Formation method of contact structure, contact structure and semiconductor device

• Main Authors: HUANG XIN, WANG SHIXIN
• Format: Patent
• Language: Chinese; English
• Published: 07.02.2023
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; SEMICONDUCTOR DEVICES

The invention discloses a contact structure forming method, a contact structure and a semiconductor device, and the method comprises the steps: providing a substrate which is internally provided with a plurality of isolation regions, and enabling the isolation regions to isolate a plurality of active regions on the substrate; etching the active region and the isolation region for the first time at the same time to form a first contact through hole, and forming a convex active region at the position of the active region at the bottom of the first contact through hole; depositing a first dielectric layer to cover the side wall and the bottom of the first contact through hole; and etching the bottom of the first contact through hole for the second time to form a contact structure with the target depth. By backfilling the bottom of the first contact through hole with the first dielectric layer and etching again to reach the target depth, the height difference of the bottom of the first contact through hole on dif