公开(公告)号：US3802968A

公开(公告)日：1974-04-09

申请号：US87501169

申请日：1969-11-10

Applicant: IBM

Inventor： GHOSH H ,  WAJDA E

IPC: H01L21/00 ,  H01L21/74 ,  H01L27/00 ,  H01L29/08 ,  H01L7/00 ,  H01L19/00

CPC classification number: H01L29/0826 ,  H01L21/00 ,  H01L21/74 ,  H01L27/00 ,  Y10S148/037 ,  Y10S148/049 ,  Y10S148/085 ,  Y10S148/098 ,  Y10S148/145 ,  Y10S148/151 ,  Y10S257/919

Abstract: A process for forming a self-isolated monolithic device by providing a substrate of a first conductivity type and forming an epitaxial layer of same conductivity type over the substrate. The epitaxial layer and the substrate are subjected to treatment so as to outdiffuse an impurity of opposite conductivity from the substrate and into the epitaxial layer so as to form a region which constitutes an element of the integrated circuit device and also defines an isolation PN junction with the epitaxial layer. Further, a pedestal transistor process forms a pedestal transistor for monolithic circuits by outdiffusing an impurity to form a subcollector region and outdiffusing another impurity having a higher diffusion rate to form the pedestal region. An extrinsic collector region defines an extrinsic junction with a lighter doped extrinsic base region so as to reduce overall base to collector capacitance.

公开(公告)号：US3730786A

公开(公告)日：1973-05-01

申请号：US3730786D

申请日：1970-09-03

Applicant: IBM

Inventor： GHOSH H

IPC: H01L21/00 ,  H01L21/8228 ,  H01L27/082 ,  H01L7/36 ,  H01L11/00 ,  H01L19/00

CPC classification number: H01L27/0826 ,  H01L21/00 ,  H01L21/82285 ,  Y10S148/037 ,  Y10S148/043 ,  Y10S148/085 ,  Y10S148/151 ,  Y10S148/157

Abstract: A METHOD FOR FABRICATING A COMPLEMENTARY PAIR OF TRANSISTORS HAVING CLOSELY MATCHED CHARACTERISTICS. A HIGH PERFORMANCE NPN TRANSISTOR IS MATCHED TO A PNP TRANSISTOR WHOSE PERFORMANCE IS UPGRADED THROUGH THE USE OF A DOPED OXIDE FOR SIMULTANEOUSLY DIFFUSING THE BASE OF THE PNP TRANSISTOR AND THE EMITTER OF THE NPN TRANSISTOR. AFTER THE BASE DIFFUSION IS COMPLETED, THE DOPED OXIDE IS ETCHED AWAY ONLY FROM THE BASE REGION OF THE PNP TRANSISTOR AND DIFFUSION CONDITIONS ARE REESTABLISHED. THE BASE DOPING OF THE PNP TRANSISTOR THEN REDISTRIBUTES TO PRODUCE A LOWER SURFACE CONCENTRATION AND A SHARPER GRADIENT AT THE COLLECTOR BASE JUNCTION WHILE THE DOPED OXIDE REMAINING OVER THE NPN EMITTER ACTS AS A CONTINUING SOURCE OF EMITTER IMPURITY FOR ENHANCED EMITTER EFFICIENCY.