用分子束外延在多孔硅衬底上外延单晶硅来实现SOI结构

SOI Structure Formed by Molecular Beam Epitaxial Growth of Single Crystalline Si on Porous-Si Substrates

用 HF溶液对单晶Si片进行阳极化处理,形成多孔 Si.将多孔Si衬底放入超高真空室在小剂量的Si原子束辐照下进行加热处理,在较低温度下(725—750℃)获得了清洁有序的表面.用分子束外延在多孔Si上生长了1-2μm的单晶Si膜,其卢瑟福背散射沟道产额极小X_(min)<3％,表明外延膜的单晶性能良好.SOI结构已通过随后的侧向氧化多孔Si层获得.

Porous silicon layers were formed by anodization of Si wafers in hydrofluoric (HF) solu-tion.After thermal annealing the as-grown porous silicon under small flux Si beam irradia-tion in ultra-high vacuum system, the authors can obtain clean and ordered porous-Si surfacesat lower temperatures (725-750℃).The single crystal Si layers with thicknesses of 1-2μmhave been grown on such surfaces by molecular beam epitaxy.The Rutherford back scatteringmeasurements show a minimum channeling yield X_(min) of 3%, which verifies the good crystal-linity of the Si MBE layer.Silicon-on-insulator (SOI) structures have been obtained by succes-sive lateral oxidation of porous-Si.