Flexible display substrate module and method of manufacturing flexible display device

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

providing a base substrate;

adhering an adhesive part including a release paper to the base substrate, wherein the release paper is formed on an upper surface of the adhesive part;

pressing an upper surface of the release paper with a roller after adhering the adhesive part to the base substrate, wherein the adhesive part is formed to be thin and uniformly spread on the base substrate;

detaching the release paper from the adhesive part;

adhering a flexible substrate to the adhesive part;

forming a protective layer covering side surfaces of the flexible substrate and of the adhesive part to form a flexible display substrate;

forming display elements on the flexible display substrate, and

separating the flexible substrate from the adhesive part using a separating solution, wherein the separating solution is applied on an interfacial surface between the flexible substrate and the adhesive part and an interfacial surface between the base substrate and the adhesive part,

wherein the surface of the protective layer has the same plane in the region of the flexible substrate and in the region of a exposed base substrate,

wherein a first portion of the protective layer facing an upper surface of the base substrate is thicker than a second portion of the protective layer facing an upper surface of the flexible substrate,

wherein the first portion of the protective layer is disposed on a total region of a peripheral area of the base substrate and a height of the surface of the first portion in the total region of the peripheral area of the base substrate is higher than a height of the surface of the flexible substrate,

wherein the adhesive part includes a first adhesive material and a second adhesive material,

wherein the first adhesive material has a first adhesive force with respect to the base substrate, and the second adhesive material has a second adhesive force with respect to the flexible substrate,

wherein the first adhesive force is substantially different from the second adhesive force,

wherein the second adhesive force is smaller than the first adhesive force easily to separate the flexible substrate,

wherein the forming of the protective layer includes,

forming a preliminary protective layer by covering the base substrate with an organic material; and curing the preliminary protective layer.

2. The method according to claim 1 , wherein curing the preliminary protective layer includes one of heating or lighting the preliminary protective layer.

3. The method according to claim 1 , wherein the protective layer covers an exposed upper surface of the base substrate.

4. The method according to claim 1 , wherein the protective layer covers an upper surface of the flexible substrate.

5. The method according to claim 1 , wherein the protective layer is formed by a spin coating process.

6. The method according to claim 1 , further comprising pressing an upper surface of the flexible substrate with a roller after adhering the adhesive part to the flexible substrate.

7. The method according to claim 1 , wherein a height of the first portion of the protective layer is identical to a height of the second portion of the protective layer.