2L10-252373-11
RING,FOCUS LAB 360-313.5-5

Focus ring 360-313.5-5 (OEM P/N 2L10-252373-11), edge confinement ring for TEL 300 mm plasma etch systems

ESCT P/N ES7099-158, Tokyo Electron (TEL) compatible focus ring for 300 mm etch process chambers

The Focus Ring 360-313.5-5 is a circular plasma-confinement consumable that surrounds the production wafer inside a Tokyo Electron (TEL) 300 mm plasma etch chamber. Carrying TEL OEM part number 2L10-252373-11 and supplied by ESCT Fab Support under part number ES7099-158, it sits immediately outboard of the wafer edge on the electrostatic chuck assembly, forming a concentric annulus that extends the wafer surface into the surrounding hardware. Its job is to make the edge of the wafer behave, electrically and chemically, as though it were part of a much larger continuous surface, so that the last few millimetres of usable silicon etch with the same fidelity as the centre.

The numerals in the part name describe its geometry rather than a model code. A nominal 360 mm outer envelope, an inner aperture sized close to the 300 mm wafer diameter and a defined ring height combine to set the position of the plasma sheath relative to the wafer perimeter. In a process where the sheath must remain flat and vertical right out to the wafer edge, those millimetres of ring dimension translate directly into edge etch rate, feature tilt and critical-dimension (CD) control across the outermost dies.

Because the focus ring is consumed by the very plasma it is there to shape, it is one of the most frequently replaced parts in any high-volume etch operation. It is a planned, scheduled consumable, and the availability and consistency of a quality-verified replacement directly affect chamber uptime, wafer-to-wafer repeatability and the cost of ownership of the tool.

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

Within a TEL capacitively or inductively coupled etch chamber, the focus ring performs several overlapping electrical and physical roles that together govern how the wafer edge is processed:

• Extends the plasma sheath beyond the physical wafer edge so the sheath boundary stays parallel to the wafer rather than curving down into the chuck, keeping ion trajectories vertical at the perimeter.
• Confines the active plasma over the wafer area, helping to define the radial boundary of the discharge and reduce edge-region plasma leakage.
• Provides a controlled RF and electrical environment around the wafer edge so that field uniformity, and therefore etch rate, is maintained out to the last die.
• Acts as a sacrificial surface that takes the ion bombardment and polymer deposition that would otherwise attack the chuck edge and surrounding hardware.
• Sets the mechanical datum for wafer edge position, giving repeatable concentric placement of the wafer relative to the chamber and the gas flow field.
• Influences local gas conductance and by-product evacuation at the wafer perimeter, contributing to uniform chemistry across the edge exclusion zone.

Material and process performance

Plasma and chemical resistance

Focus rings of this type are produced from carefully selected high-purity materials such as single-crystal or polycrystalline silicon, silicon carbide or, in some recipes, high-purity quartz, chosen to match the dominant chemistry of the process. The material must erode in a predictable, controllable way under fluorine- or chlorine-based plasmas without releasing metallic contamination or generating particles. ESCT-supplied rings are sourced to high-purity specifications so that erosion behaviour, resistivity and trace-metal content track the original equipment specification.

• High-purity base material to minimise mobile-ion and metallic contamination of the wafer edge.
• Controlled electrical resistivity so the ring presents the correct RF coupling and sheath profile.
• Predictable erosion rate that allows a defined wafer-count service interval to be set.
• Resistance to chemical attack and polymer build-up across the chamber’s operating chemistries.

Dimensional and surface precision

The 360-313.5-5 dimensions are held to tight tolerances because the ring height and inner-diameter step define the sheath geometry at the wafer edge. Flatness, parallelism and surface finish all influence thermal contact with the chuck and the electrical interface to the wafer. A ring machined or moulded outside tolerance shifts the sheath and degrades edge uniformity even when the bulk material is correct.

• Tight control of outer diameter, inner aperture and ring height to set sheath position.
• Flat, parallel seating surfaces for consistent thermal and RF contact with the chuck.
• Defined surface finish to limit particle shedding and polymer adhesion.
• Concentric geometry to maintain repeatable wafer-to-ring spacing on every cycle.

Impact on tool performance and yield

Few consumables have as direct an effect on edge yield as the focus ring. As it erodes, the sheath it supports gradually changes shape, and the etch behaviour of the outermost dies drifts accordingly. Using a ring that is in-specification and consistent from lot to lot keeps that drift slow and predictable:

• Tighter edge-to-centre etch-rate uniformity and improved CD control at the wafer perimeter.
• More usable dies inside the edge exclusion zone, directly improving wafer yield.
• Reduced feature tilt and profile distortion at the outer radius caused by a bent sheath.
• Lower particle counts and reduced metallic contamination when the ring material is to specification.
• Predictable end-of-life behaviour, allowing replacement to be scheduled rather than reactive.
• Stable wafer-to-wafer and chamber-to-chamber matching across the fleet.

Common wear and failure modes

Erosion and height loss

The dominant wear mechanism is steady erosion of the upper surface by ion bombardment. As the ring loses height, the plasma sheath drops relative to the wafer edge, ion trajectories begin to tilt and edge etch rate and profile shift. Beyond a defined height-loss threshold the edge dies fall out of specification and the ring must be replaced even though it is still physically intact.

Cracking and thermal fatigue

Repeated thermal cycling, mishandling during installation or localised hot spots can crack brittle silicon, silicon carbide or quartz rings. A cracked ring is an immediate particle source and can shed fragments onto the wafer or chuck. Any visible chip, hairline crack or flaking surface is grounds for immediate removal from service.

Polymer build-up and contamination

Process by-products and polymer films accumulate on the ring surface over time. Excessive or flaking deposits change the local electrical and gas environment, can re-deposit as defects and signal that the part has reached the end of its useful interval. Contamination from a degraded or off-specification ring also raises trace-metal and particle levels at the wafer edge.

Installation and replacement guidance

The focus ring is replaced during scheduled preventive maintenance on the etch chamber. Because it is a high-purity, brittle consumable, cleanliness and handling discipline matter as much as mechanical fit. Follow the tool owner’s documented procedure; the steps below summarise good practice:

• Vent the chamber and isolate it following the approved lock-out and safety procedure before opening.
• Remove the worn ring carefully, noting its orientation, and inspect the chuck edge and seating surfaces for residue, damage or erosion.
• Clean the seating area to the specified standard so the new ring beds flat with good thermal and RF contact.
• Unpack the replacement ES7099-158 in a clean environment using clean-room gloves; handle by the edges and avoid contact with the active surfaces.
• Seat the ring concentrically in its correct orientation, confirming it lies flat with no rock, gap or particle trapped beneath it.
• Close the chamber, pump down, leak-check and run the prescribed season or conditioning recipe before production wafers.
• Reset the consumable wafer counter and verify edge uniformity with a qualification wafer before releasing the chamber.

Spare parts strategy for TEL etch consumables

Focus rings are consumed on a known cadence, which makes them ideal candidates for a managed spares programme. ESCT Fab Support helps fabs keep TEL 300 mm etch chambers running without overpaying or over-stocking:

• Second-source, brand-new rings verified to the form, fit and function of TEL OEM P/N 2L10-252373-11.
• High-purity material sourcing to keep erosion behaviour and contamination performance consistent.
• Competitive pricing against OEM list, reducing the cost of ownership of a frequently replaced consumable.
• A typical lead time of 4-5 weeks, supporting forward scheduling against your maintenance calendar.
• Clear cross-referencing under ESCT P/N ES7099-158 for straightforward reordering and stock control.
• Support for volume agreements and buffer stock to protect chamber uptime across a fleet.

Frequently asked questions

What does this focus ring actually do in the chamber?

It surrounds the wafer on the chuck and extends the plasma sheath beyond the wafer edge, keeping ion trajectories vertical and the etch uniform right out to the outermost dies. It also confines the plasma and protects the chuck edge as a sacrificial surface.

Is this an original TEL OEM part?

No. This is a brand-new, second-source replacement part. It is supplied as a new OEM-compatible component verified to match the form, fit and function of TEL OEM P/N 2L10-252373-11, but it is not an original OEM-branded part and is not sold as one.

How often does a focus ring need replacing?

Service life depends on the process chemistry, power and wafer throughput, so it is set by accumulated wafer count or measured height loss rather than a fixed calendar period. Most fabs define a replacement interval from edge-uniformity data and erosion measurements for each specific recipe.

What material is the ring made from?

Focus rings of this type are made from high-purity materials such as silicon, silicon carbide or quartz, selected to match the chamber chemistry and to erode cleanly without contaminating the wafer. ESCT sources the part to high-purity specifications consistent with the original equipment requirement.

How do I know when this part has failed or worn out?

The usual indicators are drift in edge etch rate or critical dimensions, rising particle counts, and measurable height loss past the defined limit. Any visible crack, chip or flaking surface is cause for immediate replacement, as it becomes a particle source.

What is the lead time and how do I reorder?

The typical lead time is 4-5 weeks. Reorder using ESCT P/N ES7099-158, which cross-references to TEL OEM P/N 2L10-252373-11, and contact ESCT Fab Support to arrange buffer stock or a scheduled-delivery agreement against your maintenance plan.

Summary

The Focus Ring 360-313.5-5 (ESCT P/N ES7099-158, TEL OEM P/N 2L10-252373-11) is a high-purity, sacrificial edge-confinement consumable for TEL 300 mm plasma etch chambers. By extending and shaping the plasma sheath at the wafer perimeter, it controls edge etch uniformity, critical dimensions and particle performance, and as it erodes it directly determines how many edge dies remain in specification. Supplied brand-new and second-source, verified to form, fit and function, it offers a cost-effective, consistent route to keeping TEL etch chambers in qualified production with predictable service intervals.

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 2L10-252373-11. 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

• 2L10-252373-11 RING, FOCUS LAB 360-313.5-5
• 2L10-252318-11 RING, FOCUS LAB 360-315-5
• 2L10-252644-11 RING, FOCUS 305-T5G50L LAB(FLT)
• 2L10-252645-11 RING, FOCUS 306-T6G50L LAB (FLT)
• 2L10-252646-11 RING, FOCUS 314-T5G50L LAB SHAL
• 2L10-252647-11 RING, FOCUS 318-T5.5G50L LAB
• 2L10-252691-11 RING, FOCUS 311-T5.5G50L LAB 2S
• 2L10-252692-11 RING, FOCUS 312-T6G50L LAB 2S