Carbon rich silicon (Si1-yCy)for defect engineering of ion implantation damage in devices activated by solid phase epitaxy

Abstract

The suitability of using epitaxially incorporated carbon in silicon to suppress implantation end-of-range (EOR) defects in devices (e.g., nMOSFETs) activated by solid phase epitaxial regrowth (SPER) has been examined. An effective elimination of EOR defects is achievable with a carbon content of the impurity concentration (~0.08%) under an SPER annealing at a temperature as low as 650 A?C. Junction leakage suppression by ~2-8 times has been obtained in carbon incorporated SPER devices. A prolonged SPER annealing of 10 minutes further reduces the junction leakage current, by ~60 times, indicating the strong dependence on the annealing time. Extracted activation energy (Ea) of ~1.1 eV from the junction leakages annealed at various temperatures conforms well to the Ea of diffusivity of interstitial carbon (IC), supporting the notion of an IC induced leakage. MOSFET devices with carbon incorporation have revealed a current voltage behavior which remains comparable to a pure silicon MOSFET when the carbon layer is correctly optimized, indicating the possibility of carbon incorporation for device fabrication