Failure bitmap compression method for 3D-IC redundancy analysis

As the chance of memory faults has increased, many redundancy analysis (RA) techniques are widely used in order to gain a proper manufacturing yield. To find appropriate repair solutions, the external automatic test equipment (ATE) receives the faulty information and stores it into a 2-D failure bitmap. This paper presents a new failure bitmap compression method which utilizes modified run-length codes. The proposed idea can reduce hardware overhead of a failure bitmap while preserving all the faulty information that is needed to get optimal repair rate. Experimental results show that the proposed method can obtain more than 80% of reduction rate in the failure bitmap size.