Solution-processable hole-injection materials with super-deep work functions

9 May 2011. ONDL scientist Rui-Qi PNG announces the successful development of a new generation of super-deep work-function solution-processable hole-injection materials to make ohmic contacts to organic semiconductor devices at the European Materials Research Society meeting today. These polymeric materials have work-functions as large as 5.9 eV. They have been demonstrated to provide unprecedented space-charge-limited hole injection into thin films of organic semiconductor materials with deep ionisation potentials, such as members of the polyfluorene class, which has not been possible previously. Such deep-ionisation-potential materials are important as deep blue emitters, and will likely be increasingly important as air-stable solar cell and transistor materials.

“This breakthrough will ultimately enable more energy-efficient, more stable, and more-robust devices across a wide spectrum of applications, such as lighting, display, solar cells and field-effect transistors, and even for devices based on oxide and chalcogenide semiconductor quantum rods which traditionally suffer from very high ionisation potentials and hence poor hole injection,” says Rui-Qi PNG. The work is done in collaboration with industrial partner Cambridge Display Technology(CDT) and Richard Friend at the University of Cambridge.