| 摘要 |
PROBLEM TO BE SOLVED: To set an ionization potential(Ip) of the surface of an anode in contact with a hole injection transport layer to a required value at the stage of film formation of the anode in manufacturing an organic electroluminescent element. SOLUTION: An anode 3 made of an ITO film is formed by sputtering on the surface of a glass substrate 2 in the mixed gas atmosphere of Ar and O2. A first layer 6 in first 95 nm is formed under the condition that Ar:O2=25 sccm:1 sccm and a second layer (an interface 6) in the residual 5 nm layer is formed under the condition that Ar:O2=25 sccm:10 sccm. The interface 5 of the anode 3 has the Ip of 6.0 eV and a resistance of 300Ω. The first layer 6 has the Ip of 4.5 eV and a resistance of 100Ω. The entire anode 3 has a sheet resistance of 100Ω/(square) or less and the Ip of 5.5 eV. An insulating layer 7, a hole injection transfer layer 4, a light emitting layer 8 and a cathode 9 are laminated in this order on the anode 3. The anode 3 made of ITO has a small resistance as a whole and the Ip approximate to that of the hole injection transfer layer 4 at the interface in contact therewith. Consequently, it is possible to achieve excellent hole injection characteristic and a luminance much higher than that of the prior art.
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