激光干涉结晶技术制备二维有序分布纳米硅阵列

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

利用结合移相光栅掩模(PSGM)的激光结晶技术在超薄a-SiNx/a-Si:H/a-SiNx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-SiNx为50nm,衬底材料为SiO2/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>.

The method of laser-induced crystallization combining with the phase-shifting grating mask (PSGM) was carried out to fabricate nanocrystal silicon (ne-Si) with the two-dimensional (2D) patterned distribution within a-SiNx/a-Si: H/a-SiNx sandwiched structure grown on the SiO2/Si or fused quartz substrate by plasma-enhanced chemical vapor deposition technique. The thicknesses of a-Si: H and a-SiNx layer are 10 and 50 nm, respectively. The results of atomic force microscopy, cross-section transmission electron microscopy and high resolution transmission electron microscopy show that the controllable crystallized regions within the initial a-Si: H layer are selectively formed with a diameter of about 250 nm and are patterned with the same 2D periodicity of 2.0 mu m 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 have < 111 > preferred orientation.