Flexible display device with hardened layer, display apparatus, and method for manufacturing the flexible display device

A method for manufacturing an organic light emitting diode (OLED) flexible display device, comprising:

• providing a flexible display panel, a front surface of the flexible display panel provided with a circuit bonding region, the flexible display panel comprising a first flexible substrate, the circuit bonding region being above the first flexible substrate, a hardened layer being formed on the first flexible substrate, wherein the hardened layer is at a position corresponding to the circuit bonding region, the hardened layer is in a non-display region of the flexible display panel, a thickness of the hardened layer ranges from 5 micrometers to 50 micrometers, an area of the hardened layer is greater than or equal to an area of the circuit bonding region, and the flexible display panel further comprises:
• a second flexible substrate, wherein the hardened layer is formed between the first flexible substrate and the second flexible substrate, and an insulating layer between the first flexible substrate and the second flexible substrate, wherein the insulating layer covers the hardened layer, the hardened layer is between the insulating layer and the second flexible substrate, the first flexible substrate is above the insulating layer, and the second flexible substrate is below the insulating layer, and the providing of the flexible display panel comprises:
• forming a barrier layer on the first flexible substrate, forming TFT array elements on the barrier layer, the first flexible substrate being between the hardened layer and the TFT array elements, forming a light emitting layer on the TFT array elements, and forming a thin film encapsulation on the light emitting layer, wherein the barrier layer, the TFT array elements, the light emitting layer, and the thin film encapsulation are in a display region of the flexible display panel;
• and
• bonding bumps of an integrated circuit layer to the circuit bonding region to bond the integrated circuit layer to the flexible display panel.