Method of manufacturing an organic light emitting display device by patterning and formation of pixel and gate electrodes
A organic light emitting display device includes a thin film transistor (TFT) having a gate electrode, a source electrode and a drain electrode which are insulated from the gate electrode, and a semiconductor layer which is insulated from the gate electrode and which contacts each of the source electrode and the drain electrode; and a pixel electrode electrically connected to one of the source electrode and the drain electrode. The gate electrode is made up of a first conductive layer and a second conductive layer on the first conductive layer, and the pixel electrode is formed of the same material as the first conductive layer of the gate electrode on a same layer as the first conductive layer of the gate electrode.
1. A method of manufacturing an organic light emitting display device, the method comprising:
forming a first conductive layer and a second conductive layer on the first conductive layer, the first conductive layer being formed on a substrate;
forming a patterned photoresist layer on a first area of the second conductive layer corresponding to where a gate electrode is to be formed and on a second area of the second conductive layer corresponding to where a pixel electrode is to be formed, wherein the patterned photoresist layer has a greater thickness at the first area than at the second area;
patterning the first conductive layer and the second conductive layer by removing portions of the first conductive layer and the second conductive layer not covered by the patterned photoresist layer, and removing the patterned photoresist layer on the second area; and
removing the second conductive layer of the second area to form the pixel electrode and removing the patterned photoresist layer remaining on the first area to form the gate electrode,
wherein removing the second conductive layer of the second area to form the pixel electrode and removing the patterned photoresist layer remaining on the first area to form the gate electrode is performed using the same etching process.
2. The method of claim 1 , wherein the first conductive layer is formed of a transparent conductive material.
3. The method of claim 1 , wherein the first conductive layer is formed of a material that is more difficult to etch than a material that forms the second conductive layer.
4. The method of claim 1 , wherein the first conductive layer is formed of indium tin oxide, indium zinc oxide or In 2 O 3 and the second conductive layer is formed of Mo, W, Al, Cu, Ag, or an alloy thereof.
5. The method of claim 1 , wherein the first conductive layer and the second conductive layer are formed sequentially.
6. The method of claim 1 , wherein the first conductive layer and the second conductive layer are formed concurrently.
7. The method of claim 1 , wherein the patterned resist layer on the first area is partially removed in a thickness direction concurrent with the removing of the patterned resist layer on the second area.
8. The method of claim 1 , wherein the forming of the patterned photoresist layer on the first area and the second area is carried out using a halftone mask.
9. The method of claim 1 , further including forming the patterned photoresist layer on a third area of the second conductive layer corresponding to where a wiring electrically connected to the gate electrode is to be formed, concurrently with the forming of the patterned photoresist layer on the first area and the second area, and wherein the thickness of the patterned photoresist layer on the third area is greater than the thickness of the patterned photoresist layer on the second area and further including removing the patterned photoresist layer from the third area concurrently with the removing of the patterned photoresist layer from the first area and the removing of the second conductive layer from the second area.
10. The method of claim 9 , wherein the thickness of the patterned photoresist layer on the third area is equal to the thickness of the patterned photoresist layer on the first area.
11. The method of claim 9 , wherein the forming of the patterned photoresist layer on the first area, the second area and the third area is carried out using a halftone mask.
12. The method of claim 1 , wherein removing the patterned photoresist layer on the second area comprises removing the photoresist layer on the second area and the first layer such that a portion of the patterned photoresist layer remains on the first area.