Updated model for UTBB-FDSOI technology is more accurate

The Leti-UTSOI2 was the first available compact model capable of describing and accurately predicting the behaviour of UTBB-FDSOI transistors in all bias configurations, including strong forward bias applied to the back gate of the device. 

Fully Depleted Silicon On Insulator (FDSOI) is a planar process technology that relies on two primary innovations. First, an ultra-thin layer of insulator, called the buried oxide, is positioned on top of the base silicon. Then, a very thin silicon film implements the transistor channel. Thanks to its thinness, there is no need to dope the channel, thus making the transistor fully depleted. The combination of these two innovations is called Ultra-Thin Body and Buried Oxide FDSOI or UTBB-FDSOI.

The Leti-UTSOI2 compact model solution offers designers an essential tool to take full advantage of FD-SOI technology specificities in power consumption and performance optimisation.

The model considerably extends the domain of physical device description compared to other solutions. To provide this feature, Leti used a unique analytical resolution scheme for the calculation of surface potentials at both interfaces of the transistor body, which is valid for all kinds of independent double-gate transistors. From this analytical resolution, Leti has developed the complete model in collaboration with STMicroelectronics, and Leti-UTSOI2 is now used in industrial design kits.

Leti-UTSOI2.1 further improves predictability and accuracy. These improvements include a direct and predictive link between bi-dimensional device electrostatics and process parameters, a refined description of narrow-channel effects, improved accuracy of moderate inversion regime and gate tunnelling current modelling.

Leti-UTSOI2.1 is now available in most of the commercial SPICE and Fast SPICE simulators used by industry.

Thierry Poiroux, Leti Research Engineer and Model Co-developer, will present the new model at the MOS-AK workshop, New version of Leti-UTSOI2 featuring further improved predictability, at 2:30pm on 12^th March, during DATE 2015.

“This new version of the ultra-thin SOI model, which affirms Leti’s continuing leadership in FD-SOI technology, is suitable for designers seeking differentiation in energy management and performance for advanced nodes,” said CEO, Marie-Noëlle Semeria, Leti.