Electrical reliability aspects of through the gate implanted MOS structures with thin oxides

The effect of through the gate implantation (TGI) on MOS devices with oxide thicknesses of 3.3, 4.0, and 20 nit is studied, utilizing constant voltage stress tests and a substrate hot electron (SHE) injection technique. For 3 .3 and 4.0 nm thick oxides, a dependence of time to breakdown on TGI dose i s detected which, for 3.3 nm samples, diminishes with increasing test volta ge. SHE injection measurements show a TGI induced increase in intrinsic ele ctron trap density and also an increase in trap generation rate during samp le stressing. A change of electron trap generation dynamics seems to be the main cause for oxide weakening due to TGI. (C) 2001 Elsevier Science Ltd. All rights reserved.