Title :
Epi avoidance for CMOS logic devices using MeV implantation
Author :
Borland, John O. ; Wristers, Derick ; Walker, Julian
Author_Institution :
Ion Technol. Div., Genus Inc., Newburyport, MA
Abstract :
Using MeV ion implantation and Cz bulk wafer denuding/gettering techniques, we have successfully demonstrated in bulk (non-epi) wafers superior latch-up performance and equivalent surface silicon quality (gate oxide integrity and junction leakage current) to that of p/p+ epi wafers resulting in direct retrofit replacement of epi wafers in manufacturing. Latch-up device characteristics will be presented comparing epi, retrograde wells, buried layers and BILLI (Buried Implanted Layer for Lateral Isolation) structures, Up to a 30× reduction in lateral current gain (B1) was measured resulting in a 5× increase in n+ trigger current at <2.0 um n+ to p+ spacing. Also, optimizing various pre-process and/or process induced denuding and gettering have resulted in epi quality bulk Cz wafer surfaces. For a CMOS Logic manufacturing point of view, up to 16% reduction in total process cycle time/complexity can be realized equating to a cost savings of >$229 per 200 mm wafer. This paper summarizes the various MeV epi replacement alternatives describing the advantages and limitations of each from a production implementation point of view
Keywords :
CMOS logic circuits; buried layers; getters; ion implantation; isolation technology; BILLI; Buried Implanted Layer for Lateral Isolation; CMOS logic device manufacturing; Cz bulk wafer; MeV ion implantation; Si; buried layer; denuding; gate oxide integrity; gettering; junction leakage current; latch-up; lateral current gain; retrofit epi replacement; retrograde well; surface silicon quality; trigger current; CMOS logic circuits; CMOS process; Current measurement; Gain measurement; Gettering; Ion implantation; Leakage current; Logic devices; Manufacturing; Silicon;
Conference_Titel :
Ion Implantation Technology. Proceedings of the 11th International Conference on
Conference_Location :
Austin, TX
Print_ISBN :
0-7803-3289-X
DOI :
10.1109/IIT.1996.586102