MANUFACTURE OF BIMOS SEMICONDUCTOR DEVICE

摘要

PURPOSE:To enhance a characteristic of a horizontal-type transistor without increasing the number of production processes by a method wherein a doping operation of the same concentration as that of a well for a MOS transistor is executed to a base region of the horizontal-type transistor. CONSTITUTION:Because an n-type epitaxial layer becomes a base region 3 for a pnp transistor as a horizontal-type transistor, an additional doping operation to the region is executed simultaneously with an n-type doping operation to a well for a p-channel MOS transistor. The doping operation to the well region 12 for the p-channel MOS transistor is executed at a doping concentration of about 10<16> atoms/cm<2> and with a thickness of 2 mum. The doping operation at the same concentration and with the same depth is executed to the base region 3 for the pnp transistor. The horizontal-type transistor 51 where an emitter layer 5, a collector layer 6 and a base layer 6 are formed inside an additionally doped base layer 13 is constituted in this manner.