Single spin silicon etching behavior analysis by quality engineering (Taguchi method)

The effective parameters in the single spin silicon etching are examined by the quality engineering method. The concentric zone divided uniformity analysis makes it possible to identify the contributing parameters in the system. Three parameters, wafer spin speed, etching chemical flow rate and chemical dispensing boom swing width are recognized as the main factors which define the etching amount distribution behavior. By controlling these parameters, less than 5% uniformity etching can be achieved from few μm to over 200μm wide range of the etching target.