用散射光测量正弦表面粗糙度参数的反计算问题

A Inverse Calculation Problem of Sinusoidal Surface Roughness Parameters by Usimg the Scattering Light

本文利用光的角散射分布技术,一般性地解决了正弦表面粗糙度参数的反计算问题。其方法是首先利用 P.Beck-mann 提出的光散射标量理论,计算出光的角散射分布光强。根据光栅方程,得到表面轮廓的平均波长λ_(?);根据角散射分布光强的标准偏差σ,找到了平均斜率Δ_(?)与σ之间的关系,从而得到Δ_(?)的反计算值;再由Δ_(?),λ_(?)与平均粗糙度 R_(?)之间的关系,确定 R_(?)的反计算值。仿真结果表明了该方法的正确性,本文的结果对解决表面粗糙度参数的反计算问题作了有益的探索。

By using the light angular scattering distribution measurement technique,this paper hassolved a inverse calculation problem of sinusoidal surface roughness parameters.In accordance withP.Beckmann's scalar theory of light scattering,the angular scattering distribution curve is obtained.Firstly,using the grating equation,we can obtain surface roughuess parameter λ_(?)(λ(?) is the averagewave length of a profile).Secondly,calculating the value of standard deviation of light angular distri-bution,σ,we find that the ralation between ⊿_α(⊿_α is the arithmatical mean slope of a profile)and σis linear.Thus we arrive at the estimation of the parameter ⊿_α.Finally,according to the rations a-mong λ_(?),⊿_(?) and R_(?)(R_(?) is the arithmetical mean deviation of a profile).We can obtain inverse calcula-tion value of R_α.The result of the simulation indicates that the method is effective.It is of essentialsignificance for us to solve enventually the inverse calculation problem of surface roughness parame-ters.