Dual Function OLED Transparent Electrode and Light Extraction Layer—Solution
Deposition Systems, Inc., 6780 Cortona Dr STE 150, Goleta, CA 93117-3022
Jacob Richardson, Principal
Investigator, jake@solutiondepositionsystems.com
Jacob Richardson, Business Official,
jake@solutiondepositionsystems.com
Amount: $150,000
Organic light emitting diode
(OLED) based lighting technology currently suffers from low light extraction
efficiency and high production cost. The Department of Energy’s Solid State
Lighting Program under the Office of Energy Efficiency & Renewable Energy
has set aggressive targets for improved efficiency and cost reduction for OLEDs
which will require new materials and manufacturing technologies. Two specific
areas of interest for the Solid State Lighting program, and the associated
research and manufacturing communities, are: 1) new scalable technologies that
efficiently extract light that would otherwise be lost to guided or surface
plasmon modes, and 2) new lower cost, high performance technologies to replace
physical vapor deposited indium tin oxide transparent conductive electrodes. This
project aims to develop a dual function transparent electrode and light
extraction enhancement layer for OLED based solid state lighting. The layer
will simplify and lower the cost of OLED manufacturing by combining light
extraction and transparent electrode functionality, typically requiring two
separate material layers, into a single layer. The dual function layer will be
based on ZnO and will be deposited using a green chemistry, aqueous solution
deposition process. Compared to physical vapor deposition of indium tin oxide,
solution deposited ZnO will provide lower raw material, capital equipment, and
operating costs. The light extraction functionality in the layer will be
enabled by the creation of nano/micro scale porosity within the ZnO crystals.
Depending on their size, density, and other characteristics, the pores may be
used to vary the effective refractive index and or act as light scattering
centers in the ZnO layer, both of which can be used to enhance light
extraction. In Phase I of the project, there will be four major tasks/objectives
to demonstrate technical feasibility: modelling/simulation to identify target
materials properties and device structures and predict their performance,
develop processes for achieving target properties in the ZnO layer, develop a
OLED structure and scalable fabrication process incorporating the ZnO layer,
and demonstrate an OLED incorporating the ZnO layer with at least
2.5 times greater light extraction than a reference OLED design using
indium tin oxide. Solid state lighting technologies like OLEDs have massive
potential to reduce energy consumption due to higher efficiency than older
lighting technologies. Despite the increased adoption of inorganic LED lighting
in recent years, the energy saving potential of solid state lighting still
remains largely untapped. The low glare, low brightness, and large area surface
illumination characteristics of OLED lighting make it more attractive than LED
lighting in certain applications. The successful development of the proposed
technology will accelerate the commercialization and adoption of OLED lighting
by increasing efficiency and lowering costs. As a result, greater energy
savings from solid state lighting will be realized.