Substrate processing apparatus capable of detaching a top surface member to easily clean the area around a packaged heater

The present invention relates to a substrate processing apparatus. A top surface unit 83 is detachably constructed relative to a housing. A heater unit 115 is installed to the top surface unit 83 by a supporting and receiving member 105 and a movable hook part 107, and can be detached from the top surface unit 83. Therefore, since the heater unit 115 including the packaged heater and wiring can be easily detached from the top surface unit 83, the top surface unit 83 can be cleaned with a chemical solution or the like. As a result, at the time of maintenance, a top surface member 91 provided with an exhaust port 49 and an internal exhaust pipe 113 where the sublimate is most easily deposited can be detached and then soaked in a chemical solution or the like for wash-up, thereby easily cleaning the area around the packaged heater.