The improvement in Quantum Dots (QD)-LED performance through improved polymer hole-injection layer (HIL)/hole-transport layer (HTL) structure and thermal annealing of the QD layer before the deposition of organic electron-transport layer was described. The polymer films were annealed for 15 minutes at different temperatures and the device was fabricated by evaporating electron-transporting small molecule to act as a cathode. The results show that the optimum annealing temperatures for the QD-LEDs correspond to 180°C and show improved spectral purity and enhanced enhanced efficiency after annealing. The decreased turn on voltage results from an increase in the current voltage showing that electrical transport through the polymer film is improved by annealing. Ligand desorption is found to improve charge injection and energy transfer from the organic semiconductors to the QDs by decreasing the thickness of the insulating surfactant shell surrounding each QD.
ASJC Scopus subject areas
- Materials Science(all)