Students: Angel Chen & Cindy Zhao
Project: Error Protection for Phase Change Memory
Institution: Lehigh University
Major: Electrical & Computer Engineering
Advisor: Xiaochen Guo
Abstract
As Dynamic Random Access Memory (DRAM) is reaching its limit due to scaling issues, there is a need for possible memory alternatives. Phase Change Memory (PCM) is a non-volatile memory that can be a viable alternative. The write endurance and low energy consumption make it a promising candidate over DRAM. However, similar to DRAM, PCM encounters errors that need to be addressed to ensure the same level of reliability as DRAM. Although PCM is not as prone to alpha particle strikes as DRAM is, PCM has other types of errors such as stuck-at fault and thermal crosstalk-induced soft errors.
In this paper, we investigate both soft and hard error rates for PCM. As we continue to scale PCM and minimize the area below 20nm, thermal crosstalk becomes more crucial as a source of
error for both Single-Level Cell (SLC) and Multi-Level Cell (MLC) PCM. We focused our attention on read errors, resistance drifting errors, and thermal crosstalk for soft errors and stuck- at-fault for hard errors. For each type of error, we built an error model. In the end, we combine all types of errors into one comprehensive error model that shows failure over time. With this model, the strength of the error-correcting code (ECC) can be better determined for the best reliability while minimizing storage overhead.
About Angel Chen
Angel Chen is currently a senior studying Computer Engineering. Upon graduation, he will continue his study by pursuing a Masters in Computer Science. Angel has started doing research with Dr. Xiaochen Guo since Fall 2019in the Computer Architecture Lab. His work mostly focuses on studying emerging memory technologies such as Phase Change Memory (PCM) and works to optimize performance and reliability. Aside from research, Angel finds passion in hackathons and has won multiple awards from hackathons such as TreeHacks, PrincetonHacks, and HopHacks. On-campus he demonstrates leadership being the president of the Society of Asian Scientists and Engineers. During his free time, you can find him brushing up on his ping pong skills in Southside Commons.
About Cindy Zhao
Xinhui Zhao is currently a senior studying Electrical Engineering with a minor in German. Xinhui has done research with Dr. Xiaochen Guo since Fall 2018 in the Computer Architecture Lab. As a research assistant in the lab, she designed outreach projects to teach the concepts of spatial and temporal locality of caches. She has worked on enforcing persistent order on the cache to automate cache line write back and is currently working on phase-change memory optimizations. She has a profound interest in Computer Architecture, especially with power consumption and efficiency. Academically she excels and has kept a GPA of 3.94 in her senior year. Outside of class, she participates in SPEAK, Students Promoting Equality, Awareness and Knowledge and Anime club. She shares a passion for Japanese culture, particularly in the film industry.
