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Pre-amorphization scheme has been widely used to form shallow source/drain extension for deep sub-micron CMOS technology. In this paper, different Sb and In implantation conditions (various implant energies and doses) were used before BF2 and As HDD implant to study their effects on pMOS and nMOS characteristics, respectively, such as Lgmin (the gate length at Ioff equals InA/micrometers at Vg EQ 0, Vd equals 1.5 V), Idrive (drive current when Vg equals Vd equals 1.5 V), and diode leakage. These characteristics will also be compared with those obtained from devices without the pre-amorphization. TEOS 1st spacer in different thickness and various final RTA temperatures were also used to study their effect on the drive current. The key results are as follows: (1) A 4% improvement in Idrive(strong) (from 185 (mu) A/micrometers to 193 (mu) A/micrometers ; the drive current at Ioff equals InA/micrometers at supplying voltage of 1.5 V and tox approximately equals 39 angstroms) and approximately 0.02 micrometers reduction in Lgmin (from approximately 0.16 micrometers to approximately 0.14 micrometers ) were observed for the pMOS devices with Sb pre-amorphization when the same thickness of the 1st spacer was used. These improvements are due to the formation of a more shallow and abrupt HDD when pre-amorphization is used. (2) With the requirements of Lgmin equals approximately 0.16 micrometers , a p-channel Idrive(strong) equals 211 (mu) A/micrometers at Lgmin equals approximately 0.16 micrometers were obtained with a thin 1st spacer and with Sb pre-amorphization in this study. For the same Lgmin requirement, a thick 1st spacer (150 angstroms thicker than the thin one) had to be used for a device without the pre-amorphization, which resulted in a higher Rsd and thus degraded the drive current to Idrive(strong) equals 185 (mu) A/micrometers . (3) The Sb implant conditions do not form an effective pocket implant doping for either case studied. A similar improvement in Lgmin is observed for different annealing temperatures studied. (4) In contrast to the Lgmin of a pMOS, the junction diode leakage is sensitive to the Sb implant condition. The diode leakage increases with Sb implant energy and dose. (5) Contrary to the Sb pre- amorphization cases, no significant improvement in either Idrive and Lgmin is observed in the nMOS devices with In pre-amorphization.
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