The demand for accurate information about the internal structure and characteristics of dynamic random-access memory (DRAM) has been on the rise. Recent studies have explored the structure and characteristics of DRAM to improve processing in memory, enhance reliability, and mitigate a vulnerability known as rowhammer. However, DRAM manufacturers only disclose limited information through official documents, making it difficult to find specific information about actual DRAM devices. This paper presents reliable findings on the internal structure and characteristics of DRAM using activate-induced bitflips (AIBs), retention time test, and row-copy operation. While previous studies have attempted to understand the internal behaviors of DRAM devices, they have only shown results without identifying the causes or have analyzed DRAM modules rather than individual chips. We first uncover the size, structure, and operation of DRAM subarrays and verify our findings on the characteristics of DRAM. Then, we correct misunderstood information related to AIBs and demonstrate experimental results supporting the cause of rowhammer. We expect that the information we uncover about the structure, behavior, and characteristics of DRAM will help future DRAM research.

翻译：对动态随机存取存储器（DRAM）内部结构和特性的准确信息需求日益增长。近期研究探索了DRAM的结构与特性，以改进内存计算、增强可靠性，并缓解称为行锤攻击（rowhammer）的漏洞。然而，DRAM制造商仅通过官方文档披露有限信息，导致难以获取实际DRAM设备的具体细节。本文利用激活诱导比特翻转（AIBs）、保持时间测试和行复制操作，提出了关于DRAM内部结构和特性的可靠发现。尽管先前的研究尝试理解DRAM设备的内部行为，但要么仅展示结果而未识别原因，要么分析的是DRAM模组而非单个芯片。我们首先揭示了DRAM子数组的尺寸、结构和操作，并验证了关于DRAM特性的发现。随后，我们纠正了与AIBs相关的误解信息，并展示了支持行锤攻击成因的实验结果。我们期望所揭示的DRAM结构、行为及特性信息能助力未来的DRAM研究。