Part 1

Background What are polymer electronics? What makes polymer so suited for electronic applications? Polymer Devices Applications and Areas of Research Printable Electronics Advantages and Disadvantages Summary M. Rosado EECE 487 Spring 20092

In the early 1970s, Alan J. Heeger, Alan G. MacDiarmid and Hideki Shirakawa collaborated and discovered that the electrical conductivity of conjugated polymers could be controlled by doping Polyactelene and iodine The conductivity of this doped material approaches the conductivity of the best available conductor This was one of the first known examples of a conductive organic polymer Researchers were granted a Nobel Prize in 2001 Paved the way for organic/polymer electronics M. Rosado EECE 487 Spring 20093

 A polymer is a compound consisting of a long chain of repeating monomers  Typical polymers - plastic, rubber  Polymer  Polymers electronics are often grouped under organic electronics because they are carbon based  Polytronics – polymer + electronics M. Rosado EECE 487 Spring 20094

 Polymers can be very easily processed from solution  Number of low cost application techniques can be applied  Mass production  Enhanced flexibility allows for more applications M. Rosado EECE 487 Spring 20095

6  TRANSISTORS - organic field effect transistor to control current and voltage  OFET-The transistor is the basic building block for integrated circuits. A typical polymer transistor contains 4 layers:  On the substrate, there is a first contact layer, which is structured to form the base of a transistor with two contacts: source and drain. ▪ These contacts are covered by the polymer semiconductor.  The next layer is the polymer insulator, which separates the gate contact layer form the semiconductor.  The top layer is the gate contact layer.

M. Rosado EECE 487 Spring  Polymer Diode  In organic diodes, the rectifying contact (so called Schottky contact) between the organic semiconductor and specific metals is used.  The charge carriers can pass this metal-semiconductor contact only in one direction.  Diode allows current flow only in forward direction, whereas in the reverse direction the current flow is blocked.  Polymer Capacitor  The capacitor consists of two electrodes which are separated by a dielectric (insulator)

M. Rosado EECE 487 Spring  Polymer Inverter  A polymer inverter consists of two organic transistors  Basic circuits for the implementation of logical functions like NAND, NOR, NOT  Polymer Ring Oscillator  The ring oscillator is a relatively simple circuit consisting of a series of several inverters  Can be used in ICs to generate a clock signal