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EP-3845962-B1 - DISPLAY PANEL AND DISPLAY DEVICE COMPRISING SAME

EP3845962B1EP 3845962 B1EP3845962 B1EP 3845962B1EP-3845962-B1

Inventors

  • KIM, BYOUNG YONG

Dates

Publication Date
20260513
Application Date
20190708

Claims (6)

  1. A display panel (100) comprising: a display substrate including a display area (DA) and a pad area (PA) disposed around the display area (DA); at least one pad terminal (PE) disposed on the substrate in the pad area (PA); and an open portion (TR) at least partially surrounded by the pad terminal (PE) in a plan view, wherein the open portion (TR) passes through the pad terminal (PE) from a surface of the pad terminal (PE) in a thickness direction, wherein the pad terminal (PE) comprises a first pad electrode (123) and a second pad electrode (144) disposed on the first pad electrode (123) and electrically connected to the first pad electrode (123), wherein the pad terminal (PE) comprises an insulating layer (112) disposed between the first pad electrode (123) and the second pad electrode (144), wherein the insulating layer (112) comprises a plurality of insulating patterns, and the insulating patterns expose an upper surface of the first pad electrode (123), and characterised in that the open portion (TR) passes through the first pad electrode (123), the second pad electrode (144), and the insulating layer (112).
  2. The display panel (100) of claim 1, wherein the second pad electrode (144) covers the plurality of insulating patterns and the exposed upper surface of the first pad electrode.
  3. The display panel (100) of claim 2, wherein the second pad electrode (144) includes surface unevenness by conformally reflecting a lower stepped portion formed by the plurality of insulating patterns.
  4. The display panel (100) of claim 1, wherein the open portion (TR) is disposed inside the pad terminal (PE) and completely surrounded by the pad terminal (PE) in a plan view
  5. The display panel (100) of claim 1, wherein the open portion (TR) has a trench shape that is recessed from one edge of the pad terminal (PE) in a plan view.
  6. The display panel (100) of claim 4, wherein the at least one pad terminal (PE) comprises a first pad terminal and a second pad terminal adjacent to each other, and an open portion of the first pad terminal and an open portion of the second pad terminal face each other.

Description

[Technical Field] The present invention relates to a display panel and a display device including the same. [Background Art] A display device is a device that visually displays data. Such a display device includes a substrate with a display area and a non-display area partitioned from each other. In the display area, a plurality of pixels are disposed on the substrate. In the non-display area, a plurality of pads and the like are disposed on the substrate. A flexible film (chip-on-film (COF) film) on which a driving circuit or the like is mounted is coupled to the plurality of pads to transmit a driving signal to the pixels. The flexible film may include a plurality of leads coupled to the plurality of pads, and each lead may be bonded to a pad separated from one other. The bolding may be achieved through an ultrasonic bonding process, as for example disclosed in US 2017/0365653 A1. A method of testing whether ultrasonic bonding between the pad and the lead is good includes destructive testing and non-destructive testing. The destructive testing is a method of observing a bonding interface between the pad and the lead that are in contact with each other by vertically cutting the pad and the lead. The non-destructive testing is a method of observing the bonding interface using an imaging device or the like without destroying the pad and the lead that are in contact with each other. The non-destructive testing is more advantageous than the destructive testing in that it takes less time to perform the testing. [Disclosure] [Technical Problem] An object of the present invention is directed to providing a display device capable of testing bondability in ultrasonic bonding between a display panel and a flexible printed circuit film. It should be noted that objects of the present invention are not limited to the above-described object, and other objects that are not described herein will be apparent to those skilled in the art from the following descriptions. [Technical Solution] In order to solve the problems, a display panel according to appended claim 1 is provided. The second pad electrode may cover the plurality of insulating patterns and the exposed upper surface of the first pad electrode. The second pad electrode may include surface unevenness by conformally reflecting a lower stepped portion formed by the plurality of insulating patterns. The through-hole may be disposed inside the pad terminal and completely surrounded by the pad terminal in a plan view. The open portion may have a trench shape that is recessed from one edge of the pad terminal in a plan view. The at least one pad terminal may include a first pad terminal and a second pad terminal adjacent to each other, and an open portion of the first pad terminal and an open portion of the second pad terminal may face each other. In order to solve the problems, a display device according to another embodiment includes a display substrate including a display area and a pad area disposed around the display area, a pad terminal disposed on the substrate in the pad area wherein the pad terminal includes a first pad electrode and a second pad electrode disposed on the first pad electrode and electrically connected to the first pad electrode, an open portion at least partially surrounded by the pad terminal, and a circuit board including a lead terminal attached to the pad area and connected to the pad terminal. The lead terminal may include a first area overlapping the open portion of the pad terminal. The lead terminal may include a second area disposed around the first area and configured not to overlap the open portion. The lead terminal may fill at least a portion of the open portion in the first area. A first thickness of the lead terminal in the first area may be greater than a second thickness of the lead terminal in the second area. The lead terminal may be in direct contact with the pad terminal. The lead terminal and the pad terminal may be ultrasonically bonded to each other. The open portion may include a through-hole passing through the first pad electrode and the second pad electrode in a thickness direction. The through-hole may be disposed inside the pad terminal and completely surrounded by the pad terminal in a plan view. Specific details of other exemplary embodiments are included in the detailed description and the accompanying drawings. [Advantageous Effects] A display device according to an embodiment of the present invention includes a through-hole in a pad terminal that is ultrasonically bonded to a lead terminal. The display device may test bondability in ultrasonic bonding between a display panel and a flexible printed circuit film by observing some lead terminals inserted into the through-hole. Advantageous effects of the present invention are not limited to the above description, and various other effects are included in this specification. [Description of Drawings] FIG. 1 is a plan layout view of a display device according to a