The concentration of oxygen, which causes problems such as decreases in brightness
and dark spots through degradation of electrode materials, is lowered in an organic
light emitting element having a layer made from an organic compound between a cathode
and an anode, and in a light emitting device structured using the organic light
emitting element. The average concentration of impurities contained in a layer
made from an organic compound used in order to form an organic light emitting element
having layers such as a hole injecting layer, a hole transporting layer, a light
emitting layer, an electron transporting layer, and an electron injecting layer,
is reduced to 51019/cm2 or less, preferably equal to
or less than 11019/cm2, by removing the impurities
with the present invention. Formation apparatuses are structured as stated in the
specification in order to reduce the impurities in the organic compounds forming
the organic light emitting elements.
