Eu^(3+)离子注入β-Ga_(2)O_(3)单晶的应力变化和发光性质研究

Stress Variation Trend and Luminescent Properties of Eu^(3+) Doped β-Ga_(2)O_(3) Single Crystals by Ion Implantation

采用离子注入法制备了不同剂量的β-Ga_(2)O_(3)∶Eu^(3+)样品,并在空气中进行了退火处理,成功实现了Eu^(3+)的光学激活。通过拉曼和X射线衍射表征了β-Ga_(2)O_(3)晶体随Eu^(3+)注入剂量的应力变化趋势,发现随着Eu^(3+)剂量的增加,晶格应力先增加后减少,并对其内在机理进行了分析。利用阴极荧光光谱对晶体的发光性质进行了表征,主要观察到峰值位于380 nm附近、宽的缺陷发光峰以及峰值位于591 nm、597 nm和613 nm的Eu^(3+)发光峰。通过高斯拟合发现,该380 nm发光峰主要由360 nm、398 nm和442 nm三个子峰构成,分别与自陷激子和施主-受主对有关。此外,Eu^(3+)发光峰位置与强度受到基质局域晶体场的影响。

β-Ga_(2)O_(3)∶Eu^(3+) samples with different fluence were prepared by ion implantation method and then annealed in air where Eu^(3+) optical activation was successfully achieved.The stress variation trend ofβ-Ga_(2)O_(3) single crystals with Eu^(3+) fluence was characterized by Raman spectra and X-ray diffraction.It was found that with the increase of Eu^(3+) fluence,the crystal lattice stress increases first and then decreases,and its internal mechanism was analyzed.The luminescence properties of Eu3+ were characterized by cathodoluminescence spectra.The wide defect luminescence peak near 380 nm and the characteristic luminescence peaks of Eu^(3+) near 591 nm,597 nm and 613 nm were observed.By Gaussian fitting,the 380 nm luminescence peak could be divided into three peaks located at about 360 nm,398 nm and 442 nm,which are related to the self-trapping excitons and donor-acceptor pairs,respectively.In addition,the position and intensity of Eu^(3+) luminescence peaks were affected by the localized crystal field of the host.