Comprising a first step of supporting a substrate formed with a scintillator on at least three protrusions of a target-support element disposed on a vapor deposition table so as to keep a distance from said vapor deposition table; a second step of introducing said vapor deposition table having said substrate supported by said target-support element into a vapor deposition chamber of a CVD apparatus; and a third step of depositing an organic film by CVD method onto all surfaces of said substrate, provided with said scintillator, introduced into said vapor deposition chamber.