Guidelines for reverse short-channel behavior

Necessary conditions for the occurrence of the reverse short-channel (RSC) effect for threshold voltage V/sub T/ for submicrometer MOSFETs due to channel profile nonuniformity are established: (1) sufficiently large concentration decrease towards the Si-SiO/sub 2/ interface of the channel doping (not necessarily a peak below the surface); (2) laterally nonhomogeneous enhancement of the diffusivity of the channel dopant either by injection of interstitials or vacancies from outside the gate region; and (3) the minimal distance between the point-defect injection next to the gate and the metallurgical channel-to-drain junction is smaller than the characteristic lateral decay length of the point defects. The above conditions are corroborated by the conditions for the threshold-voltage enhancement at the small channel lengths reported.<
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