Recently, a research team composed of engineers from Stanford University, Carnegie Mellon University, University of Pennsylvania, and MIT announced a major breakthrough.Successfully manufactured the first monolithic 3D integrated circuit prototype produced in a commercial foundry in the United States.This prototype chip breaks the traditional two-dimensional layout and uses a single continuous process to directly stack memory and logic circuits vertically together.
It is manufactured using SkyWater's mature 90nm to 130nm process on its 200mm production line and integrates traditional silicon CMOS logic circuits, resistive RAM layers and carbon nanotube field effect transistors.
In this way, the data path between the storage unit and the computing unit is significantly shortened, thereby significantly improving performance.
Early hardware testing results published by the research team show that the stacked structure improves throughput by about four times compared to comparable 2D implementations with similar latency and size.
In addition to the measured hardware, higher-stack architectures were evaluated through simulation, and the results showed that designs with more memory and computing layers can improve performance by up to 12 times in AI workloads.
The team further pointed out that by continuing vertical integration rather than blindly reducing transistor size, the architecture is expected to ultimately achieve a 100- to 1,000-fold improvement in energy-delay product (a combined measure of speed and efficiency).
While academic labs have previously demonstrated experimental 3D chips, the team emphasizes that the biggest difference with this work is that it was fabricated in a commercial foundry environment rather than a custom research production line.
