抄録
Orthogonal array L18 is frequently used in quality engineering. Under normal application,8factors, i.e.,1 two-level factor and 7 three-level factors, are assigned to this array. But it can also be used to assign nine factors, i.e., 1 two-level factor and 8 three-level factors,without being forced to use a larger orthogonal array such as L36. In this paper, analysis method and same hints are explained using a case entitled "Technology Development of Drain Electrode process for Power MOSFET" which was reported earlier in Volume 4, No. 2.