Nucleation-Inhibiting Coating for Selective Electrode Deposition
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing opto-electronic device manufacturing processes face challenges in achieving selective deposition of conductive coatings without damaging sensitive organic semiconductor layers, particularly due to high kinetic energy in sputtering processes and high evaporation temperatures, which lead to degradation and increased costs with multi-layered electrodes and complex mask usage.
Innovation Solution
An opto-electronic device with a second electrode comprising ytterbium (Yb) and magnesium (Mg), where the second electrode has a lower section proximate to the semiconducting layer and an upper section with a Yb-containing Mg alloy, utilizing a nucleation-inhibiting coating (NIC) to inhibit conductive coating deposition in transmissive regions, allowing for selective and efficient conductive coating patterning.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If sputtering process is used to deposit conductive coating, then light transmission is improved, but organic semiconductor layers become damaged due to high kinetic energy of sputtered atoms
Solution Approach 1:
The patent introduces a nucleation-inhibiting coating (NIC) as an intermediary layer between the organic semiconductor layer and the conductive coating. This NIC layer has low initial sticking probability for conductive coating materials, preventing direct deposition on the sensitive organic layer while still allowing the beneficial low-temperature deposition process to proceed. The NIC acts as a protective mediator that eliminates the harmful interaction between sputtered atoms and the organic semiconductor.
2Reliability
If thermal evaporation at high temperatures is used to deposit metallic materials, then conductive coating is achieved, but substrate and organic semiconductor layers are degraded due to high temperatures
Solution Approach 1:
The nucleation-inhibiting coating serves as a thermal buffer and protective intermediary that enables low-temperature deposition processes. By preventing direct contact between the organic semiconductor layer and the deposition process, the NIC allows conductive coatings to be formed without subjecting the temperature-sensitive organic layers to high thermal loads, thus maintaining material integrity while achieving electrical conductivity.
3Illumination intensity
If multi-layered electrode structure is used, then trade-off between light transmission and resistivity is improved, but manufacturing cost and complexity increase due to multiple deposition steps
Solution Approach 1:
The patent combines the nucleation-inhibiting coating and the conductive coating into a single integrated deposition step. The NIC is deposited first to pattern the transmissive regions, and then the conductive coating material is deposited in the same vacuum cycle without breaking the vacuum or requiring additional processing steps. This merging of functions into one process reduces manufacturing complexity while achieving both light transmission and electrical conductivity requirements.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This solution enables the selective deposition of conductive coatings while minimizing damage to organic semiconductor layers, reducing costs and complexity, and improving the trade-off between light transmission and resistivity, thus enhancing the manufacturing process efficiency and yield.
Implementation Method 1
One method for doing so, especially when the electrode is a light transmissive electrode, involves depositing, by a sputtering process, materials typically used to form the transmissive electrode
Implementation Method 2
However, the use of materials such as Ag and/or Al specify such materials to be deposited by thermal evaporation at high temperatures in excess of 1000° C.
Data Source
AI summary
An opto-electronic device comprises first and second electrodes and a semiconducting layer therebetween. The second electrode comprises ytterbium and magnesium. The second electrode may comprise a fullerene. The second electrode may comprise a lower section comprising ytterbium and/or fullerene and an upper section comprising a ytterbium-containing magnesium alloy. The lower section may comprise an interface section in physical contact with the semiconducting layer. The interface section may comprise ytterbium fulleride. In some examples, an interface coating comprising ytterbium extends across a pixel region and a transmissive region. A nucleation inhibiting coating (NIC) is disposed over the interface coating in the transmissive region. A conductive coating is disposed over the interface coating in the pixel region. The NIC surface in the transmissive region is substantially devoid of a closed coating film of the conductive coating. The interface coating may comprise fullerene. The conductive coating may be a ytterbium-containing magnesium alloy.