Open AccessEL emission enhancement in powder electroluminescent device via insertion of receptive layer
Author(s) -
Takeda N.,
Tsuneyasu S.,
Satoh T.
Publication year - 2020
Publication title -
electronics letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.375
H-Index - 146
ISSN - 1350-911X
DOI - 10.1049/el.2019.3085
Subject(s) - materials science , electroluminescence , optoelectronics , luminance , capacitance , substrate (aquarium) , dielectric , insertion loss , electrode , layer (electronics) , voltage , dissipation factor , optics , electrical engineering , composite material , chemistry , physics , oceanography , engineering , geology
A method to enhance the electroluminescence (EL) of powder electroluminescent devices via the insertion of a receptive layer between the letter substrate and the transparent electrode is proposed. This approach affords uniformity of distance between the substrate and electrode, which ensures a more uniform electric field on application of a voltage to the device. Both the current and luminance are observed to increase, and the device capacitance and capacitive reactance improve on introduction of the receptive layer, which enhances the EL properties. The emission‐enhancement mechanism is examined via measurements of the frequency dependence of the current, luminance, and loss tangent tan δ . Regardless of the receptive layer, the current decreases in the frequency regime over which tan δ increases, which indicates that the EL properties are affected by electrical energy losses due to dielectric loss. The frequency‐dependence behaviours of tan δ and temperature are found to be different because of heat production due to both dielectric loss and radiationless deactivation, which means that dielectric loss must be reduced to improve device efficiency. Their approach can form an integral aspect of the evaluation of powder electroluminescent devices.