1. A method for monitoring fabrication parameters applicable in semiconductor manufacturing, the method comprising the following steps: obtaining a normal parameter variance curve and a comparing parameter variance curve; defining a plurality of normal parameter points on the normal parameter variance curve; defining a plurality of comparing parameter points on the comparing parameter variance curve; finding the corresponding comparing parameter points nearest to the normal parameter points; calculating distances between the normal parameter points and the corresponding comparing parameter points thereof; summing up the distances so as to receive a total distance; and determining whether or not the total distance exceeds a limit.