Due to globalization in the semiconductor supply chain, counterfeit dynamic random-access memory (DRAM) chips/modules have been spreading worldwide at an alarming rate. Deploying counterfeit DRAM modules into an electronic system can severely affect security and reliability domains because of their sub-standard quality, poor performance, and shorter life span. Besides, studies suggest that a counterfeit DRAM can be more vulnerable to sophisticated attacks. However, detecting counterfeit DRAMs is very challenging because of their nature and ability to pass the initial testing. In this paper, we propose a technique to identify the DRAM origin (i.e., the origin of the manufacturer and the specification of individual DRAM) to detect and prevent counterfeit DRAM modules. A silicon evaluation shows that the proposed method reliably identifies off-the-shelf DRAM modules from three major manufacturers.
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DRAM Retention Behavior with Accelerated Aging in Commercial Chips
The cells in dynamic random access memory (DRAM) degrade over time as a result of aging, leading to poor performance and potential security vulnerabilities. With a globalized horizontal supply chain, aged counterfeit DRAMs could end up on the market, posing a significant threat if employed in critical infrastructure. In this work, we look at the retention behavior of commercial DRAM chips from real-time silicon measurements and investigate how the reliability of DRAM cells degrade with accelerated aging. We analyze the retention-based errors at three different aging points to observe the design-induced variations, analyze the pattern dependency, and explore the impacts of accelerated aging for multiple DRAM vendors. We also investigate the DRAM chips’ statistical distribution to attribute the vital wear-out effects present in DRAM. We see a continuous increase in retention error as DRAM chips age and therefore infer that the aged retention signatures can be used to differentiate recycled DRAM chips in the supply chain. We also discuss the roles of device signature in DRAM aging and aging-related security implication on DRAM row-hammer error.
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- PAR ID:
- 10393051
- Date Published:
- Journal Name:
- Applied Sciences
- Volume:
- 12
- Issue:
- 9
- ISSN:
- 2076-3417
- Page Range / eLocation ID:
- 4332
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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