Title :
Trap Generation in IL and HK layers during BTI / TDDB stress in scaled HKMG N and P MOSFETs
Author :
Mukhopadhyay, Saibal ; Joshi, Kishor ; Chaudhary, Varun ; Goel, Nishith ; De, Suvranu ; Pandey, Rajan K. ; Murali, Kota V. R. M. ; Mahapatra, Santanu
Author_Institution :
Dept. of Electr. Eng., IIT Bombay, Mumbai, India
Abstract :
Independent Trap Generation (TG) monitors such as DCIV and SILC have been used during NBTI, PBTI (and TDDB) stress in differently processed HKMG devices. TG from DCIV for NBTI is attributed to Si/IL and IL/HK interfaces; TG from DCIV for PBTI to IL/HK interface but at similar energy location as NBTI. TG from DCIV shows similar stress bias (VG,STR), time (tSTR) and temperature (T) dependence for NBTI and PBTI, while TG for PBTI from SILC shows very different dependence as it likely scans TG at different spatial and energetic locations. TG contribution to VT shift (ΔVT) is compared to ΔVT from ultra-fast measurements. A compact model is used to predict overall BTI ΔVT considering uncorrelated contributions from independently measured TG and trapping (TP) in pre-existing and generated bulk traps. Impact of IL scaling on BTI and its underlying subcomponents are studied. Physical origins of different TG and TP processes have been identified using Density Functional Theory (DFT) simulations.
Keywords :
MOSFET; density functional theory; electric breakdown; electron traps; high-k dielectric thin films; leakage currents; silicon compounds; BTI-TDDB stress; DCIV; DFT simulations; HK layers; IL layers; IL-HK interfaces; N-and-P MOSFET; NBTI stress; PBTI stress; SILC; Si; Si-IL interfaces; TG; bulk traps; density functional theory simulations; dependent dielectric breakdown; energetic locations; high-k metal gate; interlayer quality; negative-and-positive bias temperature instability; scaled HKMG device; spatial locations; stress bias; stress induced leakage current; trap generation; ultra-fast measurements; uncorrelated contributions; Current measurement; Delays; Silicon; Stress; Stress measurement; Temperature measurement; DCIV; DFT simulation; IL Scaling; NBTI; Ov defects; PBTI; SILC; UFM-MSM; trap generation; trapping;
Conference_Titel :
Reliability Physics Symposium, 2014 IEEE International
Conference_Location :
Waikoloa, HI
DOI :
10.1109/IRPS.2014.6861146
