A 16-GB 640-GB/s HBM2E DRAM with a Data-Bus Window Extension Technique and a Synergetic On-Die ECC Scheme

Circuit and design techniques are presented for enhancing the performance and reliability of a 3-D-stacked high bandwidth memory-2 extension (HBM2E). A data-bus window extension technique is implemented to cope with reduced clock cycle time ranging from data-path architecture, through-silicon via (TSV) placement, and TSV-PHY alignment. A power TSV placement in the middle of array and at the chip edge along with a dedicated top metal for power mesh improves power IR drop by 62%. An on-die ECC (OD-ECC) scheme featuring a self-scrubbing function is designed to be orthogonal to system ECC. An uncorrectable bit error rate (UBER) is improved by 105 times with the proposed OD-ECC and scrubbing scheme. A memory built-in self-test (MBIST) block supports low-frequency cell and core test in a parallel manner and all channel at-speed operation with adjustable ac parameters. The proposed parallel-bit MBIST reduces test time by 66%. A 16-GB HBM2E fabricated in the second generation of 10-nm class DRAM process achieves a bandwidth up to 640 GB/s (5 Gb/s/pin) and provides a stable bit-cell operation at a high temperature (e.g., 105 ° C).