Effect of a P-doped hole transport and charge generation layer on single and two-tandem blue top-emitting organic light-emitting diodes

Figures & data

Figure 1. (a) Single blue TEOLED. (b) Tandem blue TEOLED structure. (c) EL spectrum in the single and tandem blue TEOLEDs.

Figure 2. (a) Transmittance and (b) refractive index (n), extinction coefficient (k), and photoluminescence (PL) intensity of the EML.

Figure 3. (a) Current density versus voltage (J-V), (b) luminance versus voltage (L-V), and (c) current efficiency versus luminance (η_c-L) characteristics of the blue TEOLEDs in this study.

Table 1. Integrating sphere analysis of the single and two-tandem blue TEOLEDs

	Single TEOLEDs ^a		Tandem TEOLEDs ^b
Doping ratio	EQE (%)	Voltage (V)	EQE (%)	Voltage (V)
5%	6.2	4.68	11.55	7.33
10%	6.14	4.35	12.32	6.6
15%	5.91	4.4	12.4	6.57
20%	5.88	4.44	12.29	6.53

Figure 4. Simulation of the normalized EQE versus the optimized thickness of (a) p-HTL and (b) p-CGL depending on the doping ratio.