a lithography system having a resist coating and developing apparatus a wafer transferring mechanism and an exposure control apparatus the exposure control method in the lithography system includes the steps of transmitting data of temperature for heat treating a resist film in the resist coating and developing apparatus to the exposure control apparatus determining and controlling exposure time based on the temperature data and exposing the resist film on a wafer which is moved or transferred by the wafer transferring mechanism during the determined exposure time application_number US 2160801 A description hereinafter the exposure control method and exposure control apparatus in a lithography system will be explained with reference to the accompanying drawings 0032 fig1 is a block diagram illustrating the lithography system according to the preferred embodiment of the present invention the system comprises a resist coating and developing apparatus 200 a wafer transferring mechanism 250 and an exposure control apparatus 100 which in a preferred embodiment is a stepper the resist coating and developing apparatus 200 coats a wafer with a resist and heats the resist and the wafer in a heating chamber in addition the resist coating and developing apparatus 200 develops the resist patterned by exposure to a light source the transferring mechanism 250 serves to transfer wafers w coated with the resist from the resist coating and developing.