| 摘要 |
PROBLEM TO BE SOLVED: To provide a recrystallization and activation heat treatment technique which changes an ion implanted region into a single crystal type and to enhance the breakdown strength of a silicon carbide semiconductor device. SOLUTION: P-type impurities are implanted at an acceleration energy of 1 MeV or higher. After that, a heat treatment is executed by a laser. Thereby, the implanted impurities are activated, and p- type base regions 3a, 3b are recrystallized. For example, by an excimer laser, the laser is irradiated sequentially toward upper-side ends from lower-side ends of the p- type base regions 3a, 3b. Thereby, the crystal type of an n+ type epitaxial layer 2 which is situated under the p- type base regions 3a, 3b is made to succeed, and the p- type base regions 3a, 3b are formed to be of the same crystal type. Consequently, the breakdown strength of the silicon carbide semiconductor device is enhanced more than in a case in which the central part of the p- type base regions 3a, 3b is formed of 3C-SiC.
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