US 12,294,043 B2
Drive backplane and preparation method thereof, display panel, and display device
Wei Yang, Beijing (CN); Ke Wang, Beijing (CN); and Muxin Di, Beijing (CN)
Assigned to BOE Technology Group Co., Ltd., Beijing (CN)
Appl. No. 17/280,387
Filed by BOE Technology Group Co., Ltd., Beijing (CN)
PCT Filed Jan. 22, 2020, PCT No. PCT/CN2020/073910
§ 371(c)(1), (2) Date Mar. 26, 2021,
PCT Pub. No. WO2021/147039, PCT Pub. Date Jul. 29, 2021.
Prior Publication US 2022/0115572 A1, Apr. 14, 2022
Int. Cl. H01L 33/62 (2010.01); H01L 33/00 (2010.01)
CPC H01L 33/62 (2013.01) [H01L 33/005 (2013.01); H01L 2933/0066 (2013.01)] 16 Claims
OG exemplary drawing
 
1. A drive backplane, comprising:
a flexible substrate on which a first via hole is provided;
a first passivation layer located on one side of the flexible substrate, wherein the first passivation layer is provided with a second via hole, and an orthographic projection, on the flexible substrate, of the second via hole is at least partially overlapped with an orthographic projection, on the flexible substrate, of the first via hole;
a thin film transistor located on a side, facing away from the first passivation layer, of the flexible substrate; and
an electrical connecting structure, comprising a signal trace and a connecting terminal; wherein the connecting terminal is located on a side, close to the first passivation layer, of the flexible substrate and comprises a first portion located between the flexible substrate and the first passivation layer and a second portion located within the second via hole, and the orthographic projection, on the flexible substrate, of the second via hole is located within an orthographic projection, on the flexible substrate, of the connecting terminal; and the signal trace is located on the side, facing away from the first passivation layer, of the flexible substrate, is electrically connected to the thin film transistor and electrically connected to the connecting terminal through the first via hole;
wherein the drive backplane further comprises:
a second passivation layer located between the flexible substrate and the connecting terminal,
wherein the second passivation layer is provided with a third via hole, the third via hole and the first via hole penetrate through each other along a thickness direction of the second passivation layer, and the signal trace is electrically connected to the connecting terminal through the first via hole and the third via hole;
a size of an opening on a side, facing the connecting terminal, of the third via hole is smaller than a size of a surface of a side, facing the third via hole, of the connecting terminal; and
a side face of the connecting terminal and an edge area of the surface of the side, facing the third via hole, of the connecting terminal are coated by the second passivation layer, so that the second passivation layer coats the side face and a surface edge of the second portion of the connecting terminal.