Forming doped regions in semiconductor strips

• Main Authors: Tsai, Shin-Yeu, Huang, Shih-Wen, Cheng, Kai Hung, Lin, Chia-Hui
• Format: Patent
• Language: English
• Published: 23.04.2019
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; SEMICONDUCTOR DEVICES

A method includes etching a semiconductor substrate to form trenches, with a portion of the semiconductor substrate between the trenches being a semiconductor strip, and depositing a dielectric dose film on sidewalls of the semiconductor strip. The dielectric dose film is doped with a dopant of n-type or p-type. The remaining portions of the trenches are filled with a dielectric material. A planarization is performed on the dielectric material. Remaining portions of the dielectric dose film and the dielectric material form Shallow Trench Isolation (STI) regions. A thermal treatment is performed to diffuse the dopant in the dielectric dose film into the semiconductor strip.