in manufacturing a device using an organic tft , it is essential to develop an element in which a channel length is short or a channel width is narrow to downsize a device . based on the above , it is an object of the present invention to provide an organic tft in which characteristic is improved . in view of the foregoing problem , one feature of the present invention is that an element is baked after an organic semiconductor film is deposited . more specifically , one feature of the present invention is that the organic semiconductor film is heated under atmospheric pressure or under reduced pressure . moreover , a baking process may be carried out in an inert gas atmosphere .