每块裸片
测试成本为$0.18,而基于MEMS的
探针卡的每块裸片测试成本为$0.28证明。

图2、较小批量测试时,直到测试量超过一百万片以后,才出现每块裸片测试成本的区别。但对于120万及以后的裸片,总测试成本节约和每张裸片测试成本的差别都很明显。
研究模型结果的另一种方法是研究产品寿命期内的总测试成本。上述大批量情形的模拟结果如图3所示,该图表明延长使用寿命和降低维护成本可以降低探针卡的相关成本,使之从总测试成本的主要部分成为测试时间成本或取决于自动测试仪器(ATE)成本的一小部分。

图3、利用已有的探针卡技术,探针卡成本往往占据总测试成本的大部分。利用Accumax探针卡延长使用寿命和降低维护成本,可转化为更低的总测试成本和降低探针卡在测试成本中的比重。
正如汽车贸易中所说,“各人体会可能不同”。但是ISMI模型清楚证明了我们的假设,充分降低探针测试成本的最好方法,是着重购买具有长寿命和可现场维护的探针卡,其次才是致力于优化晶圆测试工艺以获得最佳结果。
Author Information :
Ron Leckie is President of Infrastructure Advisors, an independent analysis and consulting firm with expertise in technology and marketing within the semiconductor, semiconductor capital equipment and related industries. Prior to starting his consulting practice in 1995, Leckie gained his engineering and manufacturing experience within the semiconductor industry and his system-level development and marketing experience in the capital equipment industry. He is a member of the board of directors of Wentworth Laboratories Inc. (Brookfield, Conn.) and also a board member at Delphon Industries LLC (Hayward, Calif.).