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

Abstract

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 À3 . The doping efficiency is then estimated less than 1% and the possible reason is discussed. Experimental Section Sample PreparationB-doped Si NCs were fabricated using laser crystallization technique. First, a B-doped amorphous Si (a-Si, %10 nm) layer

Triboelectric Charging of Particles, an Ongoing Matter: From the Early Onset of Planet Formation to Assembling Crystals

“…As a consequence, only qualitative data, such as the surface’s polarity, after the tribocharging process can be acquired. It has been attempted by Xu et al to resolve the qualitative KPFM data to calculate the number of charges present on semiconductor surfaces, 21 but for insulators, such methods are unprecedented.…”

Injection and Retention Characterization of Trapped Charges in Electret Films by Electrostatic Force Microscopy and Kelvin Probe Force Microscopy

“…In the past decade, EFM/KPFM has been successfully used to study the injection and retention of trapped charges in inorganic films, [ 16,25,45,46,52–57 ] polymer electrets, [ 47,58–60 ] organic small molecules, [ 42,44 ] the composition of polymer and organic semiconductors, [ 27,41,43 ] nanostructure, [ 48–51,61–78 ] double‐barrier CeO 2 /Si/CeO 2 /Si structures, [ 79 ] DNA molecules, [ 39–80 ] and thin‐film transistors. [ 81–86 ] For example, Heim et al proved that EFM is a useful technique to study the electronic properties of an organic monolayer island at the nanometer scale and found that both carriers are delocalized over the whole island in crystalline monolayer islands, while carriers stay localized at their injection point on a disordered monolayer.…”