Since the redundancy analysis (RA) has been introduced for memory yield, many RA researches have been conducted. However, objective comparisons of them are difficult by the absence of real memory models with realistic fault distributions. This paper presents a fail memory configuration set for RA estimation, called as ITC'2020 RA Benchmarks. It enables objective estimations of RAs with respect to effectiveness and efficiency. The fail memory configuration set includes memory models which have various redundancy structures and a fault generation algorithm with fault distribution which can be criteria for objective comparisons of RA. Simulations for estimations and comparisons of RA researches including BIRA are progressed utilizing the fail memory configuration set.

This paper presents a method for the evaluation of the eye diagram of a signal by analyzing the atypical Shmoo plot extracted from an automatic test equipment using a loopback technique. The loopback technique was used to minimize the external noise generated by an oscilloscope, thereby making it easier to measure the signals and collect raw data. In addition, the Shmoo plot extracted using a shorting package enables analyses of the signals entering the device in actual situations. Subsequently, an analysis tool was developed to investigate characteristics of the extracted atypical Shmoo plot, such as jitter, rise and fall time, and signal data rate. Furthermore, this tool indicates the signal loss rate for all the pass zones and center point deviations in the eye diagram. The analysis tool produces an eye diagram from the extracted Shmoo plot to determine the signal quality status and also statistically analyzes the extracted raw data to determine the process capability of the automatic test equipment.

As memory capacity and density grow, a corresponding increase in the number of defects decreases the yield and quality of embedded memories for systems-on-chip as well as commodity memories. For embedded memories, built-in redundancy analysis (BIRA) is widely used to solve quality and yield issues by replacing faulty cells with healthy redundant cells. Many BIRA approaches require extra hardware overhead in order to achieve optimal repair rates, or they suffer a loss of repair rate in minimizing the hardware overhead. An innovative BIRA approach is proposed to achieve optimal repair rates, lower area overhead, and increase analysis speed. The proposed BIRA minimizes area overhead by eliminating some storage coverage for only must-repair faulty information. The proposed BIRA analyzes redundancies quickly and efficiently by evaluating all nodes of a branch in parallel with a new analyzer which is simple and easy-to-implement. Experimental results show that the proposed BIRA allows for a much faster analysis speed than that of the state-of-the-art BIRA, as well as the optimal repair rate, and relatively small area overhead.

With the growth of memory capacity and density, test cost and yield improvement are becoming more important. In the case of embedded memories for systems-on-a-chip (SOC), built-in redundancy analysis (BIRA) is widely used as a solution to solve quality and yield issues by replacing faulty cells with extra good cells. However, previous BIRA approaches focused mainly on embedded memories rather than commodity memories. Many BIRA approaches require extra hardware overhead to achieve the optimal repair rate, which means that 100% of solution detection is guaranteed for intrinsically repairable dies, or they suffer a loss of repair rate to minimize the hardware overhead. In order to achieve both low area overhead and optimal repair rate, a novel BIRA approach is proposed and it builds a line-based searching tree. The proposed BIRA minimizes the storage capacity requirements to store faulty address information by dropping all unnecessary faulty addresses for inherently repairable die. The proposed BIRA analyzes redundancies quickly and efficiently with optimal repair rate by using a selected fail count comparison algorithm. Experimental results show that the proposed BIRA achieves optimal repair rate, fast analysis speed, and nearly optimal repair solutions with a relatively small area overhead.