A device, comprising: a first electrode and a second electrode; an active layer between the first electrode and the second electrode; and a plurality of auxiliary layers between the first electrode and the active layer, wherein the plurality of auxiliary layers includes a first auxiliary layer and a second auxiliary layer, the first auxiliary layer proximate to the active layer in relation to the second auxiliary layer, the second auxiliary layer proximate to the first electrode in relation to the first auxiliary layer, wherein the first auxiliary layer is in contact with the active layer, wherein the second auxiliary layer is in contact with the first electrode, wherein a HOMO energy level of the active layer, a HOMO energy level of the first auxiliary layer, a HOMO energy level of the second auxiliary layer, and a work function of the first electrode become sequentially shallower from a vacuum level, such that a magnitude of the HOMO energy level of the first auxiliary layer is between a magnitude of the HOMO energy level of the active layer and a magnitude of the HOMO energy level of the second auxiliary layer, and the magnitude of the HOMO energy level of the second auxiliary layer is between the magnitude of the HOMO energy level of the first auxiliary layer and a magnitude of the work function of the first electrode, characterized in that the active layer, the first auxiliary layer, the second auxiliary layer, and the first electrode satisfy Relationship Equations 1E, 2E and 3E: 0 < ΔΦ 1 − ΔΦ 2 ≤ 0.05 eV 0 < ΔΦ 1 − ΔΦ 3 ≤ 0.05 eV 0 < ΔΦ 3 − ΔΦ 2 ≤ 0.05 eV wherein, in Relationship Equations 1E, 2E and 3E, ΔΦ 1 is a difference between the HOMO energy level of the active layer and the HOMO energy level of the first auxiliary layer, ΔΦ 2 is a difference between the HOMO energy level of the second auxiliary layer and the work function of the first electrode, and ΔΦ 3 is a difference between the HOMO energy level of the first auxiliary layer and the HOMO energy level of the second auxiliary layer, wherein the work function and HOMO energy levels are obtained by measuring a photoelectric work function of thin films using photoelectron spectroscopy as defined in the description. a first electrode and a second electrode; an active layer between the first electrode and the second electrode; and a plurality of auxiliary layers between the first electrode and the active layer, wherein the plurality of auxiliary layers includes a first auxiliary layer and a second auxiliary layer, the first auxiliary layer proximate to the active layer in relation to the second auxiliary layer, the second auxiliary layer proximate to the first electrode in relation to the first auxiliary layer, wherein the first auxiliary layer is in contact with the active layer, wherein the second auxiliary layer is in contact with the first electrode, wherein a HOMO energy level of the active layer, a HOMO energy level of the first auxiliary layer, a HOMO energy level of the second auxiliary layer, and a work function of the first electrode become sequentially shallower from a vacuum level, such that a magnitude of the HOMO energy level of the first auxiliary layer is between a magnitude of the HOMO energy level of the active layer and a magnitude of the HOMO energy level of the second auxiliary layer, and the magnitude of the HOMO energy level of the second auxiliary layer is between the magnitude of the HOMO energy level of the first auxiliary layer and a magnitude of the work function of the first electrode, characterized in that the active layer, the first auxiliary layer, the second auxiliary layer, and the first electrode satisfy Relationship Equations 1E, 2E and 3E: 0 < ΔΦ 1 − ΔΦ 2 ≤ 0.05 eV 0 < ΔΦ 1 − ΔΦ 3 ≤ 0.05 eV 0 < ΔΦ 3 − ΔΦ 2 ≤ 0.05 eV characterized in that the active layer, the first auxiliary layer, the second auxiliary layer, and the first electrode satisfy Relationship Equations 1E, 2E and 3E: 0 < ΔΦ 1 − ΔΦ 2 ≤ 0.05 eV 0 < ΔΦ 1 − ΔΦ 3 ≤ 0.05 eV 0 < ΔΦ 3 − ΔΦ 2 ≤ 0.05 eV wherein, in Relationship Equations 1E, 2E and 3E, ΔΦ 1 is a difference between the HOMO energy level of the active layer and the HOMO energy level of the first auxiliary layer, ΔΦ 2 is a difference between the HOMO energy level of the second auxiliary layer and the work function of the first electrode, and ΔΦ 3 is a difference between the HOMO energy level of the first auxiliary layer and the HOMO energy level of the second auxiliary layer, wherein the work function and HOMO energy levels are obtained by measuring a photoelectric work function of thin films using photoelectron spectroscopy as defined in the description. ΔΦ 1 is a difference between the HOMO energy level of the active layer and the HOMO energy level of the first auxiliary layer, ΔΦ 2 is a difference between the HOMO energy level of the second auxiliary layer and the work function of the first electrode, and ΔΦ 3 is a difference between the HOMO energy level of the first auxiliary layer and the HOMO energy level of the second auxiliary layer, wherein the work function and HOMO energy levels are obtained by measuring a photoelectric work function of thin films using photoelectron spectroscopy as defined in the description.