| 摘要 |
PROBLEM TO BE SOLVED: To form insulation-separated planar type photoelectricity generating cells in a single wafer by forming the cells by etching an intersecting trench array surrounding a diffusion area and filling up the trenches of the array with an insulating material and polysilicon. SOLUTION: Shallow N<+> -type diffusion layers 20, 21, and 22 are formed in the surface area of a silicon wafer substrate 10 by injecting an N-type dopant into the substrate 10. Successively, P<-> -type contact rings 25, 26, and 27 are formed by injecting boron and trenches are formed in a grid. The trenches form insulation-separated tabs or cells in the substrate 10. After oxide layers 50 and 51 are formed on the internal surfaces of the trenches, the trenches are filled up with polysilicon 52. Then upper-layer oxide layers 60 are deposited and contact strips 70 and 71 are formed. Therefore, planar type photoelectricity generating cells can be formed in a single wafer and, at the same time, the cells can be integrated with a power device in the wafer. |
