公开(公告)号：US3681147A

公开(公告)日：1972-08-01

申请号：US3681147D

申请日：1970-01-22

Applicant: IBM

Inventor： DHAKA VIR A ,  KOZIK ANDREW F

IPC: H01L29/73 ,  H01L21/00 ,  H01L21/265 ,  H01L21/283 ,  H01L21/316 ,  H01L21/329 ,  H01L21/331 ,  H01L21/768 ,  H01L23/485 ,  H01L23/522 ,  H01L7/54

CPC classification number: H01L23/485 ,  H01L21/00 ,  H01L21/31687 ,  H01L21/76888 ,  H01L23/522 ,  H01L2924/0002 ,  H01L2924/00

Abstract: SEMICONDUCTORS HAVING VERY NARROW BASE WIDTHS CAN BE FABRICATED BY USING ION IMPLANTATION THROUGHTHE CONTACT METALLIZATION AS A MASK, THEN EXPANDING AND PASSIVATING THE METALLIZATION BY ANODIZATION SO AS TO PROTECT THE SEMICONDUCTOR JUNCTION. ALUMINUM METALLIZATION HAS PREDICTABLE EXPANSION CHARACTERISTICS AS IT OXIDISES OR IS ANODIZED, AND THE OXIDE HAS INSULATING PROPERTIES. THIS PREDICTABLE EXPANSION OF ALUMINUM OXIDE PERMITS A DYNAMIC CONTROL OF THE SIZE AND SHAPE RELATIONSHIP BETWEEN ADJACENT SEMICONDUCTIVE REGIONS SUCH AS EMITTER AND BASE OR BASE-COLLECTOR. THE EXPANSION OF THE CONTACT METALLIZATION PROVIDES A MASK OPENING WITH CLOSELY CORRESPONDING DIMENSIONS AND PERMITS VERY CLOSE CONTROL OF NARROW SEMICONDUCTOR REGIONS.