PEEK Applications | Analysis of PEEK Materials in CMP Retaining Rings and Key Technologies

In semiconductor manufacturing, the CMP (Chemical Mechanical Polishing) process is critical.

As a key consumable in this process, the CMP retaining ring fixes and supports the wafer. With increasing process complexity, requirements for retaining ring materials have become more stringent.

Polyetheretherketone (PEEK) is emerging as the ideal material for high-end CMP retaining rings due to its excellent heat resistance, chemical inertness, high mechanical strength, and ultra-low contamination characteristics. This article analyzes the technical points of CMP retaining rings and focuses on the advanced applications of PEEK.

*The listed PEEK applications represent common use cases. Actual applications of ZYPEEK are subject to official disclosures.

CMP (Chemical Mechanical Polishing, also called Chemical Mechanical Planarization) is a key process combining chemical etching and mechanical polishing. It removes excess or irregular dielectric layers on the wafer surface to achieve ultra-high precision planarization.

*The listed PEEK applications represent common use cases. Actual applications of ZYPEEK are subject to official disclosures.

CMP is widely used in semiconductor manufacturing to remove various surface materials (e.g., silicon oxide, tungsten, copper...).

Key consumables used in CMP include slurry, polishing pad, pad conditioner, CMP retaining ring, and membrane.

A CMP retaining ring is an annular component mounted on the polishing head assembly, serving three core functions:

The CMP process imposes stringent operating conditions on retaining rings, presenting three main challenges:

A wafer undergoes multiple CMP cycles with varying target materials. 

CMP is widely used in silicon wafer fabrication and semiconductor/IC manufacturing. With advanced packaging technologies, CMP is also applied in some back-end processes.

As process nodes shrink, traditional materials can no longer meet high-end CMP requirements. PEEK, with its superior comprehensive properties, has become the material of choice for next‑generation retaining rings. Key advantages include:

In certain high-pressure, high-temperature, and high-wear CMP processes, PEEK retaining rings can last several times longer than conventional materials.

*The listed PEEK applications represent common use cases. Actual applications of ZYPEEK are subject to official disclosures.

Currently, CMP retaining rings are mainly available in two structural designs:

High-performance plastic inserts are adhesively bonded to a metal base ring. Mature process and flexible fabrication, but risk metal exposure and adhesive contamination.

High-performance plastic is injection-molded to fully encapsulate the metal ring. No exposed metal or adhesive interface contamination, ideal for ultra-clean processes. Gaining rapid customer validation and adoption.

Both designs are widely used and can be manufactured with PEEK. As demands for cleanliness and consistency rise, overmolded retaining rings show strong growth potential.

High-quality raw materials are essential for CMP retaining rings, requiring ultra-high polymer purity, stability, and processability.

ZYPEEK 770G virgin PEEK resin pellets are field-proven and deliver excellent performance in CMP retaining ring applications.

*The listed PEEK applications represent common use cases. Actual applications of ZYPEEK are subject to official disclosures.

It features excellent melt stability for consistent long-term processing, ideal for precision injection molding of complex components. Key benefits:

//Ultra-high purity, minimizing black spots and impurities

//Exceptional toughness and impact resistance for high-pressure friction

//Excellent dimensional stability and standard flowability for superior processability

//Outstanding electrical, chemical, and flame-retardant properties, supporting diverse process requirements

//Custom formulations and modifications available to address specific application challenges

With R&D and manufacturing bases in Changchun, Shanghai, and Shenzhen, Joinature provides competitive high-performance material solutions for China’s semiconductor industry, helping customers "reduce costs, improve efficiency, and boost performance".

As semiconductor processes continue to advance, CMP retaining rings face higher material and structural requirements as a critical process control component. Leveraging its position as a leading high-performance engineering plastic, PEEK is rapidly becoming the preferred material for high-end CMP consumables.