Characteristics Improvement and Practical Applications of Sialon Phosphors

Abstract

α-Sialon and β-Sialon phosphors activated by Eu²⁺ are suitable for white LEDs used as LCD backlights and illuminations because of their excellent properties such as long-term reliability and small temperature dependency of photoluminescence emission intensity. α-Sialon phosphor emits yellow/orange fluorescent light and β-Sialon phosphor emits green fluorescent light.

During firing by the gas pressure sintering method, the emission intensity of β-Sialon phosphor was increased with grain growth by Ostwald ripening. We succeeded in improvement of the emission intensity by optimizing synthesis conditions, and the emission intensity can be increased three times more. β-Sialon phosphor is adopted for backlights of LED TV.

The emission wavelength of α-Sialon phosphor can be tuned from yellow to orange by composition tailoring. Amber color LED devices were demonstrated using orange α-Sialon phosphor. It is suitable for winkers of automobiles and adopted for this application.