FinFETs are next generation transistors, which utilize multi-gate structure.
In FinFET as the gate electrode wraps the channel from all three sides to give better electrostatic control of the channel.FinFETs have the following advantages over bulk MOSFETs: · Power consumption- Very less leakage and parasitic current leading to less static power.· Operating Voltage- FinFETs operate at a lower voltage as a result of their lower threshold voltage. · No Short channel effect- Excellent electrostatic control of the channel 15.· No Body effects in FinFETs when compared to planar CMOS.· The realization of self-aligned double-gate devices in FinFET with a conventional CMOS process is attractive 7.
E. Manufacturing Challenges of FinFET TechnologyTransition from planar structure to FinFET involves many manufacturing challenges. Especially with respect to Pattering and formation of the fins demands a tighter control on manufacturing and processing steps 10.
Below are the some of the manufacturing challenges in realizing FinFETs. · Fin ShapeFirst Finfet-based high performance complex logic product was Intel’s 22nm node microprocessor. It has been built with finfet sidewalls sloping at about 8 degrees from vertical. Such shape has several practical advantages for manufacturability of this technology 18:- Fins with lower aspect ratio (height : width) are more mechanically sturdy thus less vulnerable to damage during manufacturing process;- Sloping sidewalls assure better fill of trenches between fins with fin isolation dielectric;- Etching gate spacer off fin sidewalls is easier than for vertical fins;- Gate etch, which in finfets requires much more overetch, is easier;- Doping of source and drain extensions by implantation is easier as sloped sidewalls are more suitable for dopant placement by vertical or low angle tilt implants.
