本論文提出一可量測八吋基板薄膜應力的量測系統,以懸臂法作為基礎改良之量測系統,試片以雙電子鎗蒸鍍機進行鍍製,試片完成後以垂直放置的方式固定於載台後,掃描其表面輪廓。觀察掃描點的偏移量,經數學計算後,推得出物體的曲率半徑,進而得到其薄膜應力的數值。量測系統具有即時性、操作簡易等優勢。並以雙電子鎗蒸鍍機鍍製兩高反射鏡,在有限的空間中提升量測系統之精度,並輔以Macleod模擬軟體驗證實驗之結果。;In this thesis, we propose a method measuring thin film stress on 8-inch substrate. The cantilever method is used as the basis for the improvement of the measuring system. We use dual electron beam gun evaporation with ion-beam assisted deposition to evaporate optical thin film on 8-inch substrate. Placing 8-inch substrate on the stage in vertical way and scanning the surface profile. We calculate the deflection of 8-inch substrate according to the displacement of reflection point, and then get the value of the thin film stress. We use Macleod simulation software and other measuring system to verify the results of the experiment. The measuring system has the advantage of instantaneity and easy-use.