Light emitting element and light emitting device

A light emitting element comprising:

• a first electrode;
• a hole injection layer over the first electrode;
• a first light emitting layer over the hole injection layer, the first light emitting layer comprising a first host material and a guest material;
• a second light emitting layer formed over the first light emitting layer, the second light emitting layer consisting of containing a second host material and a phosphorescent material, and
• a second electrode formed over the second light emitting layer,
• wherein the first light emitting layer has an emission spectrum with maximum intensity in a wavelength region of at least 400 nm and at most 500 nm,
• wherein the second light emitting layer has an emission spectrum with at least two intensity peaks in a wavelength region of at least 500 nm and at most 700 nm,
• wherein the phosphorescent material is an organic metal complex with platinum as a central metal and including a platinum-carbon bond,
• wherein the phosphorescent material is dispersed to the second host material at a concentration of at least 15 wt%, and
• wherein the light emitting element emits white light.

A light emitting element comprising:

• a first electrode;
• a hole injection layer over the first electrode;
• a first light emitting layer over the hole injection layer, the first light emitting layer comprising a first host material and a guest material;
• a second light emitting layer formed over the first light emitting layer, the second light emitting layer containing a second host material and a phosphorescent material, and
• a second electrode formed over the second light emitting layer,
• wherein the first light emitting layer has an emission spectrum with maximum intensity in a wavelength region of at least 400 nm and at most 500 nm,
• wherein the second light emitting layer has an emission spectrum with at least two intensity peaks in a wavelength region of at least 500 nm and at most 700 nm,
• wherein the phosphorescent material is an organic metal complex with platinum as a central metal and including a platinum-carbon bond,
• wherein the second light emitting layer is capable of simultaneously generating phosphorescent emission from the phosphorescent material and excimer emission from the phosphorescent material,
• wherein the phosphorescent material is dispersed to the second host material at a concentration of at least 15 wt%, and
• wherein the light emitting element emits white light.

A light emitting element comprising:

• an anode;
• a hole injection layer over the anode;
• a first light emitting layer over the hole injection layer, the first light emitting layer comprising a first host material and a guest material;
• a second light emitting layer formed over the first light emitting layer, the second light emitting layer containing a second host material and a phosphorescent material;
• an electron transporting layer over the second light emitting layer;
• an electron injection layer over the electron transporting layer;
• and
• a cathode formed over the electron injection layer,
• wherein the first light emitting layer exhibits blue emission,
• wherein the phosphorescent material is an organic metal complex with platinum as a central metal and including a platinum-carbon bond, wherein the phosphorescent material is dispersed to the second host material at a concentration of at least 15 wt%, and
• wherein the light emitting element emits white light.

A light emitting element comprising:

• a first electrode;
• a hole injection layer over the first electrode;
• a first light emitting layer over the hole injection layer, the first light emitting layer comprising a first host material and a guest material;
• a second light emitting layer containing a second host material and a phosphorescent material over the first light emitting layer;
• an electron transporting layer over the second light emitting layer;
• an electron injection layer over the electron transporting layer, and
• a cathode formed over the electron injection layer,
• wherein the first light emitting layer has an emission spectrum with maximum intensity in a wavelength region of at least 400 nm and at most 500 nm,
• wherein the second light emitting layer has an emission spectrum with at least two intensity peaks in a wavelength region of at least 500 nm and at most 700 nm,
• wherein the phosphorescent material is an organic metal complex with platinum as a central metal and including a platinum-carbon bond, wherein the phosphorescent material is dispersed to the second host material at a concentration of at least 15 wt%, and
• wherein the light emitting element emits white light.

A semiconductor device comprising:

• a first electrode formed over a substrate;
• a hole injection layer over the first electrode;
• a first light emitting layer formed over the hole injection layer, the first light emitting layer exhibiting blue emission and comprising a first host material and a guest material;
• a second light emitting layer formed over the first light emitting layer, the second light emitting layer containing a second host material and a phosphorescent material;
• a second electrode formed over the second light emitting layer;
• and
• a color filter formed over the second electrode,
• wherein the phosphorescent material is an organic metal complex with platinum as a central metal and including a platinum-carbon bond, wherein the phosphorescent material is dispersed to the second host material at a concentration of at least 15 wt%, and
• wherein the second light emitting layer is capable of simultaneously generating phosphorescent emission from the phosphorescent material and excimer emission from the phosphorescent material.

A semiconductor device comprising:

• a first electrode formed over a substrate;
• a hole injection layer over the first electrode;
• a first light emitting layer formed over the hole injection layer, the first light emitting layer comprising a first host material and a guest material;
• a second light emitting layer formed over the first light emitting layer, the second light emitting layer containing a second host material and a phosphorescent material,
• a second electrode formed over the second light emitting layer;
• and
• a color filter formed over the second electrode,
• wherein the first light emitting layer has an emission spectrum with maximum intensity in a wavelength region of at least 400 nm and at most 500 nm,
• wherein the second light emitting layer has an emission spectrum with at least two intensity peaks in a wavelength region of at least 500 nm and at most 700 nm,
• wherein the phosphorescent material is an organic metal complex with platinum as a central metal and including a platinum-carbon bond, wherein the phosphorescent material is dispersed to the second host material at a concentration of at least 15 wt%, and
• wherein the second light emitting layer is capable of simultaneously generating phosphorescent emission from the phosphorescent material and excimer emission from the phosphorescent material.