Low-frequency noise sources in polysilicon emitter BJT's: influence of hot-electron-induced degradation and post-stress recovery

Low-frequency noise of the structures with Ge-nanoclusters of rather high surface density grown on the oxidized silicon surface is investigated for the first time. It was revealed that the 1/f γ noise, where γ is close to unity, is the typical noise component. Nevertheless, the 1/f γ noise sources were found to be distributed nonuniformly upon the oxidized silicon structure with Ge-nanoclusters. The noise features revealed were analyzed in the framework of widely used noise models. However, the models used appeared to be unsuitable to explain the noise behavior of the structures studied. The physical processes that should be allowed for to develop the appropriate noise model are discussed.

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LES Predictions of Jet Noise for a Pylon-Mounted Dual Stream Nozzle and Jet Surface Interactions

Volume 2A: Turbomachinery ◽

10.1115/gt2016-58175 ◽

2016 ◽

Cited By ~ 2

Author(s):

P. Vogel ◽

J. Bin ◽

N. Sinha

Keyword(s):

Supersonic Jet ◽

Low Frequency ◽

Frequency Noise ◽

Low Frequency Noise ◽

Acoustic Source ◽

Noise Sources ◽

Surface Time ◽

Acoustic Source Localization ◽

Jet Nozzle ◽

Field Noise

An end-to-end LES/FW-H noise prediction model has been demonstrated and validated with acoustic and flowfield data from a dual stream nozzle with pylon experiment conducted at NASA GRC using their Jet Engine Simulator (JES) geometry. Results show a large region of high turbulent kinetic energy (TKE) in the wake of the pylon. Acoustic Source Localization (ASL) studies using our numerical phased array methodology show this wake region to be the principle location of low frequency noise sources while higher frequency sources occur nearer to the nozzle lips. Numerical simulations have also been conducted on Jet-Surface Interaction (JSI) effects of a supersonic jet exhausting parallel to a finite surface. Time-averaged LES data and far-field noise predictions have been obtained for multiple surface locations as well as for an isolated jet nozzle. For upstream observers located below the surface, results show an increase in low-frequency noise over what was predicted for the isolated nozzle due to JSI effects and decrease in high-frequency noise due to shielding. This was significantly more pronounced for an over-expanded jet than for an under-expanded jet, an effect that was primarily attributed to the shorter core length of the over-expanded jet.

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Crowding effects and low frequency noise in polysilicon emitter bipolar transistors

Solid-State Electronics ◽

10.1016/s0038-1101(99)00008-8 ◽

1999 ◽

Vol 43 (5) ◽

pp. 931-936 ◽

Cited By ~ 2

Author(s):

Jean-Marc Routoure ◽

Jacques Lepaisant ◽

Daniel Bloyet ◽

Serge Bardy ◽

Jacques Lebailly

Keyword(s):

Low Frequency ◽

Bipolar Transistors ◽

Frequency Noise ◽

Low Frequency Noise ◽

Crowding Effects ◽

Polysilicon Emitter

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Low Frequency Noise Analysis in Advanced CMOS Devices

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.324.441 ◽

2011 ◽

Vol 324 ◽

pp. 441-444 ◽

Cited By ~ 6

Author(s):

Jalal Jomaah ◽

Majida Fadlallah ◽

Gerard Ghibaudo

Keyword(s):

Experimental Data ◽

Noise Analysis ◽

Low Frequency ◽

Deep Submicron ◽

Electrical Noise ◽

Frequency Noise ◽

Low Frequency Noise ◽

Noise Sources ◽

The Impact ◽

Mobility Fluctuations

A review of recent results concerning the low frequency noise in modern CMOS devices is given. The approaches such as the carrier number and the Hooge mobility fluctuations used for the analysis of the noise sources are illustrated through experimental data obtained on advanced CMOS generations. Furthermore, the impact on the electrical noise of the shrinking of CMOS devices in the deep submicron range is also shown.

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