| 摘要 |
An object of the present invention is to provide an IBGT which satisfied with a reliable high breakdown-voltage proof characteristic and occupies smaller device formation region with lower power consumption. An n-- type semiconductor layer 38 is formed on a part where has tendency to cause break down, and an n - type semiconductor substrate 36 is formed underneath the n-- type semiconductor layer 38. As a result, the value of theoretical breakdown-voltage of the n-- type semiconductor layer 38 become greater than that of the n - type semiconductor substrate 36. Also, the n - type semiconductor substrate 36 having lower electric resistance is located underneath the n-- type semiconductor layer 38. Therefore, lower power consumption is expected because electric resistance of the part where determines a power consumption of the IGBT is decreased. <IMAGE> |
