To reduce the number of layers of an EL layer so that it can be manufactured at a reduced cost. An electrode (a) (102) and an EL layer (103) are formed on an insulator (101), and the EL layer (103) is subjected to plasma processing. A carrier injection region (104) is formed as a result in a superficial portion of the EL layer (103). An electrode (b) (105) is formed thereon to complete an EL element. The EL layer (103) is high in carrier injection efficiency despite being substantially a single layer.