KR-20260063093-A - PAD CONNECTION STRUCTURE AND TRANSPARENT DISPLAY DEVICE

KR20260063093AKR 20260063093 AKR20260063093 AKR 20260063093AKR-20260063093-A

Abstract

A pad connection structure and a transparent display device including the same are provided. The pad connection structure includes a pad element comprising a base substrate and pads arranged on the base substrate, a circuit board disposed on the pads and comprising a wiring layer, a conductive structure electrically connecting the wiring layer and the pads, and a bonding structure including a trench with one end open that attaches the circuit board to the pad element.

Inventors

이철훈
이찬희
김원섭

Assignees

동우 화인켐 주식회사

Dates

Publication Date: 20260507
Application Date: 20241030

Claims (18)

A pad element comprising a base substrate and pads arranged on the base substrate; A circuit board disposed on the above pads and comprising a wiring layer; A conductive structure that electrically connects the wiring layer and the pads; and A pad connection structure comprising a circuit board attached to the pad element and a bonding structure including a trench with one end open.
A pad connection structure according to claim 1, wherein the other end, which is opposite to the one end of the trench, is closed.
A pad connection structure according to claim 2, wherein the pads are exposed from the bonding structure through the trench.
A pad connection structure according to claim 3, wherein the pads are arranged in a second direction parallel to the upper surface of the base substrate to define a pad row, and a plurality of pad rows are arranged along a first direction parallel to the base substrate and intersecting the second direction.
In claim 4, the trench is formed corresponding to each of the pad rows, and The above joint structure comprises a pad connection structure including a blocking portion that separates the trenches, and a merging portion that closes the other ends of the trenches and connects the blocking portions.
A pad connection structure according to claim 1, wherein one end portion of the trench has a reduced width.
A pad connection structure according to claim 1, wherein one end portion of the trench has an extended width.
A pad connection structure according to claim 1, wherein one end of the circuit board does not overlap with one end of the bonding structure, and an opening is formed between the one end of the circuit board and the pad element that communicates with the open one end of the trench.
In claim 1, the circuit board is Core layer; A first wiring layer disposed on the upper surface of the core layer; A second wiring layer disposed on the bottom surface of the core layer; A through hole penetrating the core layer; and A pad connection structure comprising a wiring connection portion formed on the side wall of the through hole and connecting the first wiring layer and the second wiring layer.
In claim 9, the conductive structure is a pad connecting structure that extends from the upper surface of each of the pads and is inserted into the through hole.
In claim 10, the conductive structure is a pad connection structure that contacts the wiring connection portion within the through hole.
In claim 10, the conductive structure comprises a pad connection structure including a solder pillar.
In claim 1, the pad element further comprises circuit wiring connected to each of the pads, and A pad connection structure in which one end of the above trench is open toward the extension direction of the signal wiring from the pads.
A pad connection structure according to claim 1, wherein the pads each comprise a metal pattern and a capping layer formed on the surface of the metal pattern.
Pad connection structure of claim 1; Circuit wiring connected to the pads of the pad connection structure; and A transparent display device comprising light-emitting elements arranged on the base substrate and electrically connected to the circuit wiring.
In claim 15, the base substrate comprises a pad region where the pads are arranged and a device region where the light-emitting elements are arranged, and A transparent display device in which one end of the trench of the pad connection structure is open toward the element area.
In claim 15, further comprising a conductive intermediate structure connecting the circuit wiring and the light-emitting elements, A transparent display device in which the above conductive mediating structure comprises the same material as the above conductive structure.
In claim 15, the circuit wiring comprises a first driving wiring and a second driving wiring spaced apart from each other in parallel, and A transparent display device in which the light-emitting elements are arranged between the first driving wire and the second driving wire to form a row of light-emitting elements.

Description

Pad connection structure and transparent display device including the same The present invention relates to a pad connection structure and a transparent display device including the same. More specifically, the invention relates to a pad connection structure including a circuit board and pads, and a transparent display device including the same. For example, it is applied to Light Emitting Diode (LED) display panels and is widely utilized in the fields of advertising videos and media art. As an eco-friendly component, LEDs provide high response speed and high-brightness color reproduction. Furthermore, brightness and color temperature can be controlled by adjusting the light output of red, green, and blue LEDs, and display devices can be manufactured in a compact size by assembling multiple LEDs into a single module or panel. A transparent display device may include a transparent substrate and a plurality of LED elements arranged on the transparent substrate. Circuit wiring for driving the plurality of LED elements is arranged on the transparent substrate. Connections between pads and circuit boards may be performed to supply signals to the above circuit wirings. The connection of the circuit board may involve high-temperature heat treatment, which may result in damage to structures due to heat and gas generation. In this case, mechanical and electrical defects may occur due to poor bonding of the circuit board, and the electrical signal characteristics to the circuit wirings and LED elements may also be degraded. For example, Korean registered patent publication No. 10-2590822 discloses an LED module including a transparent molding. FIGS. 1 and FIGS. 2 are a schematic plan view and a cross-sectional view, respectively, showing a pad connection structure according to exemplary embodiments. FIGS. 3 to 5 are schematic partial enlarged plan views showing pad connection structures according to some embodiments. FIG. 6 is a schematic plan view showing a transparent display device according to exemplary embodiments. FIG. 7 is a schematic partial enlarged plan view showing a circuit arrangement around a pixel according to exemplary embodiments. FIG. 8 is a schematic cross-sectional view showing a transparent display device according to exemplary embodiments. Embodiments of the present invention provide a pad connection structure comprising a pad, a circuit board, and a solder structure. Embodiments of the present invention provide a transparent display device comprising the pad connection structure. Embodiments of the present invention will be described in more detail below with reference to the drawings. However, the following drawings attached to this specification are intended to illustrate preferred embodiments of the present invention and serve to further enhance understanding of the technical concept of the present invention together with the aforementioned description; therefore, the present invention should not be interpreted as being limited only to the matters described in such drawings. The terms used in this application, such as "first," "second," "upper," "lower," "upper surface," and "lower surface," do not specify absolute positions but are used to distinguish different configurations or to differentiate relative positions between configurations. The sizes of the configurations/structures depicted in the attached drawings may be exaggerated for convenience of explanation and are not limited to the sizes depicted in the drawings. In the drawings below, the first direction and the second direction may refer to two directions that are parallel to the upper surface of the base substrate (100) and perpendicular to each other. For example, the first direction and the second direction may be the width direction and the length direction of the pad connection structure or the transparent display device, respectively. The third direction may refer to a direction that is perpendicular to the upper surface of the base substrate (100) and perpendicular to the first direction and the second direction. The third direction may be the thickness direction of the pad connection structure or the transparent display device. FIGS. 1 and FIGS. 2 are a schematic plan view and a cross-sectional view, respectively, illustrating a pad connection structure according to exemplary embodiments. Specifically, FIGS. 2 is a cross-sectional view taken in the third direction along the line I-I' of FIGS. 1. Referring to FIGS. 1 and 2, the pad connection structure may include a base substrate (100), a pad (130), a bonding structure (AL), and a circuit board (PCB). The base substrate (100) may be a support substrate on which pads (130) are formed. As described below, the base substrate (100) may be provided as a support substrate on which light-emitting elements are arranged together with the pads (130). The base substrate (100) is a polyester resin such as polyethylene terephthalate, polyethylene isophthalate, polyethylene naphthalate,