HIGH-RESOLUTION DAMAGE DEPTH PROFILES OF UNANNEALED SUB-100 NM B+ IMPLANTS IN (100) SILICON

Si (100) wafers were boron implanted using an xRLEAP ion implanter at energies of 0.2, 1.0, and 3.0 keV all at a dose of 1 x 10(14) cm(-2). Advanced spreading resistance (SR) measurements were performed on the as-implanted samples to obtain high-resolution profiles of the damaged layer produced during implantation. The measured spreading resistance was highest at, or near, the surface on all samples. The 1.0 and 3.0 keV implants also showed minima in the SR near the substrate. The as-i mplanted samples were examined with secondary ion mass spectrometry to determine the dopant profile. Forward and reverse Schottky I-V measur ements were also done on the same as-implanted samples with a mercury probe. The forward Schottky I-V curves for the 0.2 and 1.0 keV samples showed nonideal Schottky diode behavior. The 3.0 keV sample was simil ar to that of a good quality Schottky diode and had an ideality factor of 1.28. The reverse Schottky I-V data were processed to obtain the e ffective dielectric constants for each sample; a neutron transmutation -doped (NTD) wafer was used as a reference. The dielectric constants w ere 0.77, 1.467, 2.797, and 10.26 for the 0.2, 1.0, and 3.0 keV and NT D samples, respectively. (C) 1998 American Vacuum Society.