OEM P/N:
ESCT P/N:
PART TYPE:
OEM:
The Graphite Cooled Tube Shield (AMAT OEM P/N 0020-86842) is a precision-machined, high-purity graphite component used within the indirectly heated cathode (IHC) source region of Applied Materials ion implanters. As its name indicates, it is a sacrificial shield that surrounds and protects a water- or gas-cooled tube assembly that routes coolant and electrical services into the hot, plasma-facing zone of the source. By interposing a solid graphite barrier between the energetic source environment and the cooled tube it surrounds, this shield keeps coolant integrity intact while taking the brunt of ion bombardment, thermal radiation and reactive species itself.
In an IHC source, a heated filament drives thermionic emission from a cathode, which in turn sustains an arc discharge that ionises the process feed gas. The temperatures, plasma densities and chemical aggressiveness inside this volume are extreme. Any cooled service line passing near the arc chamber must be defended, because a coolant breach or a short to the cooled tube would be catastrophic for the source. The cooled tube shield is the component engineered to absorb that abuse, confining erosion, deposition and sputtering damage to an inexpensive, routinely replaced graphite part rather than to the underlying cooled hardware.
Because it sits so close to the discharge, the shield is treated as a scheduled consumable. Fabs that run high-current or reactive-species recipes plan its replacement into their preventive maintenance cycle alongside filaments, cathodes, repellers and arc-chamber liners. Keeping a qualified shield on the shelf, with ESCT P/N ES227-0220, removes a single-point dependency that can otherwise hold a source rebuild hostage.
Within the IHC source assembly, the graphite cooled tube shield performs several interlocking duties that together protect the cooled service line and stabilise source behaviour:
The shield is manufactured from fine-grain, high-purity graphite selected for its behaviour under intense ion and thermal loading. Graphite is the material of choice in IHC source hardware because it tolerates very high temperatures without melting, sublimating cleanly rather than producing low-melting-point contaminants, and because it sputters predictably without introducing metallic species that would compromise implant purity.
IHC sources are frequently run with aggressive feed gases and dopant chemistries, and the shield must withstand the resulting chemical attack as well as physical sputtering in a high-vacuum environment. Dimensional accuracy and surface finish are therefore critical, because the part has to seat correctly against neighbouring source hardware and the cooled tube while holding a stable boundary throughout its service life.
A worn, cracked or incorrectly fitted cooled tube shield does not just shorten its own life, it can degrade source stability, beam quality and ultimately wafer yield. Because the shield protects a coolant-carrying line near the arc, its condition has consequences well beyond the part itself:
The dominant wear mechanism is steady sputter erosion. Energetic ions and neutrals continuously remove graphite from the plasma-facing surfaces, thinning the shield over its service life. Once thinning approaches the point where the cooled tube would be exposed, the part has reached end of life and must be replaced, regardless of how it appears elsewhere.
Repeated heating and cooling between source-on and source-off states imposes thermal cycling stress on the graphite. Over many cycles this can initiate cracks or cause surface spalling, both of which compromise the shield’s mechanical integrity and shed particulate into the source cavity.
Sputtered and condensed material from the source chemistry can build up on and around the shield. Heavy deposits change the local geometry, can bridge gaps to create unintended conductive paths, and may flake away later as contaminating debris, all of which argue for replacement on a disciplined schedule rather than running the part to visible failure.
The cooled tube shield is replaced as part of a routine IHC source rebuild. Work should be carried out by trained personnel following the relevant Applied Materials maintenance procedures and your fab’s safety protocols. The sequence below is a general guide only:
Source consumables like the cooled tube shield are predictable wear items, which makes them ideal candidates for a proactive spares programme. Stocking ES227-0220 ahead of need protects implanter uptime and removes procurement lead time from the critical path of a source rebuild. ESCT supports fabs with:
It shrouds a cooled tube, a coolant-carrying service line that runs near the arc region of the IHC source. The graphite shield absorbs ion sputtering and radiant heat that would otherwise attack that cooled hardware, protecting against erosion, shorting and coolant breaches.
No. ES227-0220 is supplied as a new, OEM-compatible part that cross-references to AMAT OEM P/N 0020-86842 and is verified to match the original in form, fit and function. It is not an original Applied Materials branded component and is not sold as such.
Graphite withstands the extreme temperatures of the source without melting, sputters cleanly without introducing metallic contamination into the ion beam, and tolerates reactive dopant chemistries. These properties make high-purity graphite the standard material for plasma-facing IHC source hardware.
Replacement intervals depend on beam current, feed-gas chemistry and duty cycle, so they vary by fab and recipe. The shield is generally changed as part of a scheduled source rebuild, alongside filaments, cathodes and other arc-chamber consumables, before erosion exposes the cooled tube.
Continuing to run an eroded shield risks exposing and damaging the cooled tube, which can lead to a coolant leak and an unplanned source shutdown. It also raises the likelihood of arcing, particulate generation and beam instability that hurt dose uniformity and yield.
Handle it only with clean, powder-free gloves and keep it in its protective packaging until fitting. Graphite is brittle and contamination-sensitive, so avoid impacts, skin contact and exposure to oils that could outgas or contaminate the source during operation.
The Graphite Cooled Tube Shield (AMAT OEM P/N 0020-86842, ESCT P/N ES227-0220) is a high-purity graphite consumable that protects the cooled service tube within the indirectly heated cathode source of AMAT ion implanters. By absorbing sputter erosion, radiant heat and chemical attack, it safeguards coolant integrity, helps stabilise the discharge and confines wear to a low-cost, scheduled-replacement part. Stocking a verified shield supports disciplined preventive maintenance, protects implanter uptime and helps maintain consistent beam quality and wafer yield.
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 Applied Materials part number 0020-86842. It is not an original OEM part and is not sold as one. It is not manufactured by, endorsed by, or affiliated with Applied Materials, 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.
