面向对注氢硅片中微结构的影响

把不同面向的注氢硅片制成横截面样品,在高分辨率透射电子显微镜下进行观察,发现衬底面向对其中的微结构有明显的影响.首先表现为衬底中主要出现平行于正表面的氢致片状缺陷,即(10 0 )衬底中,主要出现平行于正表面的{ 10 0 }片状缺陷,而(111)衬底中出现的主要是平行于正表面的{ 111}片状缺陷.其原因是注入引起垂直正表面的张应变.另外,面向的影响还表现为,(10 0 )衬底中出现的{ 113}缺陷在(111)衬底中不出现.在(111)衬底中出现的晶格紊乱团和空洞在(10 0 )衬底中不出现.从而推测,{ 111}片状缺陷的形成不发射自间隙原子,而(10 0 )片状缺陷的形成将发射自

Effect of Substrate Orientation on Microstructure of Hydrogen-Implanted Silicon Wafers

As-implanted (100) and (111) wafers are prepared into cross-sectional samples and observed with high resolution transmission electronic microscopy (HRTEM).In (111) or (100)- oriented silicon,a great population of platelets are observed.Platelets laying on (100) planes or (111)ones do not disrupt Si lattice but led to distortion of lattice.It is also exhibited that substrate orientation works remarkably on the microstructure of wafers.In (100) substrate,there appear preferentially {100} platelets parallel to top surface.In (111) substrate,{111} platelets parallel to top surface are in the majority.The preferential production of platelets is attributed to the tensile strain vertical to the top surface in silicon wafer.Furthermore,the effect of orientation has another meaning.{113} planar defects emerge in (100) silicon substrates but not in (111)silicon.Disorder clumps and voids appear in (111)silicon but not in (100) silicon.