2L10-251409-11
FOCUS RING(LAB),360-T4(320)HS

Focus ring, 360-T4 (320) HS (OEM P/N 2L10-251409-11), edge process consumable for TEL 300 mm plasma etch systems

ESCT P/N ES7099-108 · Tokyo Electron (TEL) compatible focus ring

The Focus Ring 360-T4 (320) HS is a consumable edge-zone component used in Tokyo Electron (TEL) 300 mm plasma etch process chambers. It is the annular ring that surrounds the wafer at the outer perimeter of the electrostatic chuck (ESC), sitting flush against the wafer edge and bridging the discontinuity between the silicon substrate and the surrounding chamber hardware. In TEL etch platforms, this part is one of the highest-turnover consumables in the chamber kit because it sits directly in the plasma sheath and absorbs the bulk of the ion energy that would otherwise erode more costly, longer-lead hardware.

Functionally, the focus ring “focuses” or extends the plasma sheath beyond the physical edge of the wafer so that the electric field lines arriving at the wafer perimeter remain as vertical as they are across the centre. The “360” and “320” descriptors in the part name relate to its dimensional family and inner-diameter geometry tuned to the 300 mm wafer, while the “HS” designation typically denotes a high-performance or hardened variant for more aggressive process recipes. Without a correctly profiled and minimally worn focus ring, etch behaviour in the outer few millimetres of the wafer degrades rapidly.

Because it is sacrificial by design, the focus ring is intended to be replaced on a defined preventive-maintenance cadence rather than run to catastrophic failure. Maintaining a qualified supply of these rings is therefore central to keeping a TEL etch fleet at target uptime and edge yield.

Functional role of the focus ring in TEL plasma etch platforms

The focus ring performs several interlocking roles at the wafer edge, all of which influence how uniformly the plasma processes the outer annulus of the wafer. Its key functions include:

• Extends the plasma sheath radially outward past the wafer edge so the sheath boundary, and therefore the ion trajectories, stay perpendicular to the wafer surface at the perimeter.
• Corrects edge bending of the electric field that would otherwise cause tilted etch profiles, critical-dimension drift and reduced usable area in the outermost dies.
• Provides a controlled electrical and thermal boundary between the biased wafer and the surrounding chamber, shaping the RF return path at the edge.
• Protects the electrostatic chuck, ESC edge and underlying hardware from direct ion bombardment and chemical attack by acting as the sacrificial outer surface.
• Helps confine and stabilise the plasma over the wafer, supporting consistent ion density and reducing arcing at the wafer edge.
• Contributes to particle performance by presenting a clean, smooth and dimensionally stable surface that minimises flaking and redeposition.

Material and process performance

As a sheath-exposed consumable, the focus ring lives or dies on its material properties and dimensional precision. Two performance dimensions matter most: how the material resists the plasma, and how the geometry holds tolerance over the ring’s service life.

Plasma and chemical resistance

Focus rings for TEL etch chambers are produced from process-matched materials selected for low erosion rate and minimal contribution to particle and metals contamination. Common choices, depending on the specific recipe and chamber, deliver the following:

• High-purity silicon or silicon carbide variants that erode predictably and avoid introducing foreign species into the etch chemistry.
• Resistance to fluorine- and chlorine-based plasmas and to the repeated ion bombardment that defines high-density etch processes.
• Controlled resistivity so the ring participates correctly in the edge RF and bias environment rather than distorting it.
• Tight surface-finish control to limit micro-masking, flaking and the generation of adder defects.

Dimensional stability and geometry

The ring’s inner diameter, step height relative to the wafer and overall flatness are tightly toleranced because edge etch behaviour is acutely sensitive to the height of the sheath relative to the wafer surface. A focus ring delivers value through:

• A precisely machined inner profile that matches the 300 mm wafer edge and seats reproducibly on the chuck.
• Flatness and parallelism that keep the sheath height uniform around the full 360° of the wafer edge.
• A predictable, slow erosion signature so the process window can be characterised against ring age.
• Repeatable part-to-part geometry, so a fresh ring restores the qualified baseline rather than shifting the edge process.

Impact on tool performance and yield

Because it governs the edge region, the condition of the focus ring translates directly into measurable fab metrics. The consequences of ring wear or mismatch include:

• Edge critical-dimension and etch-rate drift, eroding within-wafer uniformity and the count of good dies near the wafer perimeter.
• Tilted or bowed etch profiles at the edge as the sheath drops and field lines bend inward.
• Increased particle and defect adders as a worn or rough ring sheds material onto the wafer.
• Shorter mean time between qualifications and more frequent edge-recipe re-tuning, consuming engineering time and tool availability.
• Risk of arcing or accelerated wear on the ESC and adjacent hardware if the ring thins past its limit.

Common wear and failure modes

Erosion and height loss

The dominant failure mode is simple consumption. Continuous ion bombardment thins the ring and lowers its top surface relative to the wafer, which drops the sheath at the edge and progressively bends the etch profile inward. Once the ring height falls outside its qualified band, edge yield deteriorates even though the part is mechanically intact.

Surface roughening and particle generation

As the exposed face roughens with use, it becomes a source of flaking and redeposited material. Micro-masking on the roughened surface and the release of particles onto the wafer drive up adder defect counts, often appearing as an edge-localised defect signature on inspection.

Cracking, chipping and seating faults

Thermal cycling, mishandling during a PM or an imperfect seat on the chuck can produce cracks or chips, particularly at the thin inner edge. A poorly seated or damaged ring disturbs the local thermal and electrical boundary, can introduce arcing and risks dropping debris into the chamber.

Installation and replacement guidance

Replacement is a routine preventive-maintenance activity, but it must be performed cleanly to avoid introducing particles or seating errors. A typical sequence is:

• Vent the chamber and follow the tool’s lockout and cool-down procedure before opening, observing all RF and thermal safety steps.
• Remove the worn focus ring, then inspect the ESC top, edge seat and adjacent hardware for residue, damage or embedded particles.
• Clean the seating surfaces per the approved chamber-clean procedure and verify the area is free of flakes and debris.
• Handle the new ring only with clean, powder-free gloves or dedicated tooling, keeping it free of skin oils and contamination.
• Seat the ring squarely and concentrically against the wafer-edge datum, confirming it is flat, fully home and free of rocking.
• Close the chamber, pump down and perform leak-up and seasoning or conditioning runs as required by the recipe.
• Run qualification wafers and confirm edge uniformity, particle counts and CD before returning the tool to production.

Spare parts strategy for TEL etch consumables

Focus rings are high-frequency consumables, so supply reliability and cost-per-ring directly shape a fab’s etch operating budget and uptime. Sourcing ES7099-108 through ESCT Fab Support offers several advantages:

• A second-source, new part verified to the form, fit and function of the original TEL component.
• Competitive pricing on a frequently replaced consumable, reducing total cost of ownership across the etch fleet.
• A typical lead time of 4–5 weeks, supporting planned PM scheduling and buffer-stock management.
• Clear cross-referencing to OEM P/N 2L10-251409-11 and ESCT P/N ES7099-108 for confident ordering.
• Consistent part-to-part geometry that restores the qualified edge baseline at every changeout.

Frequently asked questions

What does this focus ring actually do?

It surrounds the wafer at the edge of the electrostatic chuck and extends the plasma sheath beyond the wafer perimeter, keeping ion trajectories vertical at the edge. This preserves etch uniformity and critical dimensions in the outermost dies while protecting the chuck and surrounding hardware from ion bombardment.

Is this an original OEM part?

No. This is a second-source, new part that is not an original Tokyo Electron component. It is manufactured and verified to match the form, fit and function of the original focus ring carrying OEM P/N 2L10-251409-11, and is offered as a cost-effective compatible alternative.

How often should the focus ring be replaced?

Replacement intervals depend on the recipe, RF power and run rate, so the cadence is set by each fab against its own edge-yield and particle data. Because the ring is sacrificial and erodes predictably, it is normally changed on a scheduled preventive-maintenance basis before its height falls outside the qualified window.

What happens if I run a worn ring too long?

As the ring thins, the sheath at the edge drops and etch profiles tilt inward, degrading edge CD and uniformity. A heavily worn ring also generates particles and, in extreme cases, exposes the chuck to bombardment or arcing, risking damage to far more expensive hardware.

What is the lead time and how do I order?

The typical lead time is 4–5 weeks. Orders can be placed against ESCT P/N ES7099-108, cross-referenced to OEM P/N 2L10-251409-11, which lets planners align deliveries with scheduled chamber PMs and maintain appropriate buffer stock.

Will it match my qualified process baseline?

The ring is produced to match the dimensional and material characteristics of the original part, so a fresh unit restores the edge geometry the process was qualified against. As with any consumable changeout, run your standard qualification wafers after installation to confirm edge uniformity and particle performance before returning the tool to production.

Summary

The Focus Ring 360-T4 (320) HS (OEM P/N 2L10-251409-11, ESCT P/N ES7099-108) is a sacrificial edge consumable for TEL 300 mm plasma etch chambers that shapes the plasma sheath at the wafer perimeter to protect edge uniformity, critical dimensions and particle performance. As one of the most frequently replaced parts in the chamber kit, it benefits from a reliable, cost-effective and dimensionally consistent supply. ESCT Fab Support offers this ring as a new, second-source component on a 4–5 week lead time, helping fabs hold edge yield while controlling consumable spend across their TEL etch fleet.

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 2L10-251409-11. 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.

Related parts

• 2L10-251409-11 FOCUS RING(LAB), 360-T4(320)HS
• 2L10-251708-11 RING, FOCUS LAB 360-320-5
• 2L10-251538-11 FOCUS RING, LAB 360-06-4.5 PL
• 2L10-251728-11 RING, FOCUS LAB 360-320-5-400H
• 2L10-251717-11 RING, FOCUS LAB 360-5T SA
• 2L10-251514-11 FOCUS RING, LAB 360-T4.5-306
• 2L10-251497-11 RING, FOCUS LAB 360-06-4
• 2L10-251061-21 FOCUS RING(LAB), 360-T4(320)