應用田口法之低介電常數材料(掺碳氧化矽)研究

Abstract

本研究採用田口實驗設計法，分析開發中之低介電常數材料特性，快速掌握影響材料性質之因素，並可獲得較穩定之材料性質。以旋轉塗佈法中兩階段轉速、三階段烘烤溫度、烘烤時間、固化溫度及固化時間共八個因子，配合L18直交表之設計，分析摻碳氧化矽低介電薄膜製程之最佳化參數。 本研究以材料之介電常數及硬度為目標，提升材料之特性與穩定性。在望小法則中，各因子之響應分析顯示八個實驗控制參數中，固化 (curing) 溫度對介電常數影響最大，選擇450oC之確認實驗顯示，其介電常數可達到2.54，硬度為1.07GPa。在望大法則之分析中，第二階段轉速對硬度影響最大，選擇3000rev/min之確認實驗中，硬度可以達到1.73GPa，介電常數為2.83。經過各因子之響應分析，八個實驗控制參數中，固化 (curing) 溫度與第二階段轉速，這兩個因子對介電常數與硬度值均有較重要影響。

In microelectronics industry, the scaling down of devices and the increase of integration seriously raise the RC delay. In this study, the Taguchi method is applied to study the low dielectric constant material, carbon-doped silicon oxide. In spin-on deposition process, we analyze 8 factors (2 stage spin-rate, 3 stage baking temperature, baking time, curing temperature and curing time) for L18 orthogonal array to optimize the film properties. We focused on the dielectric constant and the hardness. The smaller-the-better analysis revealed that the curing temperature played the most important role in improving the dielectric constant. The subsequent confirmation experiment selecting curing temperature at 450oC yielded the dielectric constant 2.54 and the hardness 1.07 GPa. The larger-the-better analysis indicated that the second-stage spin-rate was most critical to improve the hardness. The subsequent confirmation experiments selecting 3000rev/min yielded the hardness 1.73GPa and the dielectric constant 2.83. The responses of the 8 experiment factors revealed that both the curing temperature and the second-stage spin-rate were the most contributed experiment parameters.