As it was predicted theoretically by Andreev at zero temperature for dilute 3He in 4He mixtures, 3He atoms will form a 2D Fermi liquid at liquid helium surface. Direct experimental observation of a 3He nano-layer on the surface of a weak 3He/4He mixture has not been achieved, and today no information is available about the distribution of 3He near the helium surface. In our earlier experiments (RB1010049 and RB1120146) we have shown that at low temperature reflectometry data demonstrate accumulation of 3He atoms near liquid helium surface. However we failed to analyse the data analytically by comparison with neutron reflection model because of significant optical distortions caused by liquid He meniscus. Here we propose experiment which will allow us to eliminate meniscus effect. In this set-up we will produce ~ 1000A superfluid helium film on atomically smooth silicon wafer.