichos, J. aberland, and. Reichl, Performance Analysis of Polymer based Antenna-Coils for, in Conf. Rec EEE Polytronic Conf., pp