Improved Process for Fabrication of Bi-layer​ Polymer-Based Organic Light Emitting Diodes (OLEDs)

The development of a light emitting diode (LED) device using organic polymers (OLED) has generated significant interest in the scientific and engineering communities over the past two decades due to the potential of the wide variety of organic compounds that can be used for engineering desired optical and mechanical properties. The current work is based on results from work done be a former TLU physics student to find optimal process protocols for producing repeatable and reliable device performance and minimizing material costs. For this experiment, the spin-coating method for deposition of the polymer bi-layers served as the primary variable to determine impact on device characteristics and performance. Additionally, the work aimed to develop an improved characterization method to acquire light emission during current- voltage characterization using an integrated routine in LabVIEW^TM software, which was used to ascertain device properties. A total of 13 individual devices were constructed using Indium-Tin-Oxide coated glass slides and a bi-layer of organic polymers, MEHPPV and PEDOT-PSS. Gallium-Indium eutectic was used to form the cathode and the sandwich-like devices were secured using optical adhesive. Results revealed that samples prepared using slightly slower spin speeds for the PEDOT-PSS layer exhibited the best performance for both light emission and current density.