DRIVING CHIP AND METHOD OF MANUFACTURING THE SAME

A driving chip and a method of manufacturing the driving chip are disclosed. In one aspect, the method includes forming an inside metal portion of a connection terminal on a base element by patterning a first metal layer; forming a first insulating layer on the inside metal portion of the connection terminal; forming an inside metal portion of a dummy terminal on the first insulating layer by patterning a second metal layer; and forming a bump portion on the inside metal portion of the connection terminal and on a second metal portion of the dummy terminal. The driving chip may suppress warp transformation or pressure mark of the driving chip and thus, the reliability of the driving chip may be improved.

DETAILED DESCRIPTION

Certain embodiments of a driving chip and a method of manufacturing a driving chip will now be described more fully with reference to the accompanying drawings. It will be understood that when an element such as a layer, film, region, or substrate is referred to as being “on” or “over” another element, it can be directly on the other element or intervening elements may also be present. Similarly, when an element is referred to as being “under” another element, it can be directly under the other element, or intervening elements may also be present.

FIG. 1is a diagram illustrating, illustrating an unmounted driving chip100configured to couple to a pad portion210of a panel200of a flat panel display device, andFIG. 2is a cross-sectional view taken along line II-II ofFIG. 1.

As illustrated inFIG. 1, the panel200includes the pad portion210that is connected to internal components (not shown), and the driving chip100is connected to the pad portion210and, thus, is electrically connected to the internal components.

Connection terminals110that are configured to be coupled to the pad portion210, are disposed along the edge or perimeter of the driving chip100. In the area of the driving chip100between the connection terminals110, or, in the central portion of the driving chip100, electrically isolated dummy terminals120are formed in a line which runs in a direction corresponding to the long side of the driving chip100. The dummy terminals120support the central portion of the driving chip100, thereby preventing warping of the driving chip100. The dummy terminals120also support the connection terminals110, which provide electrical connection with the components. Accordingly, the dummy terminals120do not provide an electrical connection, and prevent warping of the driving chip100. Because the dummy terminals120are disposed between the connection terminals110in a central portion of the driving chip100, the dummy terminals120thus provide support and counteract the external force applied during chip mounting. Therefore warp transformations are unlikely to occur when pressing the driving chip100to mount it on the pad portion210of the panel200, and a pressure mark on the driving chip100due to a warp of the panel200also is unlikely to occur.FIG. 2depicts a cross-sectional structure of the driving chip100that includes the connection terminals110and the dummy terminals120.

As illustrated inFIG. 2, the connection terminals110and the dummy terminals120are formed on a base element100a. Each of the connection terminals110includes an inside metal portion111formed of an aluminum material, and a bump portion112formed of a gold material, which is connected to the inside metal portion111and thus is connected to the pad portion210. Similarly, each of the dummy terminals120includes an inside metal portion121formed of an aluminum material. Also, each of the dummy terminals120includes a bump portion112formed of a gold material. However, unlike the connection terminals110, the dummy terminals120are connected to a second metal portion122. The connection terminals110are connected to a circuit portion (not shown) which is disposed in the base element100a,through the inside metal portion111. However, the dummy terminals120are not electrically connected to the circuit portion because the second metal portion122is not connected to any surrounding element and is isolated from surrounding elements. That is, an insulating gap exists between second metal portion122and inside metal portion121. The inside metal portion121is formed in the same layer as the inside metal portion111of the connection terminals110. The inside metal portion121is formed under the second metal portion122of the dummy terminals120. However, unlike the connection terminals110, the inside metal portion121is separated from the second metal portion122of the dummy terminals120by a first insulating layer131. Thus, the dummy terminals120are electrically isolated from surrounding elements.

FIGS. 3A through 3Lillustrate a method for manufacturing the driving chip100.

First, a first metal layer111ais formed on the base element100aas illustrated inFIG. 3A, and the inside metal portions111of the connection terminals110are formed, as illustrated inFIG. 3B, by patterning the first metal layer111awith a first mask (hereinafter, referred to as a base mask). Here, as described above, the inside metal portion121may be formed in also an area in which the dummy terminal120is to be located. However, the inside metal portion121does not perform an electrical connecting function since it is not connected to the dummy terminal120to be subsequently formed.

Next, the first insulating layer131is formed on the inside metal portions111and121as illustrated inFIG. 3C, and a second metal layer122ais formed on the first insulating layer131as illustrated inFIG. 3D.

Next, as illustrated inFIG. 3E, a first photoresist layer11is formed on the second metal layer122a.The first photoresist layer11is formed on a portion of the second metal layer122acorresponding to the location where the second metal portion122of the dummy terminal120is to be formed. The first photoresist layer11is patterned by using a second mask (hereinafter referred to as a bump mask). Next, an etching is performed, and at least a portion of second metal layer122ais removed, and the remaining portion of the second metal layer122abecomes second metal portion122of the dummy terminal120is formed, as depicted inFIG. 3F. Following this etching, the first photoresist pattern11is removed as depicted inFIG. 3G.

Subsequently, a second insulating layer132is formed on the second metal portion122of the dummy terminal120and the first insulating layer131as shown inFIG. 3H. Next, as illustrated inFIG. 31, a second photoresist layer12is formed on the second insulating layer132. The second photoresist layer12is patterned to be a third mask (hereinafter referred to as a pad mask) which corresponds to the areas in which the bump portions112and123are to be formed are patterned by using a third mask . The portions in which the bump portions112and123are to be formed are the portions corresponding to and over the inside metal portions111of the connection terminals110and a portion over the second metal portion122of the dummy terminals120.

When an etching is performed in this state, as illustrated inFIG. 3J, the unmasked portions of the second insulation layer132and the first insulation layer12are removed, and the inside metal portions111of the connection terminals110and the inside metal portion122of the dummy terminals120are exposed.

Next, as inFIG. 3K, the bump portions112and123formed of a gold material are attached on the exposed inside metal portions111and second metal portion122.

The second photoresist layer12is then removed, and the driving chip100, and the method is complete, as illustrated inFIG. 3L.

Therefore, the dummy terminals120in driving chip100do not form or provide an electrical connection function are disposed between the connection terminals110. Thus, the dummy terminals120provide support for driving chip100when driving chip100is subjected to mounting forces. The dummy terminals120counter act the external mounting force, a warp transformation is unlikely to occur when pressing the driving chip100to attach it on the pad portion210of the panel200, and a pressure mark due to a warp of the panel200also hardly occurs on the driving chip100.

In addition, since the bump portions112and123formed of a gold material are attached on the inside metal portions111and122formed of an aluminum material, a strong bond between the gold and aluminum metals is obtained, and thus, a stable coupling between the pad portion210and the driving chip100may be secured.

Furthermore, since the driving chip100having the above structure is formed by using only three masks, including the base mask, the bump mask, and the pad mask, there is no burden or increased difficulty due to the increase of the number of mask.

In some embodiments, the dummy terminals120are disposed in a line running in the direction corresponding to the long side of the driving chip100in the central portion thereof is illustrated as an example. However, as illustrated inFIG. 4, a modified driving chip100′ dummy terminals120may be arranged in a plurality of lines.

TAs dummy terminals120is are formed in two or more lines in an empty space between the connection terminals110, the ability of driving chip100′ to resist warp transformations and to hold out against external mounting forces. Additionally, by increasing the number of dummy terminals120, or by forming the dummy terminals120in a plurality of lines, the resistance of the panel20to warp transformations may be increased. In other words, the dummy terminals120may be formed in a plurality of lines within an available space, and a driving chip including the dummy terminals120formed in a plurality of lines may be formed in the same manner through the processes ofFIGS. 3A through 3L.

The driving chip as described herein and the method of manufacturing the driving chip, as described above, may suppress a warp transformation of the driving chip by using a bearing power of the dummy terminals. Furthermore, the phenomenon in which a pressure mark occurs on the driving chip due to a warp of the panel, may be prevented, and thus, the reliability of the driving chip may be improved.

While the inventive concept has been particularly shown and described with reference to exemplary embodiments thereof, they are provided for the purposes of illustration and it will be understood by those of ordinary skill in the art that various modifications and equivalent other embodiments can be made from the inventive concept. Accordingly, the true technical scope of the inventive concept is defined by the technical spirit of the appended claims.