The AI Chip Test Gatekeepers — Every Accelerator Must Pass Through These Machines
Before a single NVIDIA Blackwell, AMD MI400, or Google TPU is shipped, it has to be tested on equipment made by one of two companies. Advantest owns ~70% of that.
Testing a modern AI chip is its own little engineering miracle. The chip has billions of transistors, six to eight HBM stacks, and runs at 1,000+ watts. Each chip is poked by thousands of tiny pins (a "probe card"), fed power, and run through thousands of test vectors — at full speed — to find any bad transistors before the chip is sold. HBM testing is roughly 10x more compute-intensive than regular DRAM testing because the dies are buried inside a 3D stack and have to be tested through the wires that connect them. Two companies dominate: Advantest (Japan, ~70% share in HBM and high-end AI testers) and Teradyne (US, the other half of the test duopoly). Separately, Camtek and Onto Innovation inspect every HBM stack visually with optical metrology.
Every accelerator NVIDIA, AMD, Google, AWS, or Microsoft ships passes through these machines. Each generation of AI chip requires longer test times — Rubin tests take longer than Blackwell, which take longer than Hopper. Advantest is ramping capacity from 3,000 systems in 2024 to 5,000 in 2026 to a target of 10,000 by 2027 just to keep up.
5 names on the watchlist
~70% of HBM/AI tester market. Every NVIDIA Blackwell, AMD MI400, Google TPU, and AWS Trainium tests on its V93000.
Japanese maker of Automated Test Equipment (ATE) . The flagship V93000 platform tests AI SoCs and HBM stacks at speeds the chip will see in the field. Per Chip Stock Investor and multiple analyst reports, Advantest captures ~50-58% of the total ATE market and ~70% in HBM-specific and high-end AI testers. FY26 guide: ¥1,420B revenue, ¥627B operating income.
The "other half" of the test duopoly with Advantest. Magnum EPIC platform is the industry standard for several HBM and custom-ASIC test applications.
US-based ATE leader, also owns Universal Robots (the cobot business — see Robotics sector). Teradyne's Magnum EPIC platform is the industry standard for many HBM testing applications, and Teradyne has gained significant ground at hyperscaler custom-ASIC customers in 2025-26. Stock hit an all-time high of $344.92 in February 2026, up ~245% in 12 months.
Reference tool for HBM4 inspection across all three major manufacturers. Optical metrology for advanced packaging.
Israeli company that makes optical inspection and metrology systems for advanced semiconductor packaging — the "eyes" that check every HBM stack and chiplet before they ship. The flagship Hawk and Eagle GS platforms use 9th-generation white-light triangulation, giving better coverage than laser-based competitors. Per multiple analyst sources, Camtek is the "reference tool" for HBM4 inspection across SK Hynix, Samsung, and Micron.
Optical metrology for advanced packaging — Camtek's most direct competitor with more diversified exposure.
Diversified competitor to Camtek in optical metrology and inspection for advanced packaging. Smaller HBM exposure than Camtek but broader product portfolio across lithography metrology and process control. The way to own this chokepoint without single-tool concentration risk. Lower-beta way to play the same secular trend.
Burn-in / wafer-level stress test — historically SiC-focused, now pivoting to HBM and gallium nitride.
Small-cap, very volatile, single-customer concentration risks. The pivot from SiC burn-in (which slumped with the EV demand softening) to HBM burn-in is what unlocks the next leg if it works. Size very small.
- Bernstein, TrendForce, Counterpoint · May 2026