Patent ID: 9035316
Filing Date: 2015-05-19
Classification: G02F,H01L

Abstract:
1. A device comprising: a substrate; a p-channel transistor over the substrate; a current supply line electrically connected with a source of the p-channel transistor; an anode of an EL element electrically connected with a drain of the p-channel transistor; a light-emitting layer over the anode; and a cathode over the light-emitting layer, wherein a semiconductor layer of the p-channel transistor comprises a channel forming region, a first impurity region of one conductivity type, and a second impurity region of said one conductivity type between said channel forming region and said first impurity region, wherein a gate electrode of the p-channel transistor comprises a first conductive layer, a second conductive layer, and a third conductive layer, wherein the first conductive layer extends beyond edges of the second conductive layer, wherein the second conductive layer is provided directly on a first upper surface of the first conductive layer, wherein the third conductive layer is provided over a second upper surface of the first conductive layer and the second conductive layer, wherein the third conductive layer is directly in contact with the second upper surface of the first conductive layer and directly in contact with upper and side surfaces of the second conductive layer, wherein the third conductive layer extends on the second upper surface of the first conductive layer from the side surface of the second conductive layer to a side surface of the first conductive layer, wherein the first conductive layer and the third conductive layer comprise a material selected from the group consisting of silicon, titanium, tantalum, tungsten and molybdenum, wherein the entire first conductive layer and the entire third conductive layer comprise different materials, wherein the first conductive layer and the second conductive layer comprise different materials, and wherein the second conductive layer and the third conductive layer comprise different materials.