| 摘要 |
PURPOSE:To reduce the expansion of a base and improve a characteristic of noise by a method wherein a base layer deeper than an emitter and high concentration diffusion having the same polarity are formed to the base. CONSTITUTION:The deep n<+> high concentration diffusion layer 13 having polarity the same as the base 4 is made up. A characteristic of noise can be improved because a resistance value of a resistor 12 among resistance values forming base expansion resistors r can be reduced by making up the n<+> high concentration diffusion layer 13. Preferably, the n<+> high concentration diffusion layer 13 is ideally built up in a shape that is deep up to depth connected to a n<+> buried region 2. |
