Device performance of shallow junction PMOSFETs fabricated using low-energy ion implantation of B and BF₂ into crystalline and Ge preamorphised silicon

P-channel MOSFETs with source/drain junction depths less than 0.1 mu m were fabricated using 1.35 keV B⁺ and 6 keV BF₂⁺ implantation into crystalline and Ge preamorphised silicon. For 950-1050 degrees C, 10 s rapid thermal annealing, the various implantation conditions yielded similar device characteristics. The implantation of BF₂⁺ resulted in a slight increase in the specific contact resistivity to source and drain over that obtained using B⁺. Measurements of subthreshold I/V characteristics and the channel length dependence of threshold voltage indicated that good long-channel behaviour was obtained for 0.7 mu m channel length devices.