Methodology to separate channel conductions of two level vertically stacked SOI nanowire MOSFETs

• Published in: Solid-state electronics Vol. 149; pp. 62 - 70
• Main Authors: Paz, Bruna Cardoso, Cassé, Mikaël, Barraud, Sylvain, Reimbold, Gilles, Vinet, Maud, Faynot, Olivier, Pavanello, Marcelo Antonio
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01-11-2018; Elsevier
• Subjects: Back gate bias; Engineering Sciences; Micro and nanotechnologies; Microelectronics; Mobility; SOI; Temperature; Tridimensional numerical simulations; Vertically stacked nanowires; Mobility; Temperature; SOI; Tridimensional numerical simulations; Back gate bias; Vertically stacked nanowires; temperature; back gate bias; mobility; tridimensional numerical simulations; vertically stacked nanowires
• ISSN: 0038-1101; 1879-2405
• DOI: 10.1016/j.sse.2018.08.012

•A methodology is proposed to separate mobility of each level of stacked NW structure.•Lower low filed mobility is obtained for top GAA level comparing to Ω bottom NW.•Mobility varies with VB due to holes concentration reduction and displacement.•A linear behavior between mobility and back bias has been evidenced.•Mobility dependence on temperature remarkably varies with VB for Ω-NWs.
This work proposes a new method for dissociating both channel conductions of two levels vertically stacked inversion mode nanowires (NWs) composed by a Gate-All-Around (GAA) level on top of an Ω-gate level. The proposed methodology is based on experimental measurements of the total drain current (IDS) varying the back gate bias (VB), aiming the extraction of carriers’ mobility of each level separately. The methodology consists of three main steps and accounts for VB influence on mobility. The behavior of non-stacked Ω-gate NWs are also discussed varying VB through experimental measurements and tridimensional numerical simulations in order to sustain proposed expressions of mobility dependence on VB for the bottom level of the stacked structure. Lower mobility was obtained for GAA in comparison to Ω-gate. The procedure was validated for a wide range of VB and up to 150 °C. Similar temperature dependence of mobility was observed for both Ω-gate and GAA levels.