Simulation of total ionizing dose and random dopant fluctuations in sub-100 nm transistor nodes

Abstract

Finite Elements Method simulations of Total Ionizing Dose in two state-of-the-art transistor nodes are presented: The 45 nm Partially-Depleted Silicon-on-Insulator MOSFET and the 22 nm bulk FinFET. A systematic method has been developed to study charge trapping in field isolation oxides using the simulation software Sentaurus device. The method is based on solving transport equations for carriers in the oxide. Aspects of simulation of interface trap formation through de-passivation from ionic hydrogen are discussed. This includes transport of hydrogen species in the device and state transitions. Calibration of the trapping model is performed using experimental results on Buried OXide irradiated capacitors of 400 nm SiO₂. The extracted parameters are then used in the two FET technologies examined. In both cases, increased radiation hardness of the devices, tested using the bulk traps method, up to total doses of 600 KRad(SiO₂) in the case of the PDSOI and 1 MRad(SiO₂) in the case of the FinFET is shown. In the 45nm node, Random Dopant Fluctuations (RDFs) using the Sano and the Impedance Field Method are examined in combination with charge introduced in the field oxide regions. RDFs are shown to have a significant effect in the sub-threshold characteristics of the irradiated devices during the weak inversion of the parasitic transistor induced in the device. Their effect is negligible, however, when the parasitic channel is fully formed.

More information

Identifiers

ORCID for Eleni Chatzikyriakou: orcid.org/0000-0002-5624-3701

ORCID for Cornelis De Groot: orcid.org/0000-0002-3850-7101

Catalogue record

Export record