摘要
结合激光退火与常规热退火方法对超薄非晶硅层作用,在绝缘衬底上获得了高密度的、均匀的单层纳米硅结构.所得样品通过原子力显微镜、透射电子显微镜和Raman散射谱进行表征,证实了晶化过程的发生和纳米硅晶粒的形成.在得到的5nm厚晶化样品中观察到在660nm左右范围内光致发光峰,初步的分析表明其发光与纳米硅晶粒的形成有关.
Silicon nanostructures with high density （up to 10^11 cm^-2） and with a lateral size of 10-30nm and a vertical size limited by the film thickness are fabricated on insulating SiNx layers by combining laser irradiation on an ultrathin （4-30nm） amorphous Si film and subsequent thermal annealing. Atomic force microscopy,transmission electron microscopy,and Raman scattering spectroscopy are employed to characterize the surface morphology,crystallization process＇ and crystallite. The influence of the laser irradiation and the thickness of the initial amorphous Si layer on the formation of the Si nanostructures is studied. A strong photoluminescence with a peak located at about 660nm, which we tentatively attribute to the crystalline Si grains, can be detected from the 5nm thick crystallized sample.
基金
国家自然科学基金资助项目(批准号:10374049
60425414
50472066)~~
关键词
纳米硅
激光晶化
光致发光
nanocrytalline Si
laser crystallization
photoluminescence
