Japan Display Inc.

Panasonic Liquid Crystal Display Co., Ltd.

Taro Asai

Hiroaki Asuma

Jun Gotoh

Eiji Oue

Makoto Kurita

Katsumi Nakayashiki

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

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Chiba, Japan

Taro Asai