3D10-250316-11
(C2)CEL,INNER(SH-OX1.75)

TEL inner silicon cathode electrode, (C2)CEL, INNER(SH-OX1.75) (OEM P/N 3D10-250316-11)

ESCT Fab Support 2nd Source NEW replacement cathode, ESCT P/N ES7099-012

The (C2)CEL, INNER(SH-OX1.75) is an inner silicon cathode electrode used in the upper-electrode assembly of Tokyo Electron (TEL) 300 mm capacitively coupled plasma (CCP) etch chambers. In TEL nomenclature, “CEL” identifies a silicon cathode/electrode consumable, and the “INNER” descriptor places this part at the centre of a segmented upper-electrode stack where it directly faces the wafer and the plasma. The “SH-OX1.75” designator relates to the surface treatment and dimensional class of the electrode body. As a plasma-facing consumable, it is one of the components that most directly governs etch behaviour and is consumed steadily over the life of a wet-clean or preventive-maintenance (PM) cycle.

This electrode is supplied by ESCT Fab Support under part number ES7099-012 as a 2nd Source NEW component, dimensionally and functionally engineered to match TEL OEM P/N 3D10-250316-11. It is intended as a like-for-like replacement for fabs seeking to control cost-of-ownership and secure supply continuity for high-volume etch tooling. Typical lead time is 4–5 weeks.

Because the inner cathode sits at the heart of the RF power-delivery path and the etch field, its material quality, surface finish and dimensional accuracy have an outsized effect on plasma uniformity, particle generation and overall process repeatability. The notes below describe what this part does, how it is built, how it wears, and how to manage it as a spare.

Functional role in the TEL upper-electrode assembly

In a TEL CCP etch chamber, the upper electrode is the powered or grounded surface that, together with the lower electrode (electrostatic chuck), establishes the plasma sheath above the wafer. The inner cathode electrode is the central segment of that upper assembly. It performs several interlinked functions that together define etch outcome:

• Couples RF energy into the chamber to sustain and shape the plasma over the central region of the 300 mm wafer.
• Provides a high-purity silicon surface that participates in the plasma chemistry, acting as a sacrificial source that helps scavenge fluorine and stabilise the etch environment.
• Defines the electrode gap and surface profile that influence sheath thickness, ion energy and centre-to-edge uniformity.
• Helps distribute process gas flow and electric field symmetrically across the wafer centre when integrated with the surrounding electrode segments.
• Contributes to thermal management of the plasma-facing surface, maintaining a stable surface temperature that keeps etch and deposition rates consistent.
• Acts as a controlled-wear consumable, allowing the chamber to maintain known performance until a scheduled replacement is due.

Material and process performance

High-purity silicon construction

The inner cathode is manufactured from high-purity silicon, the standard material for plasma-facing electrodes in fluorine- and fluorocarbon-based etch processes. Silicon is chosen because it erodes predictably and cleanly under ion bombardment, contributes silicon into the plasma rather than metallic or organic contaminants, and helps consume free fluorine that would otherwise attack other chamber surfaces. The purity grade and resistivity of the silicon are controlled because trace metallic impurities can transfer to the wafer and degrade device yield.

• High-purity silicon body selected for low metallic contamination and stable plasma interaction.
• Controlled resistivity for consistent RF coupling and predictable sheath behaviour.
• Sacrificial erosion characteristics that support fluorine scavenging and process stability.
• Mechanical tolerance held to match the OEM electrode so the assembly gap and fit are preserved.

Surface finish and dimensional control

The plasma-facing surface is finished to a defined specification because surface texture, flatness and edge geometry all affect how the electric field and ion flux distribute across the wafer. A surface that is too rough generates excess particulate as it erodes, while a poorly controlled profile shifts the plasma density and harms uniformity. ESCT controls the surface finish, flatness and overall dimensions of ES7099-012 so that the part seats correctly in the assembly and reproduces the field profile of the original electrode.

• Defined surface finish to minimise particle shedding and maintain stable erosion.
• Flatness and parallelism controlled to preserve electrode gap and field symmetry.
• Diameter, thickness and mounting features matched to the TEL OEM geometry.
• Clean handling and packaging to keep contamination off the plasma-facing surface before installation.

Impact on tool performance and yield

Because the inner cathode sits directly in the plasma over the centre of the wafer, any deviation in its condition shows up quickly in process metrics. A worn, contaminated or out-of-tolerance electrode is a common root cause behind drifting etch rate, uniformity excursions and rising particle counts. Maintaining this part to specification protects several yield-critical parameters:

• Centre-to-edge etch uniformity, which depends on a symmetric field and stable electrode surface.
• Etch-rate repeatability across wafers and lots, governed by consistent RF coupling.
• Particle and defectivity performance, which degrades as the electrode erodes unevenly or sheds material.
• Critical-dimension (CD) and profile control, sensitive to ion energy and sheath stability.
• Chamber-matching across a fleet of tools running the same recipe.
• Mean time between cleans, since a stable electrode reduces unscheduled interventions.

Common wear and failure modes

Erosion and thinning

The dominant wear mechanism is steady erosion of the silicon surface under continuous ion bombardment. As the electrode thins, the electrode gap opens, RF coupling shifts and the plasma sheath changes, which gradually moves etch rate and uniformity away from the qualified window. Erosion is expected and designed-for, but once the surface passes its usable thickness the part must be replaced to restore the original process baseline.

Surface pitting, cracking and localised damage

Non-uniform plasma loading, arcing or thermal cycling can cause localised pitting, micro-cracking or chipping of the silicon. These defects concentrate the field, accelerate local erosion and become a source of particles that land on the wafer. Cracks also risk catastrophic fracture of a brittle silicon component, so any electrode showing visible cracking or edge damage at a PM should be retired rather than reused.

Contamination and polymer build-up

Fluorocarbon and by-product deposits accumulate on the electrode surface during processing, and metallic or particulate contamination can transfer from handling or from upstream chamber wear. Build-up changes the effective surface chemistry and electrical behaviour, degrades uniformity and raises defectivity. When deposits can no longer be removed by the standard clean, or when contamination is suspected, replacement with a new electrode is the reliable path back to a clean baseline.

Installation and replacement guidance

Silicon electrodes are brittle and contamination-sensitive, so they should be handled only by trained maintenance technicians following the TEL chamber maintenance procedure for the specific platform. The following steps summarise good practice; always defer to the OEM service documentation and your fab’s PM specification:

• Power down, isolate RF and gas supplies, and vent the chamber following the tool’s lockout/tagout and safety procedure.
• Open the upper-electrode assembly and remove the old inner cathode, noting its orientation and the condition of mating surfaces.
• Inspect the surrounding electrode segments, bonding interface and gas-distribution features for wear or damage before fitting the new part.
• Unpack ES7099-012 in a clean area and handle with powder-free gloves; avoid touching the plasma-facing surface and inspect for shipping damage.
• Seat the new electrode in the correct orientation, confirming flush, even contact and the specified electrode gap.
• Reassemble per the TEL torque and sequence specification, then verify chamber integrity with a leak/pressure check.
• Run season/conditioning and qualification recipes, then confirm etch rate, uniformity and particle performance before returning the tool to production.

Spare parts strategy for TEL etch consumables

The inner cathode is a recurring consumable, so it belongs in a planned spares programme rather than being ordered reactively after an unplanned excursion. With a 4–5 week lead time on ES7099-012, holding buffer stock keyed to your PM frequency prevents tool downtime and protects production schedules. A sensible strategy includes:

• Forecasting consumption from RF hours or wafer counts between electrode replacements.
• Holding safety stock sized to lead time so a PM is never delayed waiting on parts.
• Qualifying the 2nd source part on a representative tool before fleet-wide adoption.
• Tracking lot and installation data to correlate electrode condition with process drift.
• Storing electrodes in clean, dry, original packaging to protect the silicon surface until use.

Frequently asked questions

What does the (C2)CEL, INNER(SH-OX1.75) electrode actually do?

It is the central silicon cathode segment of the upper-electrode assembly in a TEL 300 mm plasma etch chamber. It couples RF energy into the plasma over the centre of the wafer, helps shape sheath and field uniformity, and acts as a sacrificial silicon surface that supports stable etch chemistry. It is a consumable replaced on a maintenance interval.

Is this an original TEL OEM part?

No. ES7099-012 is a 2nd Source NEW component supplied by ESCT Fab Support. It is not an original Tokyo Electron part and is not sold as one. It is manufactured as a NEW, OEM-compatible replacement engineered to match the form, fit and function of TEL OEM P/N 3D10-250316-11. TEL and its part numbers are referenced only to identify compatibility.

What material is the electrode made from?

It is made from high-purity silicon, the standard material for plasma-facing etch electrodes. Purity has to be high to limit metallic contamination transfer to the wafer and to ensure the silicon erodes predictably while helping to stabilise fluorine-based plasma chemistry.

How do I know when the inner cathode needs replacing?

Replacement is normally driven by accumulated RF hours or wafer count defined in your PM plan, supported by visual inspection. Indicators include the electrode reaching its usable thickness from erosion, visible pitting or cracking, deposits that cannot be cleaned, or process signals such as etch-rate drift, uniformity excursions or rising particle counts.

Why does the inner electrode matter so much for yield?

Because it sits directly in the plasma over the wafer centre, its surface condition and dimensions strongly influence field symmetry, ion energy and particle generation. Small deviations translate quickly into uniformity, CD and defectivity changes, making it one of the more yield-sensitive consumables in the chamber.

What is the lead time for ES7099-012?

Typical lead time is 4–5 weeks. Because the part is a recurring consumable, we recommend forecasting demand from your PM interval and holding buffer stock sized to this lead time to avoid tool downtime.

Summary

The (C2)CEL, INNER(SH-OX1.75) inner silicon cathode electrode (TEL OEM P/N 3D10-250316-11) is a plasma-facing consumable at the centre of the upper-electrode assembly in TEL 300 mm CCP etch chambers, where it governs RF coupling, plasma uniformity and particle performance. Manufactured from controlled high-purity silicon with a defined surface finish and dimensional fit, ESCT Fab Support’s 2nd Source NEW equivalent, ES7099-012, is built to reproduce the form, fit and function of the original while supporting a cost-effective, secure spares strategy with a 4–5 week lead time.

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 3D10-250316-11. 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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