Nanoscale Characterization of Active Doping Concentration in Boron‐Doped Individual Si Nanocrystals

Doping of Si nanocrystals (NCs) is essential to the photonic and photovoltaic applications. In this work, individual Si NCs on Si substrate are prepared by excimer laser crystallization technique. The doping effect of boron (B) atoms is characterized at the nanoscale by Kelvin probe force microscopy (KPFM) measurement. The KPFM signal of B‐doped Si NCs is found opposite to that of intrinsic counterparts, indicating that active B doping is obtained. Moreover, the surface potential is reconstructed from KPFM images by Green's electrostatic theorem and deconvolution processing, and accordingly the active doping concentration is calculated around 10 17 –10 18 cm −3 . The doping efficiency is then estimated less than 1% and the possible reason is discussed.