圆柱形反应器鞘区离子平均动能的径向分布

The diametric distribution of average kinetic energy of ions the sheath of cylinder chambers

针对鞘层结构,建立了鞘层模型和离子速度分布函数,导出了离子平均动能的积分表达式并得出数值积分的结果.用级数的两项拟合平均动能积分表达式的对数项,积分得到解析结果和简化结果.应用积分表达式、解析式及简化式进行计算,得出了圆柱形鞘层内不同位置(半径)处的粒子平均动能.结果表明鞘层越厚、粒子平均自由路程越小,则它们的差别越小.它们可有效地应用于散布在反应室各处粉体的刻蚀和纯化.

According to the sheath structure, the sheath model and velocity distribution function of the ions were established. The integration formula of the average kinetic energy of the ions was calculated and the numerical integration results were given. Two items of the series fitted with the logarithm in the integration formula were integrated, and an analytical equation and its simplif lished. From the equations above, the average kinetic energy of the ions at the diff ied one were estaberent positions （the diameters） in cylinder chambers were given. The calculated results from three equations showed that the thicker sheath and the smaller average free path of the ions are, the smaller their difference possess. These conclusions could be referred to the etching and purity of particulates spread everywhere in the chambers.