THE REVERSE ANNEAL OF JUNCTION CHARACTERISTICS IN FORMING SHALLOW P+-N JUNCTION BY BF-2(+) IMPLANTATION INTO THIN CO FILMS ON SI SUBSTRATE

Abstract

Silicided shallow p+-n junctions, formed by BF2+ implantation into thin Co films on Si substrates and subsequently annealed, show a reverse anneal of junction characteristics in the temperature range between 550 and 600-degrees-C. The reverse anneal means a behavior showing the degradation of considered parameters with increasing anneal temperature. A higher implant dosage causes a more distinct reverse anneal. The reverse anneal of electrical characteristics was associated with the reverse anneal of substitutional boron. A shallow p+-n junction with a leakage current density lower than 3 nA/cm2, a forward ideality factor better than 1.01, and a junction depth of about 0.1-mu-m was therefore achieved by just a 550-degrees-C anneal.