TWI613942B - Electrical connection structure - Google Patents

Abstract

An electrical connection structure located at the edge of a flexible display. The electrical connection structure comprises a flexible substrate, a first wiring layer, an organic buffer layer, an organic gate isolation layer and an organic protective layer. The first circuit layer is on the flexible substrate and extends toward the edge of the flexible substrate. The organic buffer layer is located on the flexible substrate and the first circuit layer such that the first circuit layer is located between the organic buffer layer and the flexible substrate. The organic gate isolation layer is on the organic buffer layer. The organic protective layer is on the organic gate isolation layer. The organic protective layer, the organic gate isolation layer and the organic buffer layer together have two perforations such that the first wiring layer portion is located in the perforations.

Description

Electrical connection structure

This case is about an electrical connection structure.

Generally, the edge of the display device is provided with a flexible printed circuit board (FPC), so that the display device can receive signals and power of the external electronic device through the flexible circuit board. Since the conventional display device is not flexible, the flexible circuit board electrically connected to the display device is not easily pulled, and it is not necessary to consider the tensile strength of the flexible circuit board. However, in a display device of an organic thin film OLED array, since it has flexibility, it is necessary to consider the tensile strength of a flexible circuit board.

Generally, the organic thin film transistor array display device sequentially stacks an organic buffer layer, an organic gate isolation layer and an organic protective layer on the edge of the flexible substrate, and is formed between the organic buffer layer and the organic gate isolation layer. Connecting the integrated circuit (IC) and the circuit of the flexible circuit board, and both ends of the line are exposed from the two through holes of the organic gate isolation layer and the organic protection layer, respectively, for the integrated circuit and the flexible circuit board to be bonded to the display A flexible substrate for the device.

However, such an electrical connection structure is in contact with the organic buffer layer because of its wiring, and the organic buffer layer is an organic material, so the adhesion of the wiring is poor. Such as As a result, after the circuit is connected to the flexible circuit board, the line is easily damaged by the tension of the flexible circuit board, for example, the flexible circuit board is difficult to withstand a pulling force greater than 0.5 N/mm.

One aspect of the present invention is an electrical connection structure located at the edge of a flexible display.

According to an embodiment of the invention, an electrical connection structure includes a flexible substrate, a first wiring layer, an organic buffer layer, an organic gate isolation layer, and an organic protective layer. The first circuit layer is on the flexible substrate and extends toward the edge of the flexible substrate. The organic buffer layer is located on the flexible substrate and the first circuit layer such that the first circuit layer is located between the organic buffer layer and the flexible substrate. The organic gate isolation layer is on the organic buffer layer. The organic protective layer is on the organic gate isolation layer. The organic protective layer, the organic gate isolation layer and the organic buffer layer together have two perforations such that the first wiring layer portion is located in the perforations.

In an embodiment of the invention, the electrical connection structure further includes a second circuit layer. The second circuit layer is located on the first circuit layer in the via and extends to the organic buffer layer between the wall surface of the via and the organic buffer layer and the organic gate isolation layer.

In an embodiment of the invention, the second circuit layer extends from the first circuit layer in one of the perforations to the first circuit layer in the other of the perforations.

In an embodiment of the invention, the electrical connection structure further includes a first conductive layer. The first conductive layer is located on the second circuit layer in the through hole such that the second circuit layer is located between the first conductive layer and the first circuit layer.

In an embodiment of the invention, the first conductive layer extends between the organic gate isolation layer and the organic gate isolation layer and the organic gate layer.

In an embodiment of the invention, the first conductive layer extends from the second wiring layer in one of the through holes to the second wiring layer in the other of the through holes.

In an embodiment of the invention, the electrical connection structure further includes a second conductive layer. The second conductive layer is located on the first conductive layer in the through hole such that the first conductive layer is located between the second conductive layer and the second circuit layer.

In an embodiment of the invention, the second conductive layer extends to the surface of the organic protective layer surrounding the organic gate layer on the wall surface of the through hole and the organic protective layer.

In an embodiment of the invention, the flexible substrate has a barrier layer. At least a portion of the barrier layer is covered by the first circuit layer.

In an embodiment of the invention, the organic gate isolation layer is between the organic protective layer and the organic buffer layer.

In an embodiment of the invention, the first circuit layer has a thickness of between 1,500 angstroms and 2,500 angstroms.

In an embodiment of the invention, the material of the first circuit layer comprises aluminum, molybdenum, chromium, titanium, copper, nickel or an alloy thereof.

In an embodiment of the invention, the electrical connection structure further includes an integrated circuit. The integrated circuit is electrically connected to the first circuit layer located in one of the perforations.

In an embodiment of the invention, the electrical connection structure further includes Flexible circuit board. The flexible circuit board electrically connects the first circuit layer in another via.

In the above embodiment of the present invention, since the first wiring layer of the electrical connection structure is on the flexible substrate, not on the organic material, the adhesion of the first wiring layer is improved. In addition, the organic buffer layer, the organic gate isolation layer and the organic protective layer are sequentially stacked on the first circuit layer, and have two perforations in common, and the first circuit layer is located in the through hole. In this way, when the contacts of the integrated circuit and the flexible circuit board are respectively disposed in the through holes, the flexible circuit board can be electrically connected to the integrated circuit through the first circuit layer. Since the adhesion between the first circuit layer and the flexible substrate is good, the tensile strength of the flexible circuit board is improved. When the flexible display pulls the flexible circuit board by bending, the first circuit layer and other metal layers in the through hole can be prevented from being damaged by the pulling force of the flexible circuit board.

100, 100A, 100B, 100C, 100D, 100E‧‧‧ electrical connection structure

110‧‧‧Flexible substrate

112‧‧‧ surface

114‧‧‧Barrier layer

120‧‧‧First line layer

130‧‧‧Organic buffer layer

132‧‧‧ wall

134‧‧‧ wall

136‧‧‧ surface

140‧‧‧Organic gate isolation

142‧‧‧ wall

144‧‧‧ wall

146‧‧‧ surface

150‧‧‧Organic protective layer

152‧‧‧ wall

154‧‧‧ wall

156‧‧‧ surface

162‧‧‧Perforation

164‧‧‧Perforation

170, 170a‧‧‧second circuit layer

180, 180a‧‧‧ first conductive layer

190‧‧‧Second conductive layer

200‧‧‧flexible display

202‧‧‧ display area

210‧‧‧ integrated circuit

220‧‧‧Soft circuit board

2-2‧‧‧ segments

L1, L2‧‧‧ fold line

1 is a top plan view of an electrical connection structure at an edge of a flexible display in accordance with an embodiment of the present invention.

2 is a cross-sectional view of the electrical connection structure of FIG. 1 taken along line 2-2.

3 is a cross-sectional view showing an electrical connection structure according to an embodiment of the present invention.

4 is a cross-sectional view showing an electrical connection structure according to an embodiment of the present invention.

Figure 5 is a cross-sectional view showing an electrical connection structure in accordance with an embodiment of the present invention.

Figure 6 is a diagram showing the tension-time relationship of the electrical connection structure of the flexible circuit board connected to Figure 5 and the connection of the conventional electrical connection structure.

Figure 7 is a cross-sectional view showing an electrical connection structure in accordance with an embodiment of the present invention.

Figure 8 is a cross-sectional view showing an electrical connection structure in accordance with an embodiment of the present invention.

The embodiments of the present invention are disclosed in the following drawings, and the details of However, it should be understood that these practical details are not intended to limit the invention. That is, in some embodiments of the invention, these practical details are not necessary. In addition, some of the conventional structures and elements are shown in the drawings in a simplified schematic manner in order to simplify the drawings.

1 is a top plan view of an electrical connection structure 100 at the edge of a flexible display 200 in accordance with an embodiment of the present invention. 2 is a cross-sectional view of the electrical connection structure 100 of FIG. 1 taken along line 2-2. For the sake of brevity, the integrated circuits 210 and the flexible circuit board 220 of Fig. 1 are omitted in the second to fifth embodiments. Referring also to FIGS. 1 and 2, the flexible display 200 has a display area 202. The electrical connection structure 100 is located at the edge of the flexible display 200, for example, the electrical connection structure 100 is located outside of the display area 202. The electrical connection structure 100 includes a flexible substrate 110, a first wiring layer 120, an organic buffer layer 130, an organic gate isolation layer 140 (OGI), and an organic protective layer 150 (Organic Passivation; OPV).

The first circuit layer 120 is located on the surface 112 of the flexible substrate 110, and the first circuit layer 120 extends toward the edge of the flexible substrate 110. The organic buffer layer 130 is located on the flexible substrate 110 and the first wiring layer 120 such that the first wiring layer 120 is located between the organic buffer layer 130 and the flexible substrate 110. The organic gate isolation layer 140 is on the organic buffer layer 130. The organic protective layer 150 is on the organic gate isolation layer 140. That is, the organic gate isolation layer 140 is located between the organic protective layer 150 and the organic buffer layer 130.

In addition, the organic protective layer 150, the organic gate isolation layer 140 and the organic buffer layer 130 have two vias 162, 164 together such that the first wiring layer 120 is partially located in the vias 162, 164. In the present embodiment, the first circuit layer 120 is exposed from the vias 162, 164, and the first circuit layer 120 in the vias 162 can be electrically connected to the integrated circuit 210, and the first circuit layer 120 in the vias 164 can be used to make an incoming call. The flexible circuit board 220 is connected.

Since the first wiring layer 120 of the electrical connection structure 100 is located on the flexible substrate 110, not on the organic material, the adhesion of the first wiring layer 120 is improved. In addition, the organic buffer layer 130, the organic gate isolation layer 140 and the organic protection layer 150 are sequentially stacked on the first circuit layer 120, and the first circuit layer 120 is located in the vias 162, 164. In this way, when the contacts of the integrated circuit 210 and the flexible circuit board 220 are respectively disposed in the through holes 162 and 164, the flexible circuit board 220 can be electrically connected to the integrated circuit 210 through the first circuit layer 120, so that the signal is in the The flexible circuit board 220 is transferred between the integrated circuit 210 and the integrated circuit 210.

In addition, since the adhesion between the first circuit layer 120 and the flexible substrate 110 is good, the tensile strength of the flexible circuit board 220 is improved. When the flexible display 200 pulls the flexible circuit board 220 due to bending, the first line can be avoided The layer 120 and other conductive metal layers in the vias 162, 164 (which will be described later) are damaged by the pulling force of the flexible circuit board 220, for example, the first wiring layer 120 can be prevented from being detached from the flexible substrate 110.

In this embodiment, the material of the flexible substrate 110 may include germanium, and the material of the first circuit layer 120 may include aluminum, molybdenum, chromium, titanium, copper, nickel or an alloy thereof to make the first circuit layer 120 and the flexible The substrate 110 has good adhesion between the substrates. In addition, the thickness of the first wiring layer 120 may be between 1500 angstroms and 2,500 angstroms to allow the first wiring layer 120 to have good strength so that it is not easily broken when bent or when the flexible circuit board 220 is pulled.

In addition, the flexible substrate 110 has a barrier layer 114 covering the surface 112 (eg, germanium nitride, SiNx), and at least a portion of the barrier layer 114 (eg, the barrier layer 114 located at the edge of the flexible substrate 110) is first The circuit layer 120 is covered. The barrier layer 114 can be used to prevent intrusion of water and gas to extend the useful life of the flexible display 200.

It should be understood that the component connection relationships and materials that have been described will not be repeated, and will be described first. In the following description, other types of electrical connection structures will be described.

3 is a cross-sectional view of an electrical connection structure 100A in accordance with an embodiment of the present invention. Referring to FIGS. 1 and 3 , the electrical connection structure 100A includes a flexible substrate 110 , a first wiring layer 120 , an organic buffer layer 130 , an organic gate isolation layer 140 , and an organic protective layer 150 . The difference from the embodiment of FIG. 2 is that the electrical connection structure 100A further includes the second wiring layer 170. The second circuit layer 170 is located on the first circuit layer 120 of the vias 162, 164. The second wiring layer 170 extends to the organic buffer layer 130 around the wall surface 132 of the via 162 and organic buffer Layer 130 surrounds wall 134 of perforation 164. Further, the second wiring layer 170 extends between the organic buffer layer 130 and the organic gate isolation layer 140. In the present embodiment, the second wiring layer 170 extends from the first wiring layer 120 of the via 162 to the first wiring layer 120 of the other via 164 such that the second wiring layer 170 covers the between the vias 162, 164. Organic buffer layer 130 surface 136.

When the contacts of the integrated circuit 210 and the flexible circuit board 220 are respectively disposed in the through holes 162 and 164, the flexible circuit board 220 can be electrically connected to the integrated circuit 210 through the first circuit layer 120 and the second circuit layer 170. The signal is transmitted between the flexible circuit board 220 and the integrated circuit 210. With such a design, when either of the first circuit layer 120 and the second circuit layer 170 is damaged, the integrated circuit 210 and the flexible circuit board 220 can still be turned on. That is, both the first circuit layer 120 and the second circuit layer 170 can electrically connect the integrated circuit 210 and the flexible circuit board 220 as the electrical connection structure 100A.

In the present embodiment, since the second circuit layer 170 is not the first layer on the flexible substrate 110, the thickness of the second circuit layer 170 may be smaller than the thickness of the first circuit layer 120 to save material cost, but it is not used. To limit the invention.

4 is a cross-sectional view of an electrical connection structure 100B in accordance with an embodiment of the present invention. Referring to FIGS. 1 and 4 , the electrical connection structure 100B includes a flexible substrate 110 , a first wiring layer 120 , an organic buffer layer 130 , an organic gate isolation layer 140 , an organic protective layer 150 , and a second wiring layer 170 . The difference from the embodiment of FIG. 3 is that the electrical connection structure 100B further includes the first conductive layer 180. The first conductive layer 180 is located on the second circuit layer 170 of the vias 162, 164 such that the second circuit layer 170 is located at the first conductive layer 180 and the first circuit layer 120. between. In addition, the first conductive layer 180 extends over the wall surface 142 of the via 162 around the via 142 of the organic gate isolation layer 140 and the organic gate isolation layer 140. In the present embodiment, the first conductive layer 180 also extends between the organic gate isolation layer 140 and the organic protective layer 150, that is, to the surface 146 of the organic gate isolation layer 140.

When the contacts of the integrated circuit 210 and the flexible circuit board 220 are respectively disposed in the through holes 162 and 164, the first conductive layer 180 can serve as a bonding pad, so that the integrated circuit 210 and the flexible circuit board 220 can be respectively separated. The first circuit layer 120 and the second circuit layer 170 are electrically connected through the first conductive layer 180 of the vias 162, 164.

FIG. 5 is a cross-sectional view showing an electrical connection structure 100C according to an embodiment of the present invention. Referring to FIGS. 1 and 5 , the electrical connection structure 100C includes a flexible substrate 110 , a first wiring layer 120 , an organic buffer layer 130 , an organic gate isolation layer 140 , an organic protective layer 150 , and a second wiring layer 170 . A conductive layer 180. The difference from the embodiment of FIG. 4 is that the electrical connection structure 100C further includes the second conductive layer 190. The second conductive layer 190 is located on the first conductive layer 180 in the vias 162, 164 such that the first conductive layer 180 is located between the second conductive layer 190 and the second wiring layer 170. In addition, the second conductive layer 190 extends over the wall surface 152 of the organic protective layer 150 around the perforations 162 and the wall 154 surrounding the perforations 164 with the organic protective layer 150. In the present embodiment, the second conductive layer 190 also extends to the surface 156 of the organic protective layer 150 facing away from the organic gate isolation layer 140.

When the contacts of the integrated circuit 210 and the flexible circuit board 220 are respectively disposed in the through holes 162 and 164, the second conductive layer 190 can serve as a bonding pad, so that the integrated circuit 210 and the flexible circuit board 220 can be respectively separated. Through The first conductive layer 180 and the second conductive layer 190 of the vias 162 and 164 are electrically connected to the first circuit layer 120 and the second circuit layer 170.

FIG. 6 is a diagram showing the tension-time relationship between the flexible circuit board connecting the electrical connection structure 100C of FIG. 5 and the conventional electrical connection structure. Referring to FIG. 5 and FIG. 6 simultaneously, when the contact of the flexible circuit board is disposed on the second conductive layer 190 in the through hole 164 of FIG. 5, the flexible circuit board can withstand about 3 N/mm in the electrical connection structure 100C. The tensile force (for example, 3.05 N/mm, that is, the maximum value of the fold line L1) is significantly larger than the tensile force that the flexible circuit board can withstand in the conventional electrical connection structure (for example, 0.56 N/mm, that is, the maximum value of the fold line L2), but The above data is not intended to limit the invention.

FIG. 7 is a cross-sectional view showing an electrical connection structure 100D according to an embodiment of the present invention. The electrical connection structure 100D includes a flexible substrate 110, a first wiring layer 120, an organic buffer layer 130, an organic gate isolation layer 140, an organic protection layer 150, a second wiring layer 170a, a first conductive layer 180, and a second conductive layer 190. . The difference from the embodiment of FIG. 5 is that the second circuit layer 170a does not extend from the first circuit layer 120 of the through hole 162 to the first circuit layer 120 in the other through hole 164, but is divided into two parts. At least a portion of the organic gate isolation layer 140 can be positioned between the two portions of the second wiring layer 170a.

FIG. 8 is a cross-sectional view showing an electrical connection structure 100E according to an embodiment of the present invention. The electrical connection structure 100E includes a flexible substrate 110, a first wiring layer 120, an organic buffer layer 130, an organic gate isolation layer 140, an organic protection layer 150, a second wiring layer 170, a first conductive layer 180a and a second conductive layer 190. . The difference from the embodiment of FIG. 5 is that the first conductive layer 180a extends from the second wiring layer 170 in the through hole 162 to the second line in the other through hole 164. On layer 170.

Referring to FIG. 1 and FIG. 8 , when the contacts of the integrated circuit 210 and the flexible circuit board 220 are respectively disposed in the through holes 162 and 164 , the flexible circuit board 220 can pass through the first circuit layer 120 and the second circuit layer 170 . The first conductive layer 180a is electrically connected to the integrated circuit 210 to transmit signals between the flexible circuit board 220 and the integrated circuit 210. With such a design, even if either or both of the first wiring layer 120, the second wiring layer 170, and the first conductive layer 180a are damaged, the integrated circuit 210 and the flexible circuit board 220 can be turned on.

Although the present invention has been disclosed in the above embodiments, it is not intended to limit the present invention, and the present invention can be modified and modified without departing from the spirit and scope of the present invention. The scope is subject to the definition of the scope of the patent application attached.

100C‧‧‧Electrical connection structure

110‧‧‧Flexible substrate

114‧‧‧Barrier layer

120‧‧‧First line layer

130‧‧‧Organic buffer layer

132‧‧‧ wall

134‧‧‧ wall

140‧‧‧Organic gate isolation

142‧‧‧ wall

144‧‧‧ wall

150‧‧‧Organic protective layer

152‧‧‧ wall

154‧‧‧ wall

156‧‧‧ surface

162‧‧‧Perforation

164‧‧‧Perforation

170‧‧‧Second circuit layer

180‧‧‧First conductive layer

190‧‧‧Second conductive layer

Claims (13)

An electrical connection structure is disposed at an edge of a flexible display, the electrical connection structure includes: a flexible substrate; a first circuit layer on the flexible substrate and extending toward an edge of the flexible substrate; an organic buffer layer On the flexible substrate and the first circuit layer, such that the first circuit layer is located between the organic buffer layer and the flexible substrate; an organic gate isolation layer is located on the organic buffer layer; an organic protection a layer on the organic gate isolation layer, wherein the organic protection layer, the organic gate isolation layer and the organic buffer layer have two perforations, such that the first circuit layer portion is located in the perforations; and a second A circuit layer is disposed on the first circuit layer of the vias and extends to the organic buffer layer between the sidewalls of the vias and the organic buffer layer and the organic gate isolation layer. The electrical connection structure of claim 1, wherein the second circuit layer extends from the first circuit layer of one of the vias to the first circuit layer of the other of the vias. The electrical connection structure of claim 1, further comprising: a first conductive layer on the second circuit layer of the plurality of vias, the second circuit layer being located on the first conductive layer and the first line Between the layers. The electrical connection structure of claim 3, wherein the first The conductive layer extends between the organic gate isolation layer and the organic gate isolation layer and the organic protective layer. The electrical connection structure of claim 3, wherein the first conductive layer extends from the second circuit layer of one of the vias to the second circuit layer of the other of the vias. The electrical connection structure of claim 3, further comprising: a second conductive layer on the first conductive layer in the plurality of through holes, the first conductive layer being located on the second conductive layer and the second line Between the layers. The electrical connection structure of claim 6, wherein the second conductive layer extends to the surface of the organic protective layer surrounding the organic gate layer and the organic protective layer surrounding the organic gate layer. The electrical connection structure of claim 1, wherein the flexible substrate has a barrier layer, and at least a portion of the barrier layer is covered by the first circuit layer. The electrical connection structure of claim 1, wherein the organic gate isolation layer is between the organic protective layer and the organic buffer layer. The electrical connection structure of claim 1, wherein the first circuit layer has a thickness of between 1500 angstroms and 2,500 angstroms. The electrical connection structure of claim 1, wherein the material of the first circuit layer comprises aluminum, molybdenum, chromium, titanium, copper, nickel or an alloy thereof. The electrical connection structure of claim 1, further comprising: an integrated circuit electrically connecting the first circuit layer in one of the through holes. The electrical connection structure of claim 12, further comprising: a flexible circuit board electrically connected to the first circuit layer located in the other of the through holes.