Transparent body for a touch panel manufacturing method and system for manufacturing a transparent body for a touch screen panel
A process for manufacturing a transparent body for a touch screen panel is described. The process includes: depositing a first transparent layer stack over a flexible transparent substrate, wherein said first transparent layer stack includes at least a first dielectric film with a first refractive index, and a second dielectric film with a second refractive index different from the first refractive index; providing a transparent conductive film over the first transparent layer stack; depositing a layer of a conductive material over the transparent conductive film; providing a polymer layer over the layer of a conductive material; imprinting a pattern, e.g. a 3D pattern, on the polymer layer; etching the layer of the conductive material based upon the pattern to form conductive paths for the touch screen panel; and etching the transparent conductive film based upon the pattern to form a structured transparent conductive pattern for touch detection.
1. A process for manufacturing a transparent body for a touch screen panel, the process comprising:
using a roll-to-roll system including an unwinding module, a winding module, and a processing module to:
deposit a first transparent layer stack over a flexible transparent substrate, wherein said first transparent layer stack includes at least a first dielectric film with a first refractive index of at least 1.8, and a second dielectric film with a second refractive index of 1.5 or below;
sputter deposit a transparent conductive film over the first transparent layer stack; and
sputter deposit a layer of a conductive material over the transparent conductive film; and
transferring the flexible transparent substrate from the roll-to-roll system to a roll-to-roll imprint station to:
provide a polymer layer over the layer of a conductive material;
imprint a multi-level pattern into the polymer layer with a stamp;
etch the layer of the conductive material exposed by the multi-level pattern to form conductive paths for the touch screen panel; and
etch the transparent conductive film based upon the multi-level pattern to form a structured transparent conductive pattern for touch detection.
2. The process according to claim 1 , wherein the multi-level pattern is a 3D pattern or a first topography having more than one level of depths of an imprint.
3. The process according to claim 1 , further comprising:
depositing a second transparent layer stack over the structured transparent conductive pattern, wherein said second transparent layer stack is selected from the group consisting of:
a layer stack, wherein the layer stack includes a third dielectric film with a gradient refractive index from a third refractive index to a fourth refractive index different from the third refractive index, and
a layer stack, wherein the layer stack includes at least a third dielectric film with a third refractive index and a fourth dielectric film or a transparent adhesive, respectively with a fourth refractive index different from the third refractive index, providing a further photoresist over the second transparent layer stack;
imprinting a further pattern, on the further photoresist; and
etching the second transparent layer stack based upon the further pattern to uncover the conductive paths.
4. The process according to claim 3 , wherein the further pattern is a further 3D pattern or a second topography having one or more levels of depths of an imprint.
5. The process according to claim 1 , wherein at least one of the first dielectric film, the second dielectric film or the transparent conductive film is deposited by sputtering of a target.
6. The process according to claim 1 , wherein the first dielectric film has a refractive index of at least 1.8 and the second dielectric film has a refractive index of 1.5 or below.
7. The process according to claim 3 , wherein the first transparent layer stack and the second transparent layer stack are index matching layer stacks and/or are selected from the group consisting of: SiO x , SiN x , SiO x N y , AlO x , AlO x N y , TiO x , TaOx, MgFx, and NbO.
8. The process according to claim 1 , wherein the dielectric films are sputtered by medium frequency (MF) sputtering, and the transparent conductive films are sputtered by direct current (DC) sputtering.
9. The process according to claim 1 , wherein the transparent conductive film includes indium tin oxide (ITO).
10. The process according to claim 1 , wherein the layer of conductive material includes at least 50 weight-% Cu, Ag, Al, AlNd, Mo, or MoNb.
11. The process according to claim 1 , wherein the flexible transparent substrate is a plastic film.
12. The process according to claim 1 , wherein the flexible transparent substrate is a polyethylene terephthalate (PET) film, a cyclic-olefin-copolymer (COC) film, a triacetate (TAC) film, a cycloolefin polymer (COP) film, or a polyethylene naphthalate (PEN) film.
13. The process according to claim 11 , wherein the plastic film is hard coated.
14. The process according to claim 1 , further comprising:
providing a second flexible film to cover the transparent body.
15. The process according to claim 5 , wherein at least one of the first dielectric film, the second dielectric film or the transparent conductive film is deposited by sputtering of a rotary target.
16. The process according to claim 3 , wherein the third dielectric film has a refractive index of at least 1.8 and the fourth dielectric film has a refractive index of 1.5 or below.
17. The process according to claim 8 , wherein the dielectric films are sputtered by medium frequency (MF) sputtering from a rotatable target, and the transparent conductive films are sputtered by direct current (DC) sputtering from a rotatable target.