2L10-252696-11
RING,FOCUS 314-T5G78 LAB

TEL focus ring (OEM P/N 2L10-252696-11), edge-etch confinement ring for Tokyo Electron 300 mm plasma etch systems

ESCT P/N ES7099-210, second-source new focus ring for TEL 300 mm etch process chambers

The TEL focus ring identified by the raw catalogue designation “RING, FOCUS 314-T5G78 LAB” is a circumferential consumable that sits around the perimeter of the electrostatic chuck inside a Tokyo Electron 300 mm plasma etch chamber. Its job is to extend the plasma sheath and the electric field outward beyond the physical edge of the 300 mm wafer, so that the outermost die see the same ion energy and ion-flux geometry as die at the centre of the substrate. Without this ring, the sheath would curve sharply downward at the wafer edge, tilting ion trajectories and ruining edge-zone etch results.

As a directly plasma-exposed part, the focus ring is one of the highest-turnover consumables in any TEL etch toolset. It is bombarded continuously by energetic ions and reactive radicals, and it erodes on a predictable schedule. Because its dimensions and electrical properties drift as it wears, the ring is treated as a yield-critical maintenance item rather than a permanent fixture, and process engineers track its accumulated RF hours closely.

This listing covers a second-source, new equivalent to TEL OEM part number 2L10-252696-11, supplied by ESCT Fab Support under part number ES7099-210. It is built to match the original component in form, fit and function so it can drop into the same chuck assembly position without process re-qualification beyond a fab’s normal incoming-part checks.

Functional role of the focus ring in TEL 300 mm etch platforms

The focus ring performs several interlocking electrical and geometric functions at the wafer edge, all of which directly influence how uniformly the chamber etches the outer annulus of every wafer it processes.

• Extends the plasma sheath radially outward so the electric field above the wafer edge stays vertical, keeping ion incidence near-normal across the full 300 mm diameter.
• Confines and shapes the plasma at the chuck perimeter, defining where the active discharge ends and protecting the chuck edge from direct attack.
• Couples RF energy at the wafer edge so the edge-zone bias and self-bias voltage mirror the centre, equalising ion energy across the substrate.
• Provides a sacrificial erosion surface that takes ion bombardment in place of the chuck and adjacent hardware, localising consumption to a replaceable part.
• Helps establish the gas-flow and by-product residence geometry at the edge, influencing local etch rate and polymer deposition.
• Maintains a consistent edge thermal boundary so the wafer rim is not subjected to a different temperature regime than its interior.

Material and process performance

Focus rings for 300 mm etch chambers are manufactured from carefully selected plasma-resistant materials, because the ring’s chemistry, purity and electrical behaviour become part of the process. The wrong material or a contaminated surface translates directly into particles, metal contamination or drifting etch results.

Material composition and plasma resistance

Depending on the recipe the chamber runs, focus rings of this type are produced from high-purity silicon, silicon carbide or quartz, each chosen for a specific erosion rate and chemical compatibility with the etch chemistry. The second-source ES7099-210 is made to the same material class as the OEM part so its sputter yield and by-product chemistry stay within the process window.

• High material purity to avoid introducing metallic or particulate contamination into the etch chemistry.
• Controlled bulk resistivity so the ring couples RF predictably and reproduces the OEM edge-bias behaviour.
• A defined erosion rate that gives a predictable, schedulable service life rather than erratic end-of-life behaviour.

Dimensional precision and surface finish

Ring height, inner diameter, flatness and surface finish are all process-critical. A height or step that deviates from specification changes the sheath geometry at the wafer edge, while a rough or damaged surface sheds particles and erodes unevenly.

• Tight tolerance on height and inner diameter to preserve the original sheath and field geometry at the edge.
• High flatness so the ring seats evenly on the chuck and maintains uniform RF and thermal contact.
• A controlled surface finish that minimises particle generation and supports even, predictable erosion.

Impact on tool performance and yield

Because the focus ring governs conditions in the outermost annulus of the wafer, its condition maps almost one-to-one onto edge-die yield. A worn or out-of-spec ring shows up first as edge-zone process drift long before it causes an outright fault.

• Edge-to-centre etch-rate and critical-dimension uniformity, which determine how many edge die remain inside specification.
• Etch profile and sidewall angle at the wafer edge, where sheath tilt from a worn ring causes feature lean.
• Particle performance, since an eroded or chipped ring becomes a defect source that drives down die yield.
• Process repeatability between preventive-maintenance cycles and from one chamber to another within a matched toolset.
• Effective wafer throughput, because unplanned ring-related excursions force unscheduled chamber downtime and requalification.

Common wear and failure modes

Progressive erosion and height loss

Continuous ion bombardment steadily sputters material from the ring, reducing its height over time. As the ring thins, the sheath profile at the wafer edge changes, ion tilt increases and edge critical dimensions drift. This is the normal end-of-life mechanism and the reason the ring is tracked against an RF-hour or wafer-count budget.

Cracking, chipping and particle generation

Thermal cycling, mechanical handling and localised hot spots can crack or chip a ceramic or silicon ring, especially as it thins near end of life. Fragments and flakes become particle sources that land on wafers, and a cracked ring can change RF coupling abruptly, producing a sudden process excursion rather than gradual drift.

Surface roughening and deposition build-up

Repeated exposure roughens the ring surface and allows polymer and etch by-products to accumulate. The altered surface chemistry shifts local etch behaviour, and built-up films can later flake away as defects, so deposition state is checked at every preventive-maintenance inspection.

Installation and replacement guidance

Focus-ring replacement is a routine preventive-maintenance task, but it must be carried out under proper contamination control because the ring sits directly in the process path. Always follow the TEL maintenance procedure and the host fab’s safety rules for the specific chamber.

• Place the chamber in maintenance mode, vent it safely, and confirm RF power and gas supplies are locked out and the chuck has cooled.
• Wear clean-room gloves and use clean tools to lift out the worn ring, taking care not to scrape the chuck or adjacent hardware.
• Inspect the chuck seating surface and edge components, cleaning away any deposits or particles before fitting the new ring.
• Unpack ES7099-210 only when ready to fit it, handling it by the edges and checking for shipping damage, chips or contamination.
• Seat the new ring flat and concentric in its location so it sits evenly with full, uniform contact to the chuck.
• Close and pump down the chamber, run the required leak check and seasoning or conditioning recipe, then reset the ring-life counter.
• Verify edge uniformity and particle performance with a qualification wafer before returning the chamber to production.

Spare parts strategy for TEL 300 mm etch consumables

Focus rings are consumed continuously, so a dependable, cost-effective second source protects both budget and uptime. ESCT Fab Support supplies ES7099-210 as a qualified alternative to the TEL OEM ring, giving fabs flexibility without compromising on fit or process behaviour.

• New, second-source part verified to the form, fit and function of OEM P/N 2L10-252696-11.
• A typical lead time of 4–5 weeks, supporting planned preventive-maintenance scheduling and buffer-stock holding.
• Cost relief on a high-turnover consumable that is replaced repeatedly over a chamber’s life.
• A single point of contact for TEL 300 mm etch consumables including focus rings, edge rings and electrode parts.
• Consistent material and dimensional quality to keep edge-etch performance repeatable across replacements.

Frequently asked questions

What does this focus ring actually do in the chamber?

It surrounds the wafer on the electrostatic chuck and extends the plasma sheath and electric field beyond the wafer edge. This keeps ion trajectories vertical and ion energy uniform right out to the 300 mm rim, so the outermost die etch the same as die at the centre.

Is this an original TEL OEM part?

No. ES7099-210 is a second-source, new part built to be compatible with TEL OEM part number 2L10-252696-11. It is not an original OEM component and is not sold as one; it is an equivalent verified to match the original in form, fit and function.

How often does a focus ring need replacing?

Service life depends on the recipe, power levels and accumulated RF hours, so it varies by process. Most fabs track the ring against a defined RF-hour or wafer-count budget and replace it on a scheduled preventive-maintenance cycle before erosion pushes edge results out of specification.

How do I know the ring is worn out?

The usual signs are edge-zone etch-rate or critical-dimension drift, rising edge particle counts, and visible height loss, roughening or chipping at inspection. Reaching the tracked RF-hour limit is itself a trigger to replace the ring even before measurable drift appears.

Will fitting this ring require process re-qualification?

Because it matches the OEM dimensions and material class, it installs in the same position and should not require process changes beyond a fab’s standard incoming-part checks. Most sites run their normal post-PM seasoning and a qualification wafer to confirm edge uniformity and particle performance before resuming production.

What is the lead time and what is included?

The typical lead time is 4–5 weeks. The supplied item is the new second-source focus ring (ES7099-210); contact ESCT Fab Support to confirm current availability, quantities and any buffer-stock arrangements for your TEL etch toolset.

Summary

The TEL focus ring (OEM P/N 2L10-252696-11, ESCT P/N ES7099-210) is a plasma-exposed edge consumable that controls sheath geometry, RF coupling and ion uniformity at the wafer edge in Tokyo Electron 300 mm etch chambers. Its condition directly drives edge-die yield, particle performance and process repeatability, and it wears predictably through erosion, cracking and surface change. Supplied as a new, second-source equivalent on a 4–5 week lead time, ES7099-210 gives fabs a cost-effective, form-fit-function alternative for keeping etch chambers in qualified, repeatable condition.

Disclaimer: This part is supplied by ESCT Fab Support as a new, OEM-compatible second-source component, verified to the form, fit and function of Tokyo Electron part number 2L10-252696-11. It is not an original OEM part and is not sold as one. It is not manufactured by, endorsed by, or affiliated with Tokyo Electron, and all manufacturer names and part numbers are quoted for identification and compatibility purposes only.

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