Why Is Oxide-Trap Charge-Pumping Method Appropriate for Radiation-Induced Trap Depiction in MOSFET?

摘要

Radiation-induced traps, which are generally identified using specific extraction methods, play an important role in the reliability of MOS devices. In this paper, the oxide-trap-based-on-charge-pumping (OTCP) method is used to estimate radiation-induced oxide, interface, and border traps in complementary N- and P-MOS transistors. We emphasize on the critical comparison between the OTCP and classical methods like subthreshold slope (STS), midgap (MG), capacitance–voltage $(CV)$, dual-transistor CP (DTCP), and DT border trap (DTBT), giving a clear insight on the benefits and limitations of OTCP. According to experimental data, the OTCP method is often more accurate than the classical methods. On one side, OTCP offers more accurate densities of radiation-induced interface traps $(Delta N_{rm it})$ and border traps $(Delta N_{rm bt})$, while STS and MG overestimate $Delta N_{rm it}$ because both interface and border traps are sensed like interface traps. On the other side, OTCP estimates $Delta N_{rm it}$, $Delta N_{rm bt}$, and oxide trap $(Delta N_{rm ot})$ for N- and P-MOSFETs separately, while DTCP and DTBT give average densities for whole N- and P-MOS devices. Finally, $Delta N_{rm ot}$ obtained by OTCP is in excellent agreement with that given by $CV$. However, they show a slight discrepancy in the $D-n-nelta N_{rm it}$ extraction.