【摘要】 利用扫描隧道显微镜 ( STM)等分析手段 ,我们对 Si( 1 1 1 )在 NH3气氛下氮化后的表面结构进行了研究 .Si( 1 1 1 )在 1 0 75K暴露于 NH3后 ,表现所形成的氮化硅存在周期为 1 .0 2 nm的(“8/3× 8/3”)再构 ,当温度提高到 1 1 2 5K以上时 ,表面出现周期为 3.0 7nm的超结构 .这两种表面超结构都可以形成“8× 8”低能电子衍射花样 .系统的研究证明 3.0 7nm超结构是在 Si( 1 1 1 )表面形成晶态 β- Si3N4 薄膜 ( 0 0 0 1 )表面的 4× 4再构 ,而 1 .0 2 nm周期是 Si( 1 1 1 )表面未获得有效氮化的一种结构更多还原

【Abstract】 After exposing Si(111) to NH\-3 at about 1075K,a 1 02nm surface periodic structure (the “8/3×8/3” reconstruction) is observed in the scanning tunneling microscopy (STM) images.When the nitridation temperature is above 1125K,a surface superstructure with a period of 3.07nm is observed. Both of the superstructures induce an “8×8” electron diffraction pattern. Our systematic analyses suggest that the 3.07nm superstructure is the 4×4 reconstruction on the Si\-3N\-4(0001) surface of the crystalline silicon nitride (β\|Si\-3N\-4) thin film formed on Si(111),while the 1.02nm periodic structure is an incomplete nitridation phase on the Si(111) surface.更多还原