Light emitting element and display device including the same

A light emitting element comprising:

• a first electrode;
• a hole transport region disposed on the first electrode;
• an emission layer disposed on the hole transport region;
• an electron transport region disposed on the emission layer;
• and
• a second electrode disposed on the electron transport region, wherein
• the hole transport region includes:
• a first hole transport layer disposed adjacent to the first electrode and including a first amine compound having a first refractive index;
• a second hole transport layer disposed between the first hole transport layer and the emission layer and including a second amine compound having a second refractive index;
• and
• a third hole transport layer disposed between the second hole transport layer and the emission layer and including a third amine compound having a third refractive index, the second amine compound is represented by Formula 3, and
• the first amine compound and the third amine compound are each independently a compound represented by Formula 4:
• wherein in Formula 3,
• z is an integer from 0 to 7,
• Y is C(Rf)(Rg), N(Rh), O, or S,
• L11 is a direct linkage, a substituted or unsubstituted arylene group having 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heteroarylene group having 2 to 30 ring-forming carbon atoms, and
• Rf to Rh and R11 to R14 are each independently a hydrogen atom, a deuterium atom, a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 10 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring-forming carbon atoms, or are bonded to an adjacent group to form a ring,
• wherein in Formula 4,
• R1 is a substituted or unsubstituted adamantyl group, a substituted or unsubstituted cyclohexyl group, or a substituted or unsubstituted bicycloheptyl group,
• Ar1 and Ar2 are each independently a substituted or unsubstituted arylene group having 6 to 30 ring-forming carbon atoms,
• L is a direct linkage, a substituted or unsubstituted arylene group having 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heteroarylene group having 2 to 30 ring-forming carbon atoms,
• X is C(Ra)(Rb), N, N(Rc), O, or S,
• Ra to Rc are each independently a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 10 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring-forming carbon atoms, or are bonded to an adjacent group to form a ring,
• d and e are each independently an integer from 0 to 4, and
• Rd and Re are each independently a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 10 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring-forming carbon atoms, or are bonded to an adjacent group to form a ring.

A display device comprising:

• a plurality of light emitting elements, wherein
• the plurality of light emitting elements each include:
• a first electrode;
• a hole transport region disposed on the first electrode;
• an emission layer disposed on the hole transport region;
• an electron transport region disposed on the emission layer;
• and
• a second electrode disposed on the electron transport region,
• the hole transport region includes:
• a first hole transport layer disposed adjacent to the first electrode and including a first amine compound having a first refractive index;
• a second hole transport layer disposed between the first hole transport layer and the emission layer, and including a second amine compound having a second refractive index greater than the first refractive index;
• and
• a third hole transport layer disposed between the second hole transport layer and the emission layer, and including a third amine compound having a third refractive index less than the second refractive index, and
• the first amine compound and the third amine compound are each independently a compound represented by Formula 1:
• wherein in Formula 1,
• R1 is a substituted or unsubstituted adamantyl group, a substituted or unsubstituted cyclohexyl group, or a substituted or unsubstituted bicycloheptyl group,
• Ar1 and Ar2 are each independently a substituted or unsubstituted arylene group having 6 to 30 ring-forming carbon atoms,
• L is a direct linkage, a substituted or unsubstituted arylene group having 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heteroarylene group having 2 to 30 ring-forming carbon atoms, and
• FR is a group represented by Formula 2:
• wherein in Formula 2,
• X is C(Ra)(Rb), N, N(Rc), O, or S,
• Ra to Rc are each independently a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 10 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring-forming carbon atoms, or are bonded to an adjacent group to form a ring,
• d and e are each independently an integer from 0 to 4, and
• Rd and Re are each independently a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 10 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring-forming carbon atoms, or are bonded to an adjacent group to form a ring.