(Replacement Collisions) TRIM的输出文件SRIM 1 - EAST.PPT

* SRIM ASIPP * 单击处编辑母版标题样式 SRIM SRIM程序介绍 谭模强 2005年6月1日 outline 概括介绍SRIM SRIM的应用 SRIM is a group of programs which calculate the stopping and range of ions into matter。 METHOD ：Using a full quantum mechanical treatment of ion-atom collisions.(SRIM always referes to the moving atom as an ion, and all target atoms as atoms) SRIM consists of two main programs, and several special-purpose programs. SR(Tables of Stopping and Ranges of ions in simple targets). quickly creates Tables of the stopping and range of ions in matter over a wide band of ion energies. TRIM (the Transport of Ions in Matter) is a Monte-Carlo calculation which follows the ion into the target, making detailed calculations of the energy transferred to every target atom collision. (multi-layer complex targets) 　蒙特卡罗模拟方法(M-C 方法) 通过计算机模拟跟踪一大批入射粒子的运动。粒子的位置、能量损失以及次级粒子的各种参数都在整个跟踪过程中存储下来, 最后得到各种所需物理量的期望值和相应的统计误差。在M-C 方法计算过程中采用连续慢化假设, 即入射离子与材料靶原子核的碰撞采用两体碰撞描述, 这一部分主要导致入射离子运动轨迹的曲折, 能量损失来自于弹性能量损失部分, 而在两次两体碰撞之间认为入射离子与材料中的电子作用连续均匀地损失能量, 当入射为重离子时可认为在这期间入射离子作直线运动, 能量损失来自于非弹性能量损失部分。两次两体碰撞之间的距离以及碰撞后的参数通过随机抽样得到。 Monte-Carlo TRIM is very versatile: It will handle ion energies from 10 eV to 2 GeV/amu, and targets with up to eight layers, made up of twelve different elements. It will calculate both the final 3D distribution of the ions and also all kinetic phenomena associated with the ions energy loss: target damage, sputtering, ionization, and phonon production. All target atom cascades in the target are followed in detail. This program is more accurate in calculating ion ranges than the transport program used in the SR program to produce the range tables described above.  Stopping power:入射粒子在单位路程上损失的能量(-dE/dx). Range:入射粒子从进入靶起到停止点所通过的总的路程,称为射程. Projected Range: 以Rp表示射程在入射方向投影的长度,称作投影射程. SRIM相关名词 左边的示意图是一个能量E,有入射角的入射粒子在物质中的轨迹。 是粒子在靶物质中所走过的路程， 是与入射方向平行的射程， 是与入射方向垂直的射程， 与入射表面垂直的射程。 Ion :入射粒子 Atom :靶原子 Recoil atoms: 与入射粒子发生位移碰撞的反冲靶原子 Straggle: 射程是具有统计性质的,不完全一致,而有小的统计变化 C