公开(公告)号：US3826698A

公开(公告)日：1974-07-30

申请号：US28438172

申请日：1972-08-28

Applicant: IBM

Inventor： ANTIPOV I ,  MELZER P

IPC: H01L21/8222 ,  H01L27/00 ,  H01L27/06 ,  H01L27/082 ,  H01L7/44

CPC classification number: H01L27/0826 ,  H01L21/8222 ,  H01L27/00 ,  H01L27/0658 ,  Y10S148/03 ,  Y10S148/037 ,  Y10S148/085 ,  Y10S148/151

Abstract: A PROCESS FOR FORMING A PEDESTAL BASE TRANSISTOR IN WHICH A BURIED LAYER OF A FIRST CONDUCTIVITY TYPE IS DIFFUSED INTO A SUBSTRATE OF A SECOND CONDUCTIVITY TYPE. IMPURITIES OF THE SECOND CONDUCTIVITY TYPE, WHICH HAVE A HIGHER DIFFUSION RATE THAN THE DOPANT WHICH FORMS THE BURIED LAYER, ARE DIFFUSED INTO A LIMITED AREA OF THE BURIED LAYER. AN EPITAXIAL LAYER IS FORMED ON THE SURFACE OF THE SEMICONDUCTOR. DURING THE GROWTH OF THE EPITAXIAL LAYER, THE PREVIOUSLY DIFFUSED REGIONS OUTDIFFUSE INTO THE EPITAXIAL REGION. THE OUTDIFFUSION OF THE SECOND CONDUCTIVITY TYPE, DUE TO ITS FASTER DIFFUSING CHARACTERISTICS, APPROACHES THE SURFACE OF THEEPITAXIAL LAYER MORE CLOSELY THAN DOES THE BURIED LAYRE, THEREBY FORMING A PEDESTAL REGION. A SECOND DIFFUSION OF THE FAST DIFFUSING MATERIAL IS MADE THROUGH THE SURFACE OF THE EPITAXIAL LAYER AND CONTACTS THE PEDESTAL, THEREBY RESULLTING IN A HIGHLY DOPED PEDESR TAL TAL BASE REGION. DIFFUSED ISOLATION REGIONS AND AN EMITTER REGION ARE FORMED TO COMPLETE THE DIVICE IN MONOLITHIC FORM A METHOD FOR SIMULTANEOUSLY FORMING A SECOND TRANSISTOR OF THE COMPLEMENTARY TYPE TO THE FIRST TRANSISTOR USING THE SAME PROCESS STEPS IS ALSO DESCRIBED.

公开(公告)号：US3752715A

公开(公告)日：1973-08-14

申请号：US3752715D

申请日：1971-11-15

Applicant: IBM

Inventor： ANTIPOV I ,  OBERAI A

IPC: H01L21/331 ,  H01L21/8228 ,  H01L27/082 ,  H01L29/417 ,  H01L29/73 ,  H01L7/44 ,  H01L7/64

CPC classification number: H01L21/82285 ,  H01L27/0826 ,  Y10S148/037 ,  Y10S148/053 ,  Y10S148/085 ,  Y10S148/151

Abstract: COMPLEMENTARY NPN AND PNP TRANSISTORS ARE PREPARED SIMULTANEOUSLY WHICH HAVE PROPERTIES OF A HIGH FREQUENCY RESPONSE. SELECTED IMPURITY CONCENTRATIONS ARE EMPLOYED WHEREBY THE SECOND EMITTER DIFFUSION IS PERFORMED WITH THE FIRST EMITTER AREA UNMASKET. THIS ELIMINATES AND EMITTER CONTACT OPENING STEP SUCH THAT EACH CONTACT AREA AND EMITTER ARE CO-EXTENSIVE. OTHER CIRCUIT COMPONENTS SUCH AS RESISTORS AND DIODES ARE ALSO FORMED DURING THE FORMATION OF THE NPN AND PNP TRANSISTORS.