1/f noise in ohmic silicon JFET channels

Abstract

Measurements have been made of the excess noise in silicon. The specimens were ohmic, uniform cross-section JFET channels with no active oxide interfaces. The gate voltage was used to deplete the channel and change one transverse linear dimension. The temperature was varied between 77K and 368K to change the dominant scattering mechanism. The carrier density and mobility profiles across the channel were measured. At low temperatures one excess noise component was identified as due to donor occupation fluctuation. The observed excess noise component with a 1/f spectrum has been compared with the predictions of various models. The magnitude of the noise and its dependence on the scattering mechanism do not agree with the mobility fluctuation model.

Electrical Stability and Flicker Noise of Thin-Film Heterojunction FETs on Poly-Si Substrates

“…In contrast to MOSFETs, JFETs have been rarely studied, but it is known that the flicker noise behavior of JFETs is generally the same as MOSFETs [58]. It is also known that properly designed JFETs can achieve extremely low flicker noise [59]- [62]. For appropriate bench-marking, first-order expressions for HJFET flicker noise are derived in a form suitable for direct comparison with conventional TFTs, as described below.…”