Thermal Properties of Mn4+-Doped Complex Fluoride Phosphors

Wednesday, October 14, 2015: 08:40
Phoenix West (Hyatt Regency)
A. A. Setlur, J. Murphy, F. Garcia-Santamaria (GE Global Research), and S. Sista (GE Global Research)
Red phosphors based upon Mn4+-doped complex fluorides are currently being implemented in a variety of LED display and lighting applications.  These phosphors can enable high CRI (for lighting) or high color gamut (for LCD backlit displays) without significant efficiency losses.  However, the properties of these phosphors can significantly differ based upon the specific phosphor host.  One example is in the temperature quenching of luminescence where T0.5, the temperature where emission intensity reaches 50% of the room temperature value.  Different Mn4+-doped complex fluoride phosphors can have T0.5 values that vary by more than 100oC.  In many applications, these differences in thermal quenching can prevent the use of these materials In this presentation, we discuss the various properties of numerous Mn4+-doped complex fluoride phosphors as a function of temperature.  Correlations between composition, vibrational properties, and luminescence properties will be discussed and analyzed.  Finally, the presence (or absence) of thermal quenching as a function of Mn4+ concentration will also be presented.