Ion-beam-induced epitaxial crystallization (IBIEC) and solid phase epitaxial growth (SPEG) of Si_1-xC_x layers in Si fabricated by C ion implantation

Amorphous Si_1-xC_x layers in Si(100) (0.013 ≤ x ≤ 0.032 at peak concentration) formed by 35 keV ¹²C implantation were crystallized by solid phase epitaxial growth (SPEG) up to 850°C and by ion-beam-induced epitaxial crystallization (IBIEC) with 400 keV Ar or Ge ions at 300-400°C. SPEG process has induced the epitaxial growth up to the surface for samples with x ≤ 0.019 and IBIEC process has induced that for samples with x ≤ 0.025. Rutherford backscattering spectrometry (RBS) measurements have revealed a direct scattering peak due to extended defects around the depth of peak C concentration both in SPEG-grown samples (x = 0.019) and IBIEC-grown sample (x = 0.025). X-ray diffraction (XRD) has shown a growth with smaller tensile strain in both SPEG- and IBIEC-grown samples than in fully strained layers. Photoluminescence (PL) measurements at 2 K have shown a strong I_l line emission in IBIEC-grown samples, which can be attributed to vacancy clustering. The local configuration of defects around C atoms in the IBIEC-grown samples is thought to be an origin of the smaller tensile strain.