A complementary transistor is constituted of a first transistor TR1 and a second transistor TR2, active regions 32, 42 of the respective transistors are formed by layering first A layers 33, 43 and the first B layers 35, 45 respectively, surface regions 201, 202 provided in a base correspond to first A layers 33, 43 respectively, first B layers 35, 45 each have a conductivity type different from that of the first A layers 33, 43, and extension layers 36, 46 of the first B layer are provided on insulation regions 211,212 respectively.