论文部分内容阅读
本文通过数值方法解浓度相关的扩散方程来研究二维离子注入剖面经热处理后的再分布。掩模边缘可以是离子或化学刻蚀的,而初始剖面可以是高斯或PearsonⅣ型。结果表明,在非理想掩模条件下,硼离子的侧向扩展主要是由工艺的初始条件所决定。侧向扩展的宽度可达到垂直方向的两倍。但是,对于温度低于1200℃及时间少于40秒的热处理,侧向结深的移动是不明显的,因此对于典型快速热退火,侧向结深基本上保持不变。然而,即使在1100℃,30秒的热扩散,垂直方向的结深却增加了5％。
In this paper, the concentration-dependent diffusion equation is solved numerically to study the redistribution of two-dimensional ion implantation profiles after heat treatment. The edge of the mask can be ionically or chemically etched while the initial profile can be Gaussian or Pearson type IV. The results show that under the non-ideal mask conditions, the lateral extension of boron ions is mainly determined by the initial conditions of the process. The width of the lateral expansion can reach twice the vertical. However, for heat treatment at temperatures below 1200 ° C and for less than 40 seconds, the lateral junction depth is not appreciably shifted, so the lateral junction depth remains essentially unchanged for a typical rapid thermal anneal. However, the junction depth in the vertical direction was increased by 5% even with thermal diffusion of 30 seconds at 1100 ° C.