Ananth Dodabalapur

SSCS sponsors 2nd Annual Organic Microelectronics workshop

The second annual Organic Microelectronics Workshop will take place in downtown Toronto on 9–12 July, 2006. It is an unusual interdisciplinary conference, established by the American Chemical Society (ACS), the IEEE Components Packaging and Manufacturing Technology Society (CPMT) and the Materials Research Society to bring the communities into lively discussion across boundaries. Invited speakers are from around the globe, and represent both industrial and academic communities, with heavy representation from companies trying to develop commercially attractive devices.

Elastomeric molding, stamping and near-field photolithographic methods for integrated optics and electronics

Summary form only given. Our recent research focuses on the development and use of rubber stamping (microcontact printing-/spl mu/CP), optical near-field methods that use conformable photomasks, and molding techniques that rely on elastomeric transfer elements. We explore, in particular, their applicability to the fabrication of certain systems in integrated optics and organic electronics. In this talk, I provide an overview of these soft lithographic techniques by highlighting their advantages and disadvantages compared to more established methods. The fidelity of the molding procedures are demonstrated through the fabrication of working plastic lasers that use molded distributed feedback (DFB), distributed Bragg reflector (DBR), and photonic crystal resonators with features as small as 100 nm. photolithographic methods.

Organic semiconductor complementary logic circuits

We report the characteristics of all organic complementary circuits including ring oscillators, registers, and flip-flop circuits. Both simulation and experimental results are discussed. The five-stage ring oscillators have a delay time of 38 /spl mu/s (2.63 kHz oscillation frequency) which is close to simulation results from SPICE with organic transistor parameters.

Distributed feedback lasers produced using soft lithography

Research in microfabrication is important to many areas of science and technology. An emerging set of microlithographic techniques, known as soft lithography, uses elastomeric elements for microcontact printing (μCP), molding, or near field photolithography. We describe the use of two soft lithographic techniques to build DFB lasers with narrow emission linewidths. This demonstrates the suitability of soft lithography for building structures that have (i) feature sizes (∼300 nm) significantly less than 1 μm, and (ii) long-range (∼1 mm) spatial coherence. The lasers use optically pumped gain material deposited on a DFB resonator formed from periodic relief on the surface of a transparent substrate. The required relief was generated on glass and polymer surfaces with μCP and replica molding respectively. μCP produced lines of gold on a glass slide; RIE using the gold as a resist generated periodic relief (600 nm period, 50 nm depth) on the glass surface. Polymer gratings with similar dimensions were formed by curing a polyurethane film against an elastomeric mold. The good performance of the lasers suggest the potential utility of soft lithographic techniques for low-cost fabrication of high-performance optoelectronic devices. Other types of resonators, including distributed Bragg reflector and quasi two-dimensional photonic bandgap based resonators can also be fabricated with the techniques demonstrated here.