Atoms of B were incorporated into (100) wafers by heating the substrates (800C, 0.5h) in a B2H6/H2 atmosphere and by subsequent rapid thermal annealing at temperatures above 900C. The atomic and carrier concentration profiles of B-doped layers were examined by means of secondary ion mass spectrometry and differential Hall measurements, respectively. The results clearly showed that ultra-shallow p+ layers, 30nm-thick and with a surface carrier concentration of 7.26 x 1019/cm3, could be formed by B diffusion at 800C and by subsequent rapid thermal annealing at 100C.

T.Inada, A.Kuranouchi, H.Hirano, T.Nakamura, Y.Kiyota, T.Onai: Applied Physics Letters, 1991, 58[16], 1748-50