Provided is a means for improving the capability of injecting electrons
from a cathode in a luminous element and solving problems about the
production process thereof. In the present invention, a material having a
smaller work function than a cathode material is used to form an
inorganic conductive layer between the cathode and an organic compound
layer. In this way, the capability of injecting electrons from the
cathode can be improved. Furthermore, the film thereof can be thicker
than that of a conventional cathode buffer layer formed by using an
insulating material. Therefore, the film thickness can easily be
controlled, and a decrease in production costs and an improvement in
yield can be achieved.