论文标题
通过微秒紫外线激光退火在砷离子植入的硅 - 固定剂中的固体再结晶
Solid Phase Recrystallization in Arsenic Ion-Implanted Silicon-On-Insulator by Microsecond UV Laser Annealing
论文作者
论文摘要
紫外线激光退火（UV-LA）使表面占地的高温热处理能够在新兴的单层堆叠设备中形成突然的连接，其中适用的热预算受到限制。在这项工作中，进行UV-LA进行重新生长，以通过砷离子植入和激活掺杂剂的形式重新生长硅在绝缘子中的晶圆。在微秒（10^-6至10^-5 s）的UV-LA过程中，可以证明单晶固相结晶和掺杂剂的掺杂剂激活，从而在低热预算整合流中开放了各种应用。但是，仍然存在一些担忧。首先，表面形态在再生后降解，这可能是由于使用的激光束的不完美均匀性和/或在表面附近涉及多余掺杂剂的表面形成。其次，许多掺杂剂是不活跃的，似乎在SI带隙中形成了深度水平，这表明对离子植入条件进行了进一步优化，以控制初始晶体损伤和加热剖面，以更好地将掺杂剂适应掺杂剂进入替代部位。
UV laser annealing (UV-LA) enables surface-localized high-temperature thermal processing to form abrupt junctions in emerging monolithically stacked devices, where the applicable thermal budget is restricted. In this work, UV-LA is performed to regrow a silicon-on-insulator wafer partially amorphized by arsenic ion implantation as well as to activate the dopants. In a microsecond scale ( 10^-6 s to 10^-5 s) UV-LA process, monocrystalline solid phase recrystallization and dopant activation without junction deepening are evidenced, thus opening various applications in low thermal budget integration flows. However, some concerns remain. First, the surface morphology is degraded after the regrowth, possibly because of the non-perfect uniformity of the used laser beam and/or the formation of defects near the surface involving the excess dopants. Second, many of the dopants are inactive and seem to form deep levels in the Si band gap, suggesting a further optimization of the ion implantation condition to manage the initial crystal damage and the heating profile to better accommodate the dopants into the substitutional sites.
