Patent ID: 11919039
Assignee: BEIJING BOE TECHNOLOGY DEVELOPMENT CO., LTD.
Field: Chemical engineering (Chemistry)
Classification: CPC B | IPC B

Claim 18:
19. The method for manufacturing the acoustic transduction unit according to claim 18, wherein the sacrificial pattern comprises: a first sacrificial sub-pattern and a second sacrificial sub-pattern provided in a stack, wherein the step of forming the sacrificial pattern comprises steps of:
forming a first sacrificial sub-pattern on a side of the first electrode distal to the base substrate;
forming a second sacrificial material film on a side of the first sacrificial sub-pattern distal to the base substrate;
coating a second photoresist film on a side of the second sacrificial material film distal to the first electrode, exposing the second photoresist film by using a gray tone mask, and developing the exposed second photoresist film, so as to obtain a second photoresist pattern, wherein a surface of the second photoresist pattern distal to the base substrate is a slope surface, and a thickness of the second photoresist pattern is gradually reduced in a direction from the center toward the edge of the vibrating cavity;
performing a dry etching process on the second photoresist pattern and the second sacrificial material film to obtain the second sacrificial sub-pattern, wherein a surface of the second sacrificial sub-pattern distal to the first electrode is a slope surface and intersects with a surface of the second sacrificial sub-pattern proximal to the first electrode so as to form the accommodating groove.