Organic electroluminescent device and a method of manufacturing thereof
View Patent ↗An electroluminescent device ( 21 ) comprises a first ( 23 ) and a second ( 26 ) electrode layer, at least the second electrode layer ( 26 ) being provided in accordance with a desired pattern and one or more functional layers ( 24, 25 R, 25 G, 25 B), the one or at least one of said functional layers being an electroluminescent layer. In order to pattern the second electrode layer ( 26 ) the EL device ( 21 ) comprises a relief pattern ( 27 ) having one or more overhanging sections ( 29 ). The EL device has means for hindering the transport of fluid along a capillary channel ( 33 ) formed by an overhanging section ( 29 ) and the surface ( 28 a ) supporting that section, an example of such means being protrusions ( 35 ) which block and/or reroute the capillary channel ( 33 ). Thus the transport of fluid by the channels ( 33 ) during manufacture of the EL device is hindered and color bleeding between pixels of the EL device and/or leakage current among electrodes of the first electrode layer is prevented.
1. An electroluminescent device comprising:
a first and a second electrode layer, at least the second electrode layer being provided in accordance with a desired pattern,
one or more functional layers, the one or at least one of said functional layers being an electroluminescent layer,
a relief pattern having one or more overhanging sections for defining the desired pattern of the second electrode layer,
wherein the device is a matrix display device of the passive type comprising row electrodes as the first electrode layer, column electrodes as the second electrode layer, independently addressable electroluminescent elements formed at crossings of row and column electrodes, and the relief pattern having overhanging sections in the form of strips extending along and between the column electrodes, and
wherein each of the strips include at least one protrusion extending transversely to the boundary of each of the strips and having a free end, wherein the at least one protrusion hinders transport of a fluid along a capillary channel formed by an overhanging section and a surface supporting the overhanging section.
2. An electroluminescent device as claimed in claim 1 wherein the relief pattern has one or more positively-sloped sections.
3. An electroluminescent device as claimed in claim 2 , wherein the relief pattern is a composite relief pattern comprising a first relief pattern having overhanging sections overlaying or underlying a second relief pattern having positively-sloped sections.
4. An electroluminescent device as claimed in claim 3 , wherein the first and second relief pattern are directly supported by a same substrate surface, except where the first and the second relief pattern cross each other.
5. An electroluminescent device as claimed in claim 3 , wherein the second relief pattern provides the supporting surface of the first relief pattern.
6. A battery-operated and/or hand-held electronic device such as a mobile phone, provided with an electroluminescent device as claimed in claim 1 .
7. A battery-operated and/or hand-held electronic device, such as a mobile phone, provided with the electroluminescent device of claim 2 .
8. A battery-operated and/or hand-held electronic device, such as a mobile phone, provided with the electroluminescent device of claim 3 .
9. A battery-operated and/or hand-held electronic device, such as a mobile phone, provided with the electroluminescent device of claim 4 .