Light-emitting device and electronic apparatus including the same

A light-emitting device comprising:

• a first electrode;
• a second electrode facing the first electrode;
• and
• an interlayer comprising an emission layer between the first electrode and the second electrode and a hole transport region between the first electrode and the emission layer,
• wherein the emission layer comprises a dopant,
• the hole transport region comprises a first hole transport layer, a second hole transport layer between the first hole transport layer and the emission layer, and a third hole transport layer between the second hole transport layer and the emission layer,
• the first hole transport layer comprises a first compound,
• the second hole transport layer comprises a second compound,
• the third hole transport layer comprises a third compound,
• the first to third compounds are each independently an amine-based compound, and are different from each other, and
• Equation 1 is satisfied:
• T1(HTM3)≥T1(D)+0.3 eV, and Equation 1
• wherein, in Equation 1,
• T1(HTM3) is a triplet energy level in electron volt (eV) of the third compound,
• T1(D) is a triplet energy level in electron volt (eV) of the dopant, and
• T1(HTM3) and T1(D) are values evaluated utilizing a density functional theory (DFT) method of a Gaussian program, which is structure-optimized at a B3LYP/6-31G(d,p) level,
• wherein
• the first electrode is patterned according to a first subpixel, a second subpixel, and a third subpixel,
• the emission layer comprises a first emission layer that is formed in the first subpixel and is to emit a first-color light, a second emission layer that is formed in the second subpixel and is to emit a second-color light, and a third emission layer that is formed in the third subpixel and is to emit a third-color light,
• the first hole transport layer and the second hole transport layer are common layers formed over all of the first subpixel, the second subpixel, and the third subpixel,
• the third hole transport layer comprises a hole transport layer 3-1 formed in the first subpixel, a hole transport layer 3-2 formed in the second subpixel, and a hole transport layer 3-3 formed in the third subpixel,
• the first emission layer comprises a first dopant,
• the second emission layer comprises a second dopant,
• the third emission layer comprises a third dopant,
• the hole transport layer 3-1 comprises a first third compound,
• the hole transport layer 3-2 comprises a second third compound,
• the hole transport layer 3-3 comprises a third third compound,
• the first third compound comprised in the hole transport layer 3-1, the second third compound comprised in the hole transport layer 3-2, and the third compound comprised in the hole transport layer 3-3 are identical to or different from each other, and
• Equation 2 is satisfied:
• T1(HTM3-1)>T1(D1);
• T1(HTM3-2)>T1(D2);
• and
• T1(HTM3-3)>T1(D3), Equation 2
• wherein, in Equation 2,
• T1(HTM3-1) is a triplet energy level in electron volt (eV) of the first third compound comprised in the hole transport layer 3-1,
• T1(HTM3-2) is a triplet energy level in electron volt (eV) of the second third compound comprised in the hole transport layer 3-2,
• T1(HTM3-3) is a triplet energy level in electron volt (eV) of the third third compound comprised in the hole transport layer 3-3,
• T1(D1) is a triplet energy level in electron volt (eV) of the first dopant,
• T1(D2) is a triplet energy level in electron volt (eV) of the second dopant,
• T1(D3) is a triplet energy level in electron volt (eV) of the third dopant, and
• T1(HTM3-1) to T1(HTM3-3) and T1(D1) to T1(D3) are values evaluated utilizing the DFT method of the Gaussian program, which is structure-optimized at the B3LYP/6-31G(d,p) level.