부산대학교 도서관

Decaborane (B10H14) cluster ions were implanted into n-Si(100) substrates to fabricate shallow p+/n junctions. Implant energies of 2 keV, 5 keV, and 20 keV, equivalent to implant energies of the monomer boron ion of 174 eV, 435 eV, and 1.74 keV, respectively, were used at dosages of 1 1012 /cm2 and 1 1013 /cm2. The implanted samples were then subjected to activation annealing at 800 C, 900 C, and 1000 C for 10 s. By using secondary ion mass spectrometry (SIMS) depth proles, we determined that the depth of the shallow junction (Ds) at a dosage of 1 1013 /cm2 was in the range 12 nm - 45 nm after annealing at 1000 C. Ds and transient enhanced diusion (TED) were greatly reduced at implant energies lower than 5 keV, but thermal diusion (TD) smoothly decreased. In particular, TED was suppressed in the p+/n junction implanted at 2 keV and a dosage of 1 1013 /cm2, and the formation of only a 5.6-nm ultra-shallow junction was identied. This kind of extreme suppression of Ds is thought to result from the formation of well-localized damage with few interstitial defects, which act as a sinks, due to very low-energy cluster ion implantation near the surface region. The p+/n junction exhibited a leakage current density of 1.8 10က12 A/m2 at က2 V.