SEMINAR, Wednesday, 3 May, 12:00, Sala d'Actes Pepe Millán del CNM
“Generation-recombination noise in advanced CMOS and memory devices” Prof. Eddy Simoen Interuniversity Microelectronic Center, IMEC, Leuven, Belgium
Abstract: Generation-Recombination (GR) noise is one of the excess noise sources in semiconductor materials and devices, which originates from successive capture and emission events by a deep-level GR center. The corresponding spectrum is Lorentzian, with a plateau at low frequencies and a 1/f2 roll of beyond the corner frequency fc. In MOSFETs, at least two types of GR noise can be distinguished: the first type has a corner frequency that does not chance with gate bias, while for the second case, there is a pronounced dependence. It is believed that the first type of GR centers resides in the depletion region, while oxide traps originate the second type of spectra. They are better known as Random Telegraph Noise (RTN).
In the seminar, it will be outlined how in both cases information can be gathered regarding the deep level parameters. For depletion region traps, studying fc as a function of temperature allows performing GR noise spectroscopy, which leads to the identification of several processing-induced defects in Fully Depleted Silicon-on-Insulator (FDSOI) nMOSFETs, Ge pMOSFETs and InGaAs nMOSFETs. In the case of RTN, there are several ways to derive information on the underlying oxide trap parameters. This can be based on time- or frequency domain studies. In scaled devices, RTN can be generated by defects in the gate oxide or in the semiconductor. As an example, different types of RTN in vertical polysilicon nMOSFETs for Non-Volatile Memories will be discussed. It will be outlined how information on the trap location along ad in the channel can be derived.
Eddy Simoen is a senior researcher at imec since 1986 and a part-time Guest Professor at Ghent University since 2012. He is a Fellow of the ECS since 2016 and the current Chair of the IEEE Electron Devices Society (EDS) of the Benelux. His field of research covers the impact of defects on semiconductor materials and device performance, low-frequency noise and Deep-Level Transient Spectroscopy of semiconductors. He has published over 1600 technical papers and conference contributions and 5 books and several book chapters.