A New Liner Stressor with Very High Intrinsic Stress (≫ 6 GPa) and Low Permittivity Comprising Diamond-Like Carbon (DLC) for Strained P-Channel Transistors

We report a new liner stressor comprising a diamond-like carbon (DLC) layer with very high intrinsic stress for boosting the performance of p-channel transistors. A record-high intrinsic compressive stress of more than 6 GPa is demonstrated, well exceeding values currently achievable with the conventional SiN contact etch-stop layer (CESL). Two major advantages of the DLC layer are lower permittivity and significantly higher compressive stress, therefore enabling further pitch and density scaling with less performance compromise. We integrated the DLC liner stressor with nanoscale SOI p-FETs, demonstrating significant drive current I_D,sat enhancement of up to 58% over control devices without liner stressor.