LOW FREQUENCY NOISE DEGRADATION IN ULTRA-THIN OXIDE (15Å) ANALOG n-MOSFETS RESULTING FROM VALENCE-BAND TUNNELING
نویسندگان
چکیده
Abnormal increase of low frequency flicker noise in analog nMOSFETs with gate oxide in valence band tunneling domain is investigated. In 15Å oxide devices, valence-band electron tunneling from Si substrate to poly-gate occurs at a positive gate voltage and results in the splitting of electron and hole quasi Fermi-levels in the channel. The excess low frequency noise is attributed to electron and hole recombination at interface traps between the two quasi Fermilevels. The trap capture and emission times in valence band tunneling domain are extracted from random telegraph signal. The dependence of measured trap times on gate voltage is consistent with our proposed model. [
منابع مشابه
Evidence for a “linear kink effect” in ultra- thin gate oxide SOI n-MOSFETs
Introduction An excess of the drain current ID, related to the floating body effect and hole generation by impact ionization, can appear in the saturation region of SOI MOSFETs [1]. This mechanism has been reported for drain voltages below the band-gap voltage (VD=0.7 V) by including additional energy gain mechanisms to overcome the thresholds of impact ionization processes [2,3]. In this paper...
متن کاملDesign of an S-band Ultra-low-noise Amplifier with Frequency Band Switching Capability
In this paper, an ultra-low-noise amplifier with frequency band switching capability is designed, simulated and fabricated. The two frequency ranges of this amplifier consist of the 2.4 to 2.5 GHz and 3.1 GHz to 3.15 GHz frequency bands. The designed amplifier has a noise figure of less than 1dB, a minimum gain of 23 dB and a VSWR of less than 2 in the whole frequency band. The design process s...
متن کاملA review of gate tunneling current in MOS devices
Gate current in metal–oxide–semiconductor (MOS) devices, caused by carriers tunneling through a classically forbidden energy barrier, is studied in this paper. The physical mechanisms of tunneling in an MOS structure are reviewed, along with the particularities of tunneling in modern MOS transistors, including effects such as direct tunneling, polysilicon depletion, hole tunneling and valence b...
متن کاملLow frequency gate noise modeling of ultrathin Oxide MOSFETs
An analytical model for 1/f gate noise is developed and applied to the simulation and the characterization of ultra-thin MOSFETs. The proposed model is based on oxide trapping mechanisms and uses the concept of equivalent flat band voltage fluctuations. The developed model reproduces experimental behaviors. The power spectral density of flat band voltage fluctuation extracted from gate current ...
متن کاملSimulation of Oxide Trapping Noise in Submicron n-Channel MOSFETs
Carrier trapping via tunneling into the gate oxide was implemented into a partial differential equation -based semiconductor device simulator to analyze the -like noise in silicon MOSFETs. Local noise sources are calculated using the carrier tunneling rates between trap centers in the oxide and those at the interface. Using the Green’s transfer function approach, noise contributions from each n...
متن کامل