高剂量铂和钇离子注入Al_2O_3单晶的表面改性

Surface modification of sapphire implanted with high dose yttrium and platinum ions

研究了＜0001＞和＜1210＞晶向α－Al2O3单晶在高剂量的Y、Pt离子注入后产生的损伤，注入层的性能变化和退火行为。实验结果表明，在室温，171keV、1×1017／cm2Y离子注入的＜1210＞α－Al2O3单晶的表面层约有139nm厚被无定形化。而158keV、9×1017／cm2Pt离子注入的＜0001＞α-Al2O3单晶的表面层不产生无定形，且实际离子注入进衬底的剂量只有2．65×1016／cm2，绝大部分在注入过程中被溅射掉。注入后其表面层的硬度提高了大约50％。表面层的电阻率降低了12个数量级。在空气中退火后形成了随机取向的纳米量级大小的Pt微晶，表面层的硬度也有所降低，但仍稍高于未注入的单晶硬度。

The c-axis and a-axis single crystals of a -Al2O3 implanted with 1 ×1017/cm2 of 171keV Y ions, and 9×1017/cm2 of 158keV Pt ions, respectively, have been investigated. The implantation was carried out at room temperature by using a MEVVA machine. Annealing was performed isothermally in air ambient at temperature in the range from 500℃ to 1050℃. The rutherford backscattering spectrometry and channeling of 2.4MeV He+ was used to study the depth distribution of lattice damage and implants. The microhardness and resistivity of the implanted layer were also measured. Results on structural changes were interpreted on the basis of the physical property measurements. The precipitates of implanted Pt were examined by XRD.