Preparation of a YAG:Ce phosphor glass by screen-printing technology and its application in LED packaging

Abstract

A simple and practical method for preparing phosphor glass is proposed. Phosphor distribution and element analysis are investigated by optical microscope and field emission scanning electron microscope (FE-SEM). The phosphor particles dispersed in the matrix are vividly observed, and their distributions are uniform. Spectrum distribution and color coordinates dependent on the thickness of the screen-printed phosphor layer coupled with a blue light emitting diode (LED) chip are studied. The luminous efficacy of the 75 μm printed phosphor-layer phosphor glass packaged white LED is 81.24 lm/W at 350 mA. This study opens up many possibilities for applications using the phosphor glass on a selected chip in which emission is well absorbed by all phosphors. The screen-printing technique also offers possibilities for the design and engineering of complex phosphor layers on glass substrates. Phosphor screen-printing technology allows the realization of high stability and thermal conductivity for the phosphor layer. This phosphor glass method provides many possibilities for LED packing, including thin-film flip chip and remote phosphor technology.

Solvothermal nanoYAG synthesis: Mechanism and particle growth kinetics

“…For example, with a suitable dopant on the yttrium site in the crystal structure, excellent optical properties can be achieved for laser and white LED applications [2,3]. The ceramic is also being researched for other uses such as a radar dome [4] and as a highly creep-resistant material at high temperatures [5].…”

Glass Ceramic Phosphors: Towards Long‐Lifetime High‐Power White Light‐Emitting‐Diode Applications–A Review

“…Screen printing has been extensively used for microelectronics and the packaging of passive components, but only in more recent years did it apply to the phosphor‐glass color converter for w‐LEDs, firstly reported by Yang et al . Figure schematically illustrates the preparation route of screen printing, i.e., an ink paste, made of phosphor, glass, organic solvent, and adhesives, is coated on the surface of glass plate by using a squeegee, followed by drying and sintering the composite.…”

“…Schematic illustration of GC preparation via screen‐printing route. Reproduced with permission . Copyright 2013, American Optical Society.…”

“…Depositing glass‐phosphor composite on glass substrate in the form of film via screen‐printing or tape‐casting also attracts the researchers’ interests. For example, Liu's group reported a well‐defined and homogeneous film containing the SiO 2 ‐B 2 O 3 ‐PbO glass powder and the YAG:Ce 3+ phosphor, which is printed onto a glass substrate ( Figure a) . YAG:Ce 3+ in the size of ≈13 μm are found well distributed among the glass matrix without agglomeration (Figure b).…”

Performance Enhancement of White LEDs Through Phosphor/Silicone Composite Particles

“…There is a continuous effort to further improve their optical performance in order to make them the dominant light source for illumination [3][4][5]. Apart from optical performances, the high price of LED products still sets the main obstacle for further development.…”