中子辐照含氢硅中的一种新EPR谱

氢气氛下生长的区熔硅(磷～10¹⁴/cm³)经镉比为10,总通量为(2.9—6.0)×10¹⁷n/cm²的中子辐照后,在77K,X波段观测到一种S=1/2的新EPR谱(标号为PK2)。g_eff值随(011)平面内磁场的角度关系呈三斜对称性。对应于缺陷在硅中一特定取向下的g张量主值及主轴相对于立方晶轴的方向余弦如下:g(±0.0004) n[100] n[010] n[001] g_{1关键词：}

A NEW EPR SPECTRUM IN NEUTRON IRRADIATED SILICON CONTAINING HYDROGEN

The n-type FZ silicon (P～10¹⁴/cm³) grown in hydrogen is irradiated with neutrons of the total flux of (2.9-6.0)×10¹⁷n/cm² and with Cd ratio about 10 at room temperature. An S=1/2 EPR spectrum, labeled Si-PK2, is found in X band and at 77K. The angular dependence of the g_eff values with H in the (011) plane has a tricliuic symmetry. For one of the equivalent defect orientations the principle values of the g tensor and the direction cosines of the principle axes with respect to the cubic axes are as follows: g(±0.0004) n[100] n[010] n[001] g₁=2.0028 -0.5154 0.8473 -0.1283 g₂=2.0063 -0.7386 -0.5151 -0.4347 g₃=1.9971 -0.4344 -0.1293 0.8914 The simulated EPR spectra computed from the g tensor are consistent with the experimental results.The PK2 EPR spectrumappears in the unannealed neutron irradiated samples and remains until 300℃ annealing. It is probebly due to a kind of defects which is depen-tent of the hydrogen.