OEM P/N:
ESCT P/N:
PART TYPE:
OEM:
The TEL Focus Ring PM4.0-380 is an annular plasma-confinement consumable that sits directly around the perimeter of the 300 mm wafer inside a Tokyo Electron (TEL) plasma etch process module. Carried under OEM part number 3D10-200997-11 and supplied by ESCT Fab Support as ES7099-024, it is one of the most influential single components in determining how a wafer etches across its outermost millimetres. The “PM4.0” descriptor associates the ring with a specific process-module hardware revision, while the “380” element relates to its dimensional family, so the part nests correctly against the electrostatic chuck, cathode and surrounding edge hardware.
A focus ring is positioned coplanar with, or slightly proud of, the wafer surface. Its job is to extend the plasma sheath beyond the silicon edge so that ions arrive at the wafer’s outer ring at the same angle and energy as they do at its centre. Without this ring, the sheath would curve sharply at the wafer edge, tilting ion trajectories, distorting feature profiles and rendering the outer few millimetres of every wafer unusable. In a 300 mm process where edge die represent a meaningful fraction of total device count, the focus ring is therefore a direct lever on yield.
Because it is sacrificial and sits in the most aggressive region of the plasma, the focus ring erodes over time and is replaced on a defined preventive-maintenance cadence. A dimensionally accurate, material-correct replacement keeps etch results repeatable from one ring change to the next, and from one chamber to the next within a matched fleet.
Within a TEL 300 mm plasma etch chamber, the focus ring performs several interlinked electrical, electrostatic and process functions that collectively govern edge behaviour:
Focus rings for TEL etch chambers are manufactured from carefully selected plasma-resistant materials whose composition is matched to the chemistry and energy of the process they serve. The choice of material directly affects erosion rate, particle behaviour and electrical coupling.
Depending on the process step the ring serves, focus rings of this type are typically produced from high-purity silicon, silicon carbide or quartz. These materials are chosen for low sputter yield, chemical compatibility with fluorine- and chlorine-based etch chemistries, and the ability to erode in a slow, predictable manner rather than spalling or generating particles. High purity also minimises metallic contamination that could diffuse into edge die.
Beyond raw material, the ring’s geometry is critical. Inner and outer diameters, step profile, thickness and flatness must reproduce the OEM specification so that the ring’s height relative to the wafer, and its dielectric/coupling characteristics, match the chamber’s tuned recipe. A ring that is even slightly out of tolerance shifts edge etch rate and profile tilt.
Because the focus ring controls the wafer’s outermost process zone, its condition feeds directly into the metrics fabs care about most:
As a frontline sacrificial part, the focus ring degrades through several recognisable mechanisms that drive its scheduled replacement.
Continuous ion bombardment gradually thins the ring and lowers its top surface. As the ring loses height relative to the wafer, the sheath at the edge collapses inward, tilting ions and pushing edge etch rate and profile out of specification. This slow drift is the primary reason a ring is replaced even before any catastrophic damage occurs.
Thermal cycling, mechanical stress during handling, and arcing can crack or chip the ring, particularly once it has thinned. Fractured material liberates particles that land on the wafer and chamber interior, driving defect counts up and forcing unscheduled wet-clean and replacement events.
Prolonged exposure roughens the ring surface and allows reaction by-products and polymer to accumulate. This changes the local gas chemistry, electrical coupling and erosion pattern at the wafer edge, gradually degrading uniformity and shortening the window in which the chamber holds its tuned baseline.
Focus ring replacement should be carried out by qualified personnel following TEL’s documented maintenance procedure for the specific process module. The sequence below summarises good practice and is not a substitute for the OEM service manual:
Focus rings are recurring consumables, so a dependable supply chain is as important as the part itself. ESCT Fab Support offers ES7099-024 as a cost-effective, fit-for-purpose alternative to single-sourcing through the OEM:
It surrounds the 300 mm wafer and extends the plasma sheath beyond the wafer edge, keeping ions arriving perpendicular to the surface so that the outermost die etch with the same profile and rate as the wafer centre. It also acts as a sacrificial shield that protects the chuck and edge hardware.
No. ES7099-024 is a second-source, new part supplied as an OEM-compatible equivalent to TEL P/N 3D10-200997-11. It is not an original Tokyo Electron part, but it is verified to match the original in form, fit and function.
Replacement intervals depend on the etch chemistry, RF power and wafer throughput, so they are set by each fab’s preventive-maintenance plan rather than a fixed figure. The ring is typically changed once erosion and height loss begin to affect edge uniformity, profile or particle metrics.
Focus rings of this type are made from plasma-resistant materials such as high-purity silicon, silicon carbide or quartz, selected for low sputter yield, chemical compatibility and minimal contamination. ESCT supplies the ring in the material grade appropriate to the original specification.
Because the part is built to the original dimensional and material specification, it is intended to restore the chamber to its established baseline. As with any consumable change, standard practice is to run conditioning and qualification wafers and confirm edge uniformity and particle performance before returning the tool to production.
The current lead time is 4-5 weeks. We recommend factoring this into maintenance planning and holding appropriate buffer stock so that a worn ring never delays a scheduled chamber clean.
The TEL Focus Ring PM4.0-380 (OEM P/N 3D10-200997-11, ESCT P/N ES7099-024) is a sacrificial plasma-confinement consumable that governs sheath shape, ion trajectory and edge etch uniformity at the perimeter of a 300 mm wafer in Tokyo Electron etch chambers. Built from plasma-resistant material to the original dimensional and electrical specification, it protects the chuck, supports edge die yield and keeps chambers matched across a fleet. Supplied by ESCT Fab Support as a second-source new part with a 4-5 week lead time, it offers a cost-effective, dependable route to maintaining repeatable etch performance through every preventive-maintenance ring change.
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 3D10-200997-11. 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.
Fill out the form below to request a quote for the part/s you require, making sure to include the OEM part number.
If the part you are looking for is not listed, get in touch and we will try to source it for you through our wide network of partners and suppliers.
We use cookies We use analytics cookies to see how visitors use this site, so we can improve it. They are set only if you accept. Read our Cookie Policy.
