Negative bias temperature stress on low voltage p-channel DMOS transistors and the role of nitrogen

Negative bias temperature instabilities in sequentially stressed and annealed p-channel power VDMOSFETs

“…1, reveal the threshold voltage shifts observed during the stressing with À40 V and +40 V at 150°C. As can be seen, NBT stressing caused significant V T shifts, while the shifts found during PBT stressing were almost negligible, which is in line with a number of other studies [1][2][3]7,8].…”

“…3 and 4 do not indicate the one-to-one correspondence between the decrease in DN ot and increase in DN it , implying that portion of O 3 "Si +Å Si"O 3 near-interface defects is simply neutralized by electrons without participating in reaction (7). Besides, the H 2 molecules released in reaction (8) may diffuse into the oxide to be cracked at positively charged traps through inverse reaction (6) [12], neutralizing the traps and creating additional H + ions for reaction (8). However, as the annealing progresses and DN it exceeds DN ot , the occurrences of both reactions (7) and (8) become less likely so DN ot tends to saturate, while DN it starts even slowly to decrease, which probably means that H Å atoms and H 2 molecules released in reactions (7) and (8) begin to passivate interface traps through the inverse reactions (2) and (3).…”

“…Degradation of power MOSFETs under various stresses (irradiation, high field, temperature, and hot carrier injection) has been subject of extensive research [5,6], but only few authors seem to have addressed the NBTI in these devices [7][8][9][10]. Increased gate oxide fields and elevated temperatures are typically found in burn-in tests [11], but can be approached during routine operation of power MOSFET in automotive and industrial applications as well [8].…”

Influence of Ionizing Radiation and Hot Carrier Injection on Metal-Oxide-Semiconductor Transistors

“…Due to their favourable electric characteristics (great operative speed, low switchon resistance, high switching voltage, etc. ), the VDMOS transistors have found their application in the fields such as automotive industry [5]. Switching characteristics of VDMOS transistors at high frequencies (higher than 100 kHz [6]) have also proved very good owing to which these transistors are applied as switching components for highfrequency sources of supply used in medical electronics, engine control systems, switching sources of supply in telecommunication researches, etc.…”

Implications of Negative Bias Temperature Instability in Power MOS Transistors

“…Degradation of power MOSFETs under various stresses (irradiation, high field, and hot carriers) has been subject of extensive research (see e.g. and references cited therein), but very few authors seem to have addressed the NBTI in these devices (Demesmaeker et al, 1997;Gamerith & Polzl, 2002;Stojadinović et al, 2005;Danković et al, 2007;, Manić et al, 2009). However, power devices are routinely operated at high current and voltage levels, which lead to both self heating and increased gate oxide fields, and thus favour NBTI.…”