At the same time, the LDD areas 86n of the n-type having a concentration lower than that of the collector area 92c and the emitter area 92e (described later) are formed in the element area 18 of the bi-polar transistor area 80.More specifically, a resist pattern RP5 is formed on the p-type MOS transistor area 30 and the bi-polar transistor area 80 in an area except areas where the collector area 9