摘要
The surface quality of the substrate is a crucial factor in building ＂clean＂ quantum-dimensional systems. There are a number of micro-nano metric methods for the analysis state of surface： the atomic force microscopy, the scanning tunneling microscopy and others. The SE （surface electron） over substrate has a ＂soft＂ hydrogen-like spectrum in the normal direction and the SEs mobility along is sensitive to the inhomogeneities of the substrate and this is analyzed in work. The values of electron mobility and energy of thermal activation are basic parameters of transport process which essentially depend on the helium film thickness. For analysis of nano-size inhomogeneities of substrate here we apply a new method providing a uniformity of the film thickness on substrate and fixing of measuring cell with supply wires. The plunger with electro-mechanic driver into a hermetic chamber is used for variation the helium level and consequently the film thickness. Considering values the conductivity and the variation of potential along surface is estimated the effective size of roughness from several nanometers （for non-saturated helium film） to 10^2 nm （for saturated film）.
