Determination of the conduction band offset between hydrogenated amorphous silicon and crystalline silicon from surface inversion layer conductance measurements

The presence of an electron rich inversion layer in $p$-type crystalline silicon $(c-Si)$ at the interface with $n$-type hydrogenated amorphous silicon $(a-Si:H)$ is experimentally demonstrated from the coplanar conductance of $(n)$ $a-Si:H∕(p)$ $c-Si$ structures, which is shown to be very sensitive to the band mismatch between the two semiconductors. The temperature dependence of the corresponding sheet electron density allows to determine with a very good precision the conduction band offset $ΔEC$ between $a-Si:H$ and $c-Si:ΔEC=0.15±0.04eV$⁠.