Formation of surface-induced nanopattern (SINPAT) in ultrathin diblock copo
lymer films is studied by scanning force microscopy and Monte Carlo simulat
ion. The pattern is caused by strong adsorption of one of the two blocks fo
rming a quasi-two-dimensional coil while the other block dewets this adsorp
tion layer. Scanning force microscopy allowed to observe an order-disorder
transition for a SINPAT film of polystyrene-block-poly(2-vinylpyridine) on
mica when the length of the dewetting polystyrene block was varied. The exp
erimental data are compared with the Monte Carlo simulations which demonstr
ate how the pattern formation depends on the degree of polymerization of th
e dewetting block and the unfavorable interaction potential between the dif
ferent components.