Characterization and modeling of low-frequency noise and random telegraph noise in advanced CMOS imaging technologies

Defense of doctoral thesis by Owen GAUTHIER, for the  University  Grenoble Alpes, speciality  " NANO ELECTRONIC & NANO TECHNOLOGIES "

Abstract :
Following the reduction of the size of CMOS transistors, the low-frequency noise due to the trapping/detrapping of charge carriers in the gate dielectric becomes more and more important. It is indeed inversely proportional to the gate oxide surface. This also leads to a strong increase in dynamic variability, increasingly disrupts the operation of electrical circuits and reduces the design margin of the circuits. This is particularly the case for readout circuits in imaging applications, especially for low illumination where noise limits the sensitivity of the sensor. For small size transistors, this noise variability also results in a specific noise called 'Random Telegraph Noise' (RTN) which has specific temporal and frequency properties. The purpose of this thesis will be the characterization and modeling of this noise in imaging technologies. Thus, the thesis will be devoted initially to the experimental study of RTN noise as a function of geometric parameters, polarization (Vgs, Vds) and temperature. This will allow to cover the whole field of use of the MOS transistor. The search and extraction of the RTN noise parameters is not an easy task, especially when there are several RTN events overlapping. For this purpose, different extraction methods (based on histograms, Time-Lag-Plot or Markov chains) will be evaluated to identify a reliable and automatable extraction method. New extraction methods could also be developed, if necessary. Finally, a model of this noise will be proposed for a possible implementation in a simulator.

Jury members:

• Quentin RAFHAY, Assistant professor  HDR, Grenoble INP - UGA, CROMA : Supervisor
• Christoforos THEODOROU, Researcher CNRS, CROMA : Co-supervisor
• Sébastien HAENDLER, Engineer , STMicroelectronics : Co-supervisor, industriel supervisor
• Fabien PASCAL, Professor of universities, University of Montpellier, IES : Reviewer
• Matthias BUCHER, Professor, School of Electrical and Computer Engineering Technical University of Crete : Reviewer
• Giorgio DI NATALE, Research director CNRS, TIMA : Examiner, Chairman of the jury
• Irina IONICA, Assistant professor HDR, Grenoble INP - UGA, CROMA :Examiner, UGA Representative