Display module, manufacturing method, and display device

A method for manufacturing a display module, the method comprising:

• providing a display screen, the display screen comprising a test area and a non-test area, wherein the non-test area is near an end at which a first binding area of the display screen is located;
• providing an auxiliary functional layer on the back side of the display screen, wherein an extended bonding surface is formed on a side of the auxiliary functional layer facing away from the display screen, or is formed by a part of the back side of the display screen which is not covered by the auxiliary functional layer, wherein the extended bonding surface is at least partially located in the non-test area and near the end at which the first binding area is located;
• cutting away the display screen in the test area, or cutting away the display screen in the test area and the auxiliary functional layer, the first binding area and the extended bonding surface being adjacent to a first end of the display screen in the non-test area;
• binding the first binding area of the display screen in the non-test area to a second binding area of an external circuit assembly, a part of the external circuit assembly that extends beyond the first end of the display screen forming a first step surface;
• and
• manufacturing a sealant, wherein the sealant covers at least a part of the first step surface, and integrally covers and is bonded to at least a part of the first end and the extended bonding surface.