Applied Materials 0020-26822 Shield, 8" HTHU Depo Low Knee

Product Description

The 0020-26822 is an 8-inch HTHU Depo Low Knee shield assembly manufactured by Applied Materials for 200mm PVD thin-film deposition vacuum chambers. This annular shield component is fabricated from plasma-resistant high-purity metal alloy, precision machined with tailored contour profile (low knee geometry). It is installed inside the sputtering chamber surrounding the wafer pedestal, designed to intercept plasma sputtering by-products and protect chamber body surfaces from heavy film buildup. It features low particle emission and vacuum-compatible surface treatment for 200mm wafer metallization production environments. Available stock includes cleaned used and refurbished shields for wafer fab preventive maintenance and chamber rebuild projects.

Product Functions

• Block sputtered material by-products from depositing on chamber wall and non-target hardware surfaces inside PVD vacuum chamber.
• Define plasma confinement boundary and tune local electric field distribution to stabilize electron density during magnetron sputtering recipes.
• Low knee contour optimizes film edge profile on 200mm wafers and reduces edge overburden for metal and barrier deposition processes.
• Protect chamber base hardware from plasma bombardment and corrosive sputtering by-products, extending chamber service lifetime.
• Modular mechanical mounting design enables accurate positioning and alignment inside the AMAT PVD chamber.
• Collect most deposition residues on shield surface instead of critical chamber components, simplifying regular wet cleaning maintenance.
• Maintain consistent process geometry over production runs to preserve repeatable deposition rate and film uniformity.

Application Scenarios

• 200mm (8-inch) PVD magnetron sputtering chambers on Applied Materials Endura / Centura HTHU deposition platforms.
• Aluminum, copper and barrier metal thin-film sputtering processes for 8-inch semiconductor wafer metallization.
• Spare replacement for heavily coated, eroded or deformed 0020-26822 shields in production wafer fabrication tools.
• Chamber preventive maintenance, wet clean, target kit exchange and chamber rebuild projects for 200mm PVD systems.
• Process recipe qualification and edge film uniformity tuning after shield replacement.
• Spare parts inventory for semiconductor equipment service vendors and 8-inch wafer manufacturing fabs.

Common Problems

• Heavy film buildup: accumulated sputtering deposits on shield surface alter plasma geometry and degrade wafer edge film uniformity.
• Surface erosion: long-term plasma bombardment creates rough surface, introducing particle flaking and wafer yield contamination risk.
• Mechanical deformation: thermal cycling causes warping, changing gap spacing between shield and wafer and disrupting plasma distribution.
• Particle generation: peeling coating or cracked residual deposits drop contaminants onto wafer surface during process cycles.
• Mounting alignment drift: worn mounting features or residual deposit buildup leading to tilted shield installation.
• Plasma arcing: sharp eroded surface spots trigger random arc events, damaging wafer and chamber hardware.
• Refurbished unit risk: residual erosion and surface residue; full wet clean, dimensional inspection and particle check required before production chamber installation.