A new analytical approach to the low frequency noise analysis in MOSFETs has been developed. Local levels contributing to generation-recombination noise are classified into three groups.For deep levels located near the midgap the approach of zero free carrier concentration inside the space charge region can be used. Simple analytical expressions and conditions of their applicability are derived.Parameters of levels located near the conduction and valence bands can be determined analytically. Analytical expressions for such a situation are also derived. For the intermediate case the level parameters can be only determined numerically. The low frequency noise in nand p-MOSFETs has been studied experimentally at 220 K < T < 425 K over frequency range 2 Hz < f < 10 5 Hz. Experimental noise spectra are analysed on the basis of developed theoretical model.

Low frequency noise and current-voltage measurements in several heavily doped polysilicon resistors of varying geometry and both p and n type, and over a limited range of temperatures from Ϫ60 to 50°C were conducted for the first time. We found that the noise in p-type polysilicon was independent of temperature, but not the n-type polysilicon. For the p-type resistors, linear currentvoltage characteristics were observed, and the relative noise spectral density was independent of bias and inversely proportional to frequency. For the n-type resistors, linear current-voltage characteristics were observed, and the relative noise spectral density was independent of bias. Finally, the normalized noise level in the linear n-type resistors was almost an order of magnitude lower than for the p-type resistors. We believe that this difference is because n-type dopants segregate to the grain boundaries, thus passivating some of the traps there. Boron (p-type dopant͒, on the other hand, does not segregate to the grain boundaries, leaving more unpassivated grain-boundary traps which capture and emit more carriers, resulting in more low frequency noise.

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Messurements are presented of the conduction electron spin resonance linewidths for various samples of lithium and beryllium a t frequencies of 9.27 GHz and 33 and 80 MHz, the samples having dimensions which are large compared with the appropriate skin depth.An increase in the linewidths and certain line shape anomalies as measured a t 9.27 GHz a t low temperatures, are discussed in terms of relaxation in an impure surface layer. A value of xs = 1.6 x c.g.s. units has been deduced for the spin susceptibility of beryllium.On prBsente ici, aux frkquences de 9,27 GHz, de 33 MHz et de 80 MHz, les spectres des rksonances magn6tiqnes klectroniques de divers Bchantillons de lithium et de bBryllium ayant des dimensions qui sont grandes en consideration de la profandeur de la peau. On discute les augmentations de raies, et certaines formes irrkgulibres, observBes B une frbquence de 9,27 GHz et aux tempbratures basses, suivant un mecanisme de relaxation d'une surface impure. On dBduit une valeur de xs = 1,6 x c.g.s. pour la susceptibilite Blectronique de bkryllium.

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