Flexible touch sensing unit and method of manufacturing a flexible touch sensing unit
A flexible touch sensing unit may include a substrate including an active touch region and an inactive region surrounding the active touch region, a plurality of first sensing electrodes disposed on the active touch region and extending along a first direction, a plurality of second sensing electrodes disposed on the active touch region and extending along a second direction, and a plurality of sensing lines disposed on the inactive region and electrically connected to the first sensing electrodes and the second sensing electrodes. Each of the sensing lines may include a first metal layer, a first conductive layer disposed on the first metal layer, and a second metal layer disposed on the first conductive layer. Each of the first sensing electrodes may include a third metal layer, and each of the second sensing electrodes may include a fourth metal layer. The first conductive layer may include a self-assembled monolayer.
1. A flexible touch sensing unit, comprising:
a substrate comprising an active touch region and an inactive region surrounding the active touch region;
a plurality of first sensing electrodes disposed on the active touch region and extending along a first direction, at least some of the plurality of first sensing electrodes including at least two layers having conductive material;
a plurality of second sensing electrodes disposed on the active touch region and extending along a second direction, at least some of the plurality of second sensing electrodes including at least two layers having conductive material; and
a plurality of sensing lines disposed on the inactive region and electrically connected to the first sensing electrodes and the second sensing electrodes, at least some of the plurality of sensing lines including at least three layers having conductive material,
the sensing lines each comprising
a first metal layer,
a first conductive layer comprising a self-assembled monolayer disposed on the first metal layer, and
a second metal layer disposed on the first conductive layer, wherein
each of the first sensing electrodes comprises a third metal layer and a second conductive layer comprising the self-assembled monolayer disposed on the third metal layer, and
each of the second sensing electrodes comprises a fourth metal layer and a third conductive layer comprising the self-assembled monolayer disposed on the fourth metal layer.
2. The flexible touch sensing unit of claim 1 , wherein each of the first metal layer, the third metal layer, and the fourth metal layer comprises silver nanowire.
3. The flexible touch sensing unit of claim 1 , wherein the second metal layer comprises aluminum (Al).
4. The flexible touch sensing unit of claim 1 , wherein the self-assembled monolayer comprises at least one of alkanethiol, alkylsilane, and alkyl carboxylate.
5. The flexible touch sensing unit of claim 1 , wherein the self-assembled monolayer comprises at least one of alkanethiol, alkylsilane, and alkyl carboxylate.
6. The flexible touch sensing unit of claim 1 , further comprising an oxidation prevention layer covering the first sensing electrodes, the second sensing electrodes, and the sensing lines.
7. The flexible touch sensing unit of claim 1 , wherein each of the first sensing electrodes comprises a plurality of first sensing cells arranged along the first direction, and each of the second sensing electrodes comprise a plurality of second sensing cells arranged along the second direction.
8. The flexible touch sensing unit of claim 7 , further comprising a bridge connecting adjacent second sensing cells.
9. The flexible touch sensing unit of claim 8 , wherein the bridge comprises at least one of indium tin oxide (ITO) and titanium (Ti).
10. A method of manufacturing a flexible touch sensing unit, comprising:
forming a first metal layer on a substrate;
forming a conductive layer on the first metal layer by using a self-assembled monolayer;
forming a second metal layer on the conductive layer;
patterning the second metal layer; and
patterning the conductive layer and the first metal layer to form first sensing electrodes including at least two layers having conductive material, second sensing electrodes including at least two layers having conductive material, and sensing lines including at least three layers having conductive material, with the sensing lines comprising the first metal layer, the self-assembled monolayer being disposed on the first metal layer and the second metal layer, the first sensing electrodes comprising a third metal layer and the self-assembled monolayer disposed on the third metal layer, and the second sensing electrodes comprising a fourth metal layer and the self-assembled monolayer disposed on the fourth metal layer.
11. The method of claim 10 , wherein the first metal layer is formed by using silver nanowire.
12. The method of claim 10 , wherein the second metal layer is formed by using aluminum (Al).
13. The method of claim 10 , wherein the self-assembled monolayer is formed by using at least one of alkanethiol, alkylsilane, and alkyl carboxylate.
14. The method of claim 10 , wherein the patterning the second metal layer comprises:
forming a photoresist layer on the second metal layer;
forming a photoresist pattern on the second metal layer by using a first mask; and
selectively removing the second metal layer by using the photoresist pattern as an etching mask.
15. The method of claim 14 , wherein the patterning of the conductive layer and the first metal layer comprises:
selectively removing a portion of the conductive layer which is exposed by the
selectively removed second metal layer; and
selectively removing the first metal layer by using a second mask.
16. The method of claim 14 , wherein patterning the conductive layer and the first metal layer comprises selectively removing the conductive layer and the first metal layer by using a third mask.
17. The method of claim 10 , wherein each of the first sensing electrodes comprises a plurality of first sensing cells arranged along a first direction, and each of the second sensing electrodes comprises a plurality of second sensing cells arranged along a second direction crossing the first direction.
18. The method of claim 17 , further comprising forming an insulation layer covering the first sensing cells, the second sensing cells, and the sensing lines.
19. The flexible touch sensing unit of claim 1 , wherein the first conductive layer is configured to serve as an etching mask to prevent etching of the first metal layer.