A first etching stop layer and an active layer are formed on an inner surface of a first glass substrate, and a second etching stop layer and a cover layer are formed on an inner surface of a second glass substrate. A display media is formed between the first glass substrate and the second glass substrate. A first passivation layer is formed on an outer surface of the second glass substrate. A first etching process is performed to expose the first etching stop layer. A first flexible substrate is formed on the exposed first etching stop layer, and a second passivation layer is formed on the first flexible substrate. The first passivation layer is removed. A second etching process is performed to expose the second etching stop layer. A second flexible substrate is formed on the exposed second etching stop layer, and the second passivation layer is removed.