Combinatorial methods fabricate libraries of organic light emitters
Scientists at the University of Arizona (Tucson) succeeded in using combinatorial deposition techniques to fabricate libraries of organic light-emitting materials (OLEMs). Masking techniques were used to generate the colorful libraries from only four different organic molecular compounds. Each of the libraries consists of an array of 4-mm-diameter spots that emit different colors when excited with ultraviolet (UV) light. Although combinatorial techniques recently have been used to fabricate libraries of different luminescent inorganic materials, they have not been previously applied to OLEM, according to Ghassan Jabbour, a member of the research team led by Nasser Peyghambarian. The overlap of photoluminescence spectra of the organic materials with their electroluminescent spectra makes the combinatorial approach an exciting and valuable tool in the study of luminescent properties of combinations of organic materials, Jabbour said.
"This technique is also extremely useful in speeding up the screening process of different luminescent dyes used in the fabrication of organic light-emitting devices," he said. "It reveals new dimensions of the dopant-concentration effects on device performance that would have otherwise taken a long time to explore via traditional techniques." Contact Ghassan Jabbour at [email protected].