N-B-Al共掺荧光4H-SiC施主受主对发光性能研究  

Luminescence of Donor-acceptor-pair in Fluorescent 4H-SiC Doped with Nitrogen, Boron and Aluminum

作　　者：卓世异[1] 刘熙[1] 高攀[1] 严成锋[1] 施尔畏[1] 

机构地区：[1]中国科学院上海硅酸盐研究所,上海200050

出　　处：《无机材料学报》2017年第1期51-55,共5页Journal of Inorganic Materials

摘　　要：施主受主共掺杂的荧光4H-SiC可以通过复合发出可见光,影响其发光性能的一个重要因素是施主–受主掺杂的浓度。本研究通过PVT生长方法制备了3英寸N-B-Al共掺的4H-SiC晶体,采用Raman光谱、SIMS对晶体的结晶类型和掺杂浓度进行了表征;采用PL发射谱和激发谱、荧光衰减曲线表征和内量子效率对晶体的发光波长、强度、施主–受主对复合发光性能进行了研究。结果发现,低浓度Al掺杂样品在室温下发出黄绿色荧光。低浓度Al掺杂在晶体中提供较少的受主;高浓度B、N掺杂形成施主,从而贡献充足的电子–空穴对。这些电子–空穴的复合提高了施主–受主对复合的内量子效率,进而增强光致发光强度,增加平均发光寿命。Fluorescent 4H-SiC, co-doped with donor and acceptor impurities, can work as phosphor for visible light emission by recombination. Donor concentration and acceptor impurities are two important factors which influence luminescent properties of fluorescent 4H-SiC. In this study, 3 inch N-B-A1 co-doped 4H-SiC crystals were prepared by physical vapor transport method. Crystalline type and N-B-Al concentration of the doped 4H-SiC were measured by Raman spectrum and secondary ion mass spectra. Influences of doping concentrations on the photoluminescence were studied by photoluminescence excitation and emission spectra, luminescence decay curves, and internal and external quantum efficiencies. It is found that p-type fluorescent 4H-SiC with low Al doping concentration shows intensive yellow-green fluorescence at room temperature. Heavily doped N and B and lightly doped Al in 4H-SiC produce enough electron hole pairs for the recombination. This sufficient recombination enhances internal quantum efficiency of fluorescent 4H-SiC. Furthermore, the recombination is also helpful to increase their photoluminescence intensity and average fluorescence lifetime.

关 键 词：碳化硅 光致发光 内量子效率 

分 类 号：TB23[一般工业技术—工程设计测绘]