| 摘要 |
PURPOSE:To obtain electrodes having a field plate structure, which does not require step parts in a field insulating film, by forming a reverse conducting type second impurity region, whose impurity concentration is larger than that of the surface of a substrate and lower than that of the surface of a first impurity region, on the surface of the substrate under the outer periphery of a conductor layer. CONSTITUTION:In the specified region of a silicon layer 6 having the n type impurity concentration of about 2X10<14>cm<-3>, n type impurity ions are implanted. Then annealing is performed, and a high impurity concentration region 7 of about 6-10X10<14>cm<-3> is formed. Thereafter, a p type base region 10 is formed. Then, by using a photolithography method, a silicon dioxide film 9 is removed from an emitter region. An emitter 12 having the impurity concentration of about 1X10<21>cm<-3> is formed by diffusing n type impurities. An opening is formed in each electrode forming region by using the photolithography method. A high concentration region of impurities is formed in the contact region of each electrode. Then, an aluminum film is formed, and the film is patterned. Thus a collector electrode 14, a base electrode 15 and an emitter electrode 16 are formed. |
