A method of forming a plurality of multi-layer organic films in a single process includes preparing a first evaporating source that evaporates a first evaporating source material onto a first deposition region and a second evaporating source that evaporates a second evaporating source material onto a second deposition region, wherein the first evaporating source material and the second evaporating source material are different from each other, adjusting the first evaporating source and the second evaporating source in order to obtain a first overlapping region in which the first deposition region and the second deposition region overlap each other, driving the first evaporating source and the second evaporating source to deposit the first evaporating source material and the second evaporating source material onto a portion of an object to be processed, and moving the first evaporating source and the second evaporating source from a first end of the object to a second end of the object to form a multilayer film comprising a first layer that is a deposition of only the first evaporating source material, a second layer that is a deposition of a mixture of the first evaporating source material and the second evaporating source material and a third layer that is a deposition of only the second source material.