title: Flexible organic light-emitting diodes with enhanced light out-coupling efficiency fabricated on a double-sided nanotextured substrate.
abstract: High-efficiency organic light-emitting diodes (OLEDs) have generated tremendous research interest. One of the exciting possibilities of OLEDs is the use of flexible plastic substrates, which unfortunately have a mismatching refractive index compared with the conventional ITO anode and the air. To unlock the light loss on flexible plastic, we report a high-efficiency flexible OLED directly fabricated on a double-sided nanotextured polycarbonate substrate by thermal nanoimprint lithography. The template for the nanoimprint process is a replicate from a silica arrayed with nanopillars and fabricated by ICP etching through a SiO2 colloidal spheres mask. It has been shown that with the internal quasi-periodical scattering gratings the efficiency enhancement can reach 50% for a green light OLED, and with an external antireflection structure, the normal transmittance is increased from 89% to 94% for paraboloid-like pillars. The OLED directly fabricated on the double-sided nanotextured polycarbonate substrate has reached an enhancing factor of ∼2.8 for the current efficiency.
authors.affiliation: State Key Laboratory for Manufacturing Systems Engineering, Xi'an Jiaotong University , Xi'an 710049, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Luo
authors.forename: Chunhui
authors.initials: C
authors.lastname: Wang
authors.forename: Li
authors.initials: L
authors.lastname: Wang
authors.forename: Yucheng
authors.initials: Y
authors.lastname: Ding
authors.forename: Long
authors.initials: L
authors.lastname: Li
authors.forename: Bin
authors.initials: B
authors.lastname: Wei
authors.forename: Jianhua
authors.initials: J
authors.lastname: Zhang