Japan Display Inc.

Panasonic Liquid Crystal Display Co., Ltd.

Hitachi Displays, Ltd.

Makoto Kurita

Jun Gotoh

Hiroaki Asuma

Eiji Oue

Katsumi Nakayashiki

Taro Asai

An organic EL display device includes scanning lines, video signal lines, and pixels, each including a TFT having a semiconductor layer and an organic EL layer located between a lower electrode and an upper electrode. A source electrode connecting the semiconductor layer and the lower electrode is formed of three layers including a barrier metal, an Al-containing metal, and a cap metal. The barrier metal is formed of a first layer in contact with the semiconductor layer and a second layer in contact with the Al-containing metal. Each of the first layer, the second layer, and the cap metal is formed of a metal comprising a high melting point metal, and an amount of oxygen in the first layer is larger than an amount of oxygen in the second layer.

Display device comprising a TFT with a barrier metal formed of a first layer and a second layer wherein an amount of oxygen in the first layer is larger than in the second layer

A contact resistance in a through-hole with a source or a drain electrode connected to a TFT is decreased, thereby improving the operation efficiency of a display device. In the through-hole, a source portion of the TFT is connected to a source electrode. The source electrodeis formed of three layers comprising a barrier metal, an Al alloy, and a cap metal. The barrier metal is divided into a lower layerin contact with the semiconductor layer and an upper layerin contact with the Al alloy. The lower layerof the barrier metal is formed by sputtering, the lower layeris heat-treated and, subsequently, an upper layerof the base metal, the Al alloy, and the cap metalare formed continuously by sputtering. Since the upper layerof the barrier metal in contact with the Al alloyis not oxidized, increase in the contact resistance in the through-hole can be prevented.

Liquid crystal display device comprising a TFT with a barrier metal formed of a first layer and a second layer wherein the first layer is denser than the second layer

A break on a video signal line is prevented during patterning on the video signal line. A video signal line, a drain electrode, and a source electrode are simultaneously formed in the same layer. The video signal line includes three layers: a base layer, an AlSi layer, and a cap layer. Conventionally, an alloy having a high etching rate is formed at the boundary between the AlSi layer and the cap layer, causing breakage during patterning on the video signal line. According to the present invention, in the formation of the video signal line, the AlSi layer is formed by sputtering, a TFT is exposed to the atmosphere to form an Al oxide layer on the surface of the AlSi layer, and then the cap layer is formed by sputtering. Thus, the formation of an alloy having a high etching rate on a part of the AlSi layer is prevented, precluding the occurrence of a break on the video signal line.

Liquid crystal display device and manufacturing method thereof

The present invention provides a display device which can prevent the deterioration of a transparent conductive film attributed to a cell reaction without pushing up a cost of a film forming device. The display device includes a first conductive layer which is formed of a transparent conductive film containing indium oxide as a main component, a conductive background layer which is formed on the first conductive layer, a second conductive layer which is formed of a film containing Al as a main component on the background layer, and a third conductive layer which is formed of the same material as the second conductive layer on the second conductive layer. On an interface between the second conductive layer and the third conductive layer, positions of grain boundaries are arranged discontinuously. Further, the background layer is a film which contains any one of Mo, Ti and Ta as a main component. Still further, the third conductive layer is used as a reflective electrode.

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Mobara, Japan

Makoto Kurita