Thin body silicon-on-insulator N-MOSFET with silicon-carbon source/drain regions for performance enhancement

We report a novel strained n-channel transistor structure featuring silicon-carbon (SiC) source and drain (S/D) regions formed on thin body SOI substrate. The SiC material is pseudomorphically grown by selective epitaxy and the carbon mole fraction incorporated is 1%. Lattice mismatch between SiC and Si results in uniaxial tensile strain in the Si channel region which contributes favorably to electron mobility enhancement. Drive current I_Dsat enhancement of 25% was observed for 90 nm gate length L_G transistors, and I_Dsat enhancement of up to 35% was observed at L_G of 70 nm. In addition, drive current enhancement shows dependence on device width and channel orientation. All transistors were formed on (001) SOI substrates. The largest I_Dsat enhancement is observed for transistors with the [010] channel orientation