光谱学与光谱分析
光譜學與光譜分析
광보학여광보분석
SPECTROSCOPY AND SPECTRAL ANALYSIS
2014年
5期
1163-1167
,共5页
刘华松%姜承慧%王利栓%刘丹丹%姜玉刚%孙鹏%季一勤
劉華鬆%薑承慧%王利栓%劉丹丹%薑玉剛%孫鵬%季一勤
류화송%강승혜%왕리전%류단단%강옥강%손붕%계일근
HfO2 薄膜%Ta2 O5 薄膜%光学常数%物理模型
HfO2 薄膜%Ta2 O5 薄膜%光學常數%物理模型
HfO2 박막%Ta2 O5 박막%광학상수%물리모형
HfO2 films%Ta2 O5 films%Optical constants%Physical model
采用离子束溅射(IBS)方法制备了 HfO2和 Ta2 O5两种金属氧化物薄膜,通过测量薄膜的椭偏参数,使用非线性最小二乘法反演计算获得薄膜的光学常数。在拟合过程中,采用L8(27)正交表设计了8组反演计算实验,在初始选定Cauchy模型后,对 HfO2薄膜拟合影响最大的为表面层模型,对Ta2 O5薄膜拟合影响最大的为折射率梯度模型。确定了不同物理模型对拟合函数MSE的影响权重和拟合过程中模型选择的次序,按照确定的模型选择次序拟合,最后加入弱吸收模型反演计算两种薄膜的光学常数,反演计算的MSE相对初始MSE可下降79%和39%,表明拟合过程模型选择物理意义明确,具有广泛的应用价值。在500 nm处,Ta2 O5薄膜的折射率梯度大于HfO2薄膜,而HfO2薄膜消光系数大于Ta2 O5薄膜。表明 Hf金属与Ta金属相比容易氧化形成稳定的氧化物,HfO2薄膜的吸收要高于Ta2 O5薄膜。
採用離子束濺射(IBS)方法製備瞭 HfO2和 Ta2 O5兩種金屬氧化物薄膜,通過測量薄膜的橢偏參數,使用非線性最小二乘法反縯計算穫得薄膜的光學常數。在擬閤過程中,採用L8(27)正交錶設計瞭8組反縯計算實驗,在初始選定Cauchy模型後,對 HfO2薄膜擬閤影響最大的為錶麵層模型,對Ta2 O5薄膜擬閤影響最大的為摺射率梯度模型。確定瞭不同物理模型對擬閤函數MSE的影響權重和擬閤過程中模型選擇的次序,按照確定的模型選擇次序擬閤,最後加入弱吸收模型反縯計算兩種薄膜的光學常數,反縯計算的MSE相對初始MSE可下降79%和39%,錶明擬閤過程模型選擇物理意義明確,具有廣汎的應用價值。在500 nm處,Ta2 O5薄膜的摺射率梯度大于HfO2薄膜,而HfO2薄膜消光繫數大于Ta2 O5薄膜。錶明 Hf金屬與Ta金屬相比容易氧化形成穩定的氧化物,HfO2薄膜的吸收要高于Ta2 O5薄膜。
채용리자속천사(IBS)방법제비료 HfO2화 Ta2 O5량충금속양화물박막,통과측량박막적타편삼수,사용비선성최소이승법반연계산획득박막적광학상수。재의합과정중,채용L8(27)정교표설계료8조반연계산실험,재초시선정Cauchy모형후,대 HfO2박막의합영향최대적위표면층모형,대Ta2 O5박막의합영향최대적위절사솔제도모형。학정료불동물리모형대의합함수MSE적영향권중화의합과정중모형선택적차서,안조학정적모형선택차서의합,최후가입약흡수모형반연계산량충박막적광학상수,반연계산적MSE상대초시MSE가하강79%화39%,표명의합과정모형선택물리의의명학,구유엄범적응용개치。재500 nm처,Ta2 O5박막적절사솔제도대우HfO2박막,이HfO2박막소광계수대우Ta2 O5박막。표명 Hf금속여Ta금속상비용역양화형성은정적양화물,HfO2박막적흡수요고우Ta2 O5박막。
In the present paper ,two metal oxide films of HfO2 and Ta2 O5 were prepared by ion beam sputtering technology . Through measuring ellipsometric parameters of HfO2 and Ta2 O5 films ,their optical constants can be inversion-calculated by non-linear least squares techniques .In the fitting process ,eight experiment groups were arranged by the orthogonal table L8 (27 ) . After selecting Cauchy model ,the largest influencing factor for fitting optical constant of HfO 2 is surface layer model and the lar-gest influencing factor for fitting optical constant of Ta2 O5 is refractive index gradient model .The impact of different physical model on MSE and the order for selecting model in the fitting process are determined .According to the selecting model and the determined fitting order ,optical constants of the two metal oxide films were inversion-calculated with adding weak absorption model ,and the obtained MSE can descend 79% and 39% according to the initial value .The results indicated that the selecting model possesses definite physical significance in the fitting process .The obtained method can be applied in inversion-calculating many metal oxide films with weak absorption .It has wide application value .At 500 nm ,the refractive index gradient of Ta2 O5 films is greater than HfO2 films ,while the extinction coefficient of HfO2 films is greater than Ta2 O5 .It was shown that Hf met-al is easier to form stable oxide than Ta metal .And the absorption of HfO2 films is larger than Ta2 O5 films .