22nm node p+ junction scaling using B36H44 and laser annealing with or W/O PAI

B
36
H
44
molecular dopants were implanted at 100eV and 1E15/cm
²
B equivalent energy and dose to achieve Xj<7nm and selected wafers also had various PAI (pre-amorphizing implantation) using Ge 10keV, Xe 14keV and In 14keV to create an amorphous layer 16–17nm deep. All the wafers were MSA (msec annealed) by DSA laser at 1175°C, 1225°C, 1275°C and 1325°C and the results show that the Rs and Bss values for B
36
H
44
without PAI was always better than those reported using monomer B and BF
2
with MSA even though the retained dose was only 67% compared to 100% for monomer B and 55% for BF
2
and we noted that the surface oxide directly affects the retained dose. Adding Ge or In PAI had no effect on dopant activation due to the self-amorphization effects of B
36
H
44
however, Xe-PAI improved activation by 20% but degraded junction leakage. In-PAI also had the highest lifetime. However, we noted that Xe-PAI behaves differently compared to Ge-PAI and In-PAI, TW values were always much higher and independent of the anneal technique (MSA, spike/RTA or furnace anneal) even though no defects could be detected by X-TEM suggesting uniform distribution of vacancy cluster defects throughout the amorphous region.