In 2019 we wrote about a curious technology demonstration by Arm in collaboration with GlobalFoundries. At the time, the research team announced it has taped out a logic-on-logic 3-dimensional stacked test chip in an attempt to explorer the benefits of 3D integration for stacked logic through the use of a 3D mesh interconnect. Arm hoped the research would reveal the benefits of high-density 3D integration to Arm-based IPs.
The chip - codenamed Trishul - is Arm's first exploratory test chip which demonstrates the feasibility of high-density 3D stacking using Arm IPs. Specifically, Trishul leverages GlobalFoundries 12-nanometer leading-performance (12LP) process technology and relies on their hybrid bonding technology which features sub-10 µm bond pitch.