Title :
Advances in 3D CMOS sequential integration
Author :
Batude, P. ; Vinet, M. ; Pouydebasque, A. ; Le Royer, Cyrille ; Previtali, B. ; Tabone, C. ; Hartmann, J.-M. ; Sanchez, L. ; Baud, L. ; Carron, V. ; Toffoli, A. ; Allain, F. ; Mazzocchi, V. ; Lafond, D. ; Thomas, O. ; Cueto, O. ; Bouzaida, N. ; Fleury, D.
Author_Institution :
CEA, MINATEC, Grenoble, France
Abstract :
For the first time 3D sequential CMOS integration turns up to be an actual competitor for sub 22nm technology nodes. Thanks to the original use of molecular bonding, high quality top Si active layers are obtained. Thermally robust bottom salicide goes through the whole top FET processing without any significant sheet resistance degradation. The low temperature integration of raised source and drain for top layers is demonstrated. A decrease by 4¿ of the Equivalent Oxide Thickness is measured when a low thermal budget process is implemented. The electrostatic coupling between stacked FETs is demonstrated thanks to an ultra thin inter layer dielectric thickness of 60nm. It leads to a threshold voltage dynamic shift of 130mV enabling SRAM stabilization.
Keywords :
CMOS integrated circuits; SRAM chips; field effect transistors; sequential circuits; 3D CMOS sequential integration; FET; SRAM stabilization; electrostatic coupling; equivalent oxide thickness; molecular bonding; sheet resistance degradation; size 60 nm; thermally robust bottom salicide; threshold voltage dynamic shift; ultra thin inter layer dielectric thickness; voltage 130 mV; Bonding; CMOS technology; Dielectric measurements; Electrical resistance measurement; Electrostatic measurements; FETs; Robustness; Temperature; Thermal degradation; Thermal resistance;
Conference_Titel :
Electron Devices Meeting (IEDM), 2009 IEEE International
Conference_Location :
Baltimore, MD
Print_ISBN :
978-1-4244-5639-0
Electronic_ISBN :
978-1-4244-5640-6
DOI :
10.1109/IEDM.2009.5424352