【摘要】 采用提拉法生长Ce∶YAG单晶,通过X射线衍射和激发发射光谱对其晶相结构和光谱特性进行了表征,研究了Ce∶YAG单晶封装白光LED的最佳掺杂浓度.在455 nm蓝光激发下,Ce∶YAG单晶的发射光谱可由中心波长526 nm(5d12E gГ8g→4f12F7/2Г8u)的宽发射带(500~650 nm)组成;激发光谱由343 nm(4f12F5/2Г7u→5d1 2E gГ7g)和466 nm(4f12F5/2Г7u→5d1 2E gГ8g)2个激发峰组成;Stokes位移为2448 cm-1,Huang-Rhys因子为6.12.研究结果表明,Ce∶YAG单晶中Ce离子掺杂浓度与封装的白光LED之间有对应关系,在650 nm红粉调节下Ce离子最佳掺杂浓度范围为0.034~0.066.更多还原

【Abstract】 Ce∶ YAG single crystal for white light emitting diode( WLED) was grown by Czochralski method. The structure and optical properties of samples were characterized by X-ray diffraction( XRD) and photoluminescence spectra. Ce ∶ YAG single crystal shows a 500—650 nm broad emission band around 526 nm( 5d1 2E g Г 8g →4f1 2F 7 /2 Г 8u) under blue light of 455 nm. The excitation spectrum of Ce∶ YAG single crystal is made up of 343 nm( 4f1 2F 5 /2 Г7u →5d1 2E g Г7g) and 466 nm( 4f1 2F 5 /2 Г7u →5d1 2E g Г8g) excitation peaks. The Stokes shift is 2448 cm- 1. The Huang-Rhys parameter is 6. 12. The Ce concentration of Ce∶ YAG single crystal is related with colour coordinate of WLEDs made by Ce∶ YAG single crystal with the red phosphor( 650 nm),a best concentration range of Ce in Ce∶ YAG single crystal is 0. 034—0. 066.更多还原