蒙特卡罗模拟Si^＋注入Si3N4／GaAs的射程分布和损伤分布

Monte-Carlo simulation of Si￣+ ion implantation in Si_3N_4/GaAs

用蒙特卡罗方法模拟Ｓｉ＋注入Ｓｉ３Ｎ４／ＧａＡｓ的力学运动，以考察沉积在ＧａＡｓ材料表面的无定形Ｓｉ３Ｎ４阻挡层对Ｓｉ＋射程分布的影响．模拟计算和实验结果都表明，Ｓｉ３Ｎ４阻挡层能够有效地削减Ｓｉ＋在ＧａＡｓ衬底中的射程，避免沟道效应，得到浅结。但是阻挡层中也有相当数量的Ｓｉ、Ｎ原子由于与入射的Ｓｉ＋相互碰撞反冲进入ＧａＡｓ衬底。

Monte-Carlo computer simulations based on the binary collision approximation have been employed to study the range profiles of energetic Si+ ion implantation in Si3N4/GaAs targets. Both the simulations and the experiments showed that a layer of Si3N4 deposited on the surface of GaAs substrate would reduce the range of Si+ ions in GaAs substrate effectively, but a lot of St and N atoms in the Si3N4 layer moved into GaAs substrate due to collision with the incident Si+ ions. Deposition of a layer of amorphous Si3N4 on the GaAs crystal surface followed by high energy ion implatation is a good method to obtain shallow junction and to avoid channeling effects.