Flexible display and manufacturing method thereof

1. A method of manufacturing a flexible display, comprising:

forming a first barrier layer on a flexible substrate;

forming a second barrier layer comprising silicon nitride on the first barrier layer;

exposing the second barrier layer to the air in order to release stress of the second barrier layer and form an oxide film on the second barrier layer;

forming a first buffer layer comprising silicon nitride having the same film quality as the second barrier layer on the second barrier layer;

forming a second buffer layer on the first buffer layer; and

forming a thin film transistor on the second buffer layer.

2. The method of claim 1 , wherein

the flexible substrate comprises at least one polymer material layer comprising polyimide.

3. The method of claim 2 , wherein the flexible substrate includes:

a first flexible substrate;

an intermediate barrier layer formed on the first flexible substrate; and

a second flexible substrate formed on the intermediate barrier layer,

wherein the intermediate barrier layer comprises a same material as the first barrier layer.

4. The method of claim 3 , further comprising:

forming an adhesive layer between the first flexible substrate and the second flexible substrate,

wherein the adhesive layer comprises at least one of amorphous silicon on which a P-type or N-type conductive impurity is doped, or hydrogenated amorphous silicon.

5. The method of claim 3 , wherein

the intermediate barrier layer is formed to have a thickness of about 1000 Å to about 6000 Å.

6. The method of claim 3 , wherein

the first flexible substrate and the second flexible substrate comprise polyimide.

7. The method of claim 3 , wherein

each of the first flexible substrate and the second flexible substrate is formed to have a thickness of about 8 μm to about 12 μm.