To provide a slot type fluid applicator in which the inner surface of a slot type application head is cleaned uniformly, a photoresist is supplied corresponding to the acceleration/deceleration speed of a table, an accumulation does not occur, the drying nonuniformity of an air flow does not occur, namely, which prevents the occurrence of stripe nonuniformity, haze nonuniformity, and beads in a coating film.

The inner surface of the slot type application head is cleaned by being irradiated with excimer light 172 nm in wavelength. The slot type fluidapplicator has a lot type application head, a mohnopump, and a table. A mohnopump liquid storage tank which is cut off from outside air by an outside air cutting-off box is formed in the mohnopump. a downflow breeze is supplied to the surface of a substrate.