Onto Innovation (ONTO) Bets $720M on X-Ray Chip Technology

September 7, 2026 - 09:50

On August 10, Onto Innovation closed a deal to acquire a 27% minority interest in Rigaku Holdings Corporation, paying around $720 million for the shares. The seller was Atom Investment, L.P., an affiliate of Carlyle. This move follows an earlier partnership announced in April, when the two companies agreed to work together on X-ray based tools for process control in semiconductor manufacturing.

The investment gives Onto a significant foothold in a technology that is becoming more critical as chip geometries shrink and new packaging schemes gain ground. X-ray metrology offers advantages for measuring features that are buried or difficult to reach with traditional optical methods. That matters for advanced memory stacks, logic devices with complex interconnects, and high-volume production where tiny variations can cause big yield losses.

Onto's management has framed the deal as a way to accelerate the joint roadmap rather than a purely financial play. The two firms have already been co-developing systems that pair Onto's inspection platforms with Rigaku's X-ray source and detector know-how. With the ownership stake, Onto gets a seat at the table for strategic decisions at Rigaku, which has a long history in analytical instrumentation and a growing portfolio for semiconductor applications.

The transaction also signals that Onto is willing to make large bets on differentiating hardware. The company has been competing in a crowded field of inspection and metrology suppliers, and X-ray based solutions could help it stand out where optical techniques are hitting physical limits. Rigaku, for its part, gains a committed partner with deep ties to chipmakers and a clear view of where the industry is heading.

No changes to Rigaku's management or day-to-day operations were announced as part of the deal. Onto says it will account for the stake under the equity method, meaning it will record its share of Rigaku's earnings rather than consolidate the full results. The companies expect to provide more details on joint product milestones in the coming quarters.