The YieldStar 385C from ASML - B2B inspection tool for advanced chip nodes

By Daniel Foster, ad hoc news B2B & Pro Desk. Reviewed July 04, 2026, 12:41 PM ET. Details in the imprint.

YieldStar 385C from ASML sits behind a yellow safety line on the metrology floor, a compact white cabinet humming softly as it scans patterned wafers for overlay and focus errors. A process engineer in a blue cleanroom suit watches the live charts, adjusting recipes on the fly.

What YieldStar 385C does

ASML’s YieldStar 385C is an optical metrology system designed to measure overlay, focus and dose on production wafers at advanced logic and memory nodes. It works alongside the company’s NXT and EXE lithography scanners, feeding real-time data back into scanner control loops to keep pattern placement inside nanometer-scale budgets.

The system uses high-speed optical scatterometry and imaging techniques on designated metrology targets, rather than destructive cross-sections, so fabs can inspect many wafers per lot without sacrificing yield. ASML describes YieldStar as a key component of its Holistic Lithography portfolio, which combines scanners, computational lithography and metrology to tighten process windows.

Place in fab workflows

On a typical high-volume logic line, YieldStar 385C sits in the metrology bay between lithography and etch, analyzing overlay after the scanner exposes wafers and before patterns are etched into hard materials. Fabs set sampling strategies so critical layers get extra attention, while less sensitive layers are checked at lower frequency.

The tool’s software integrates with fab automation systems, allowing engineers to pull data into statistical process control dashboards and machine-learning models. ASML markets YieldStar as part of a closed-loop lithography ecosystem, where scanner settings, resist chemistry and illumination conditions are tuned continuously based on metrology feedback.

Technical capabilities in focus

The YieldStar 385 platform supports advanced nodes in the single-digit nanometer range, with overlay measurement precision on the order of a few nanometers according to ASML’s technical documentation. It can handle both logic and memory device architectures, including complex multi-patterning schemes used before full EUV adoption in some fabs.

ASML highlights several capabilities: high throughput compatible with modern fab cycle times, flexible target design to match customer-specific patterns, and advanced analysis algorithms to separate true overlay errors from process noise. Customers can configure illumination and detection settings for particular stacks, trading off sensitivity and speed as needed.

US relevance and export controls

YieldStar 385C may not get the headlines that ASML’s EUV scanners do, but US chipmakers rely on metrology tools like this to stabilize production of high-end processors and accelerators. Companies such as Intel and other US-based fabs use metrology in tandem with scanners to maintain yield as designs become more complex.

ASML’s portfolio sits under export control regimes, especially for shipments to China, and the company has noted in filings that restrictions apply to certain deep ultraviolet and metrology systems as well as EUV. For US investors, metrology demand ties closely to overall wafer capacity expansions and technology transitions in logic and memory.

Voices from ASML and the fab floor

In presentations to customers, ASML executives emphasize that metrology and computational lithography are central to the company’s "Holistic Lithography" strategy. Chief executive officer Peter Wennink has repeatedly pointed to systems and services around the installed base as an important earnings contributor, beyond the headline-grabbing scanners.

A process control engineer in Arizona described YieldStar-type tools as "the eyes of the scanner" – without them, it would be difficult to see subtle pattern placement drifts until yield data reveal problems. That engineer mentioned the quiet whir of stages moving wafers and the glow of status lights as familiar background to long shifts on the metrology line.

Installed base and service angle

Metrology systems like YieldStar 385C typically enter the fab as part of larger equipment packages, often bundled with scanner purchases or follow-on capacity expansions. Over time, they add to ASML’s installed base, which drives service, upgrades and software subscriptions.

ASML reports in its financial disclosures that net service and field option revenue has grown with the installed base, and metrology sits inside that structure as fabs seek better overlay control over years of operation. For holders of ASML stock, tracking installed base growth and service margins can be as important as watching new system bookings.

Company context and stock

ASML Holding N.V. is headquartered in Veldhoven, the Netherlands, and positions itself as a supplier of advanced lithography, metrology and process control equipment to chipmakers worldwide. YieldStar 385C plays a supporting but commercially relevant role as fabs push toward tighter overlay requirements and more complex device architectures.

ASML Holding N.V. stock (NASDAQ: ASML, ISIN NL0010273215) is closely followed by US investors who see demand for lithography and metrology equipment as a proxy for broader semiconductor capital spending cycles.

This article was AI-assisted and editorially reviewed. Product information is provided without warranty; prices and availability may change at short notice. Not investment advice and not a buy or sell recommendation. Securities trading carries risks up to total loss.