To provide a fluorinated compound, which can readily form a thin film having a hydrophobic/hydrophilic pattern, by employing an ultraviolet light having a relatively low energy.A thin film having a hydrophobic/hydrophilic pattern is formed by irradiating a thin film formed by employing a fluorinated compound represented by the following formula 1 (in the formula 1, each of R.sup.1, R.sup.2, R.sup.3 and R.sup.4 which are independent of one another, is a hydrogen atom, a halogen atom or a monovalent organic group, provided that at least one of them is a monovalent organic group having fluorine atoms, and R.sup.5 is a hydrogen atom or a monovalent organic group, R.sup.6 is a monovalent organic group, and A is a hetero atom) with ultraviolet light ##STR00001##