激光干涉结晶技术制备二维有序分布纳米硅阵列

利用结合移相光栅掩模 (PSGM) 的激光结晶技术在超薄a-SiN_x/a-Si:H/ a-SiN _x三明治结构样品中制备出二维有序分布的纳米硅阵列.原始样品是用等离子体 增强化学气相淀积法生长.a-Si:H层厚为10nm，a-SiN_x 为50nm，衬底材料为SiO ₂/Si或 熔凝石英.原子力显微镜、剖面透射电子显微镜、高分辨透射电子显微镜对样品表面形貌和 微结构的观测结果表明，采用该方法可以在原始淀积的a-Si:H层中得到位置可控的晶化区域 ：每个晶化区域直径约250nm，具有同PSGM一致的2μm周期；晶化区域内形成的纳米硅 颗粒尺寸接近原始淀积的a-Si:H层厚，且晶粒的择优取向为<111>. 关键词： 纳米硅 激光结晶 定域晶化 移相光栅

Two-dimensional patterned nc-Si arrays prepared by the method of laser interference crystallization

The method of laser_induced crystallization combining with the phase-shifting grating mask (PSGM) was carried out to fabricate nanocrystal silicon (nc-Si) with the two-dimensional (2D) patterned distribution within a-SiN_x/a- Si:H/ a-SiN_x sandwiched structure grown on the SiO₂/Si or fuse d quartz subst rate by plasma-enhanced chemical vapor deposition technique. The thicknesses of a-Si:H and a-SiN_x layer are 10 and 50nm, respectively. The results of at omic force microscopy, cross-section transmission electron microscopy and high r esolution transmission electron microscopy show that the controllable crystalliz ed regions within the initial a-Si:H layer are selectively formed with a diamete r of about 250 nm and are patterned with the same 2D periodicity of 20 μm as that of the PSGM. Si nano-crystallites，the size of which is almost the same as the thickness of the a-Si:H layer, are formed in the crystallized regions, and h ave <111> preferred orientation.