| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for manufacturing a superjunction semiconductor device. SOLUTION: Multiple trenches arranged in symmetry and separated from each other intrude as deep as 5-40 microns in an N- silicon epitaxial layer on an N+ body. These wells comprise a circular cross-section plane, with its diameter being about 9 microns. Boron ions are implanted into a trench wall by an ion implantation beam tilted slightly with respect to the trench axis. A wafer is intermittently or continuously rotated with an axis which is not 90 deg. with respect to its surface, as the center. Thus, the implantation beam becomes oblique, and makes the boron ion distribution at the inside surface of the trench more uniform.
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