Three-interface pseudo-MOSFET models for the characterization of SOI wafers with ultrathin film and BOX

The electrical characterization of unprocessed fully depleted silicon-on-insulator (SOI) layers relies on the pseudo-MOSFET (Ψ-MOSFET) technique. We propose three-interface models which are more appropriate for addressing the case of SOI wafers with ultrathin body and BOX (UTB2). The novel models for threshold voltage and subthreshold swing account for the channel-to-surface and channel-to-substrate coupling which are important effects, respectively, in ultrathin films and thin BOX. The influence of the density of traps at each of the three interfaces (free surface, channel/BOX and BOX/substrate) is discussed. The models are validated with experimental results from a range of SOI film thicknesses.

Graphical abstractThe electrical characterization of unprocessed fully depleted Silicon-on-Insulator (SOI) layers relies on the Pseudo-MOSFET (Ψ-MOSFET) technique. We propose 3-interface models which are more appropriate for addressing the case of SOI wafers with ultrathin body and BOX (UTB2). The novel models for threshold voltage and subthreshold swing account for the channel-to-surface and channel-to-substrate coupling which are important effects, respectively in ultrathin films and thin BOX. The influence of the density of traps at each of the three interfaces (free surface, channel/BOX and BOX/substrate) is discussed. The models are validated with experimental results from a range of SOI film thicknesses.Figure optionsDownload full-size imageDownload as PowerPoint slideResearch highlights► We propose three-interface models appropriate for addressing the case of SOI wafers with ultrathin body and BOX. ► The novel models for threshold voltage and subthreshold swing account for the channel-to-surface and channel-to-substrate coupling. ► The influence of the density of traps at each of the three interfaces (free surface, channel/BOX and BOX/substrate) is discussed. ► The models are validated with experimental results.