Modeling of low‐frequency noise in advanced CMOS devices

Abstract

The modeling and characterization of low-frequency noise and noise variability in various regimes of operation are investigated for the main advanced complementary metal-oxide semiconductor (CMOS) technologies. Novel materials and innovative device architectures from 0.5 μm to 20 nm gate lengths are studied. The impact of gate stack, realized with ultrathin oxides, polysilicon gate and high-k/metal gate is analyzed. The influence of alternative channel materials, in particular ultrathin body silicon-on-insulator layers, strain Si and III-V materials is addressed. The comparison of low-frequency noise in advanced device architectures, including bulk Si, fully depleted SOI, FinFET, junctionless, and multi-gates structures, is shown. Accurate noise models, taking into account the main physical mechanisms, are proposed for all these very advanced technologies, which will be needed for the nanoelectronics of the next decade.

On the Low-Frequency Noise Characterization of Z2-FET Devices

“…In order to isolate the noise contributions and to determine how the device scaling affects its reliability, Figure 4 extends these considerations to devices featuring different lengths and widths (summarized in Figure 1.d). Figure 4.a reinforces the idea that the devices are mainly affected by large series diode resistance (when the vertical electric field is low): the noise follows the characteristic monotonic slope attributed to a large R S [23], [24], [26] and higher noise levels are observed for narrower devices [27] since R S ∝ 1/W . On the other hand, Figure 4.b corroborates that increasing the frontgate voltage, higher noise levels are observed due to the contribution of interface and gate oxide traps and the higher gate leakage current.…”

“…N in and N S are the effective charge number of carriers and α in and α S are the Hooge constants. The term 4KT /R t models the thermal noise of the resistances, 2q/I the normalized contribution of the shot noise associated with carrier injection through the p − n junctions [17] and S 1/f I 2 the contribution of the surface noise mechanisms which follows a 1/f trend in frequency domain [20], [26], [29]. This latter contribution can be seen as the sum of the fluctuation in the number of carriers (trapping and detrapping) at the interface and oxide gate traps and an additional term regarding the gate leakage noise contribution [24], as the previous analyses of Figure 3.c and 3.d have suggested.…”

Low-frequency noise in downscaled silicon transistors: Trends, theory and practice

“…Third, the lowfrequency noise in MOS transistors is higher than the noise in BJTs, as one can see in Figure 15. In this figure, the data are for 134 nMOS transistors from [22,47,48,49,50,51,72,86,87,88,89,90,91,92,93,94,95,96,97,98,99,100,101,102,103,104,105,106,107,108,109,110,111,112,113,114,115,116,117,118,119,120,121,122,123], and for 53 pMOS transistors from [47,52,86,…”

“…, when the trap is in the middle of the oxide. (113) To illustrate the impact of tunneling to the gate, we assume a conservative high value for τ o =10 -8 s (see after eq. ( 99)) and plot in Figure 23b the evolution of tunneling time constant τ with the position of the trap in the oxide for several cases relevant to current research of physical oxide thicknesses t ox =3, 4 and 5 nm and λ=0.1nm and 0.21 nm for silicon and hafnium oxides, respectively.…”

“…Input-referred voltage noise S V G (gate voltage 1/f noise at 1Hz) in silicon MOS transistors compared to the corresponding S V B in silicon npn BJTs. ( ) for nMOS transistors from[22,47,48,49,50,51,72,82,86,87,88,89,90,91,92,93,94,95,96,97,98,99,100,101,102,103,104,105,106,107,108,109,110,111,112,113,114,115,116,117,118,119,120,121,122,123], ( ) for pMOS transistors from[47,52,…”