Rethinking CMP for advanced packaging
How flexible, data-driven and resource-efficient platforms can support chiplets, 3D integration and panel-level packaging.
By Accretech (Europe).
As the semiconductor industry enters an era defined less by traditional transistor scaling and more by heterogeneous integration, advanced packaging has become one of the most important innovation battlegrounds. Chiplets, 2.5D and 3D integration, fan-out architectures, and the emergence of panel-level packaging (PLP) are enabling new levels of performance, functionality, and cost efficiency. Yet these packaging innovations bring significant manufacturing challenges, particularly for one critical process: Chemical Mechanical Polishing (CMP).
For decades, CMP was regarded as a mature, highly predictable process used primarily to achieve the planar surfaces required in semiconductor fabrication. Today, however, the technology finds itself at the centre of a rapidly changing production landscape. New materials, diverse substrate sizes, increasingly complex package architectures, and mounting sustainability expectations are forcing equipment suppliers and semiconductor manufacturers to rethink what CMP systems must deliver.
The question facing the industry is no longer whether CMP can provide high-precision planarisation. Instead, it is whether modern CMP platforms can evolve quickly enough to support the demands of advanced packaging while simultaneously meeting increasingly stringent environmental and operational requirements. The answer lies in a new generation of flexible, digitally connected, and sustainability-focused CMP systems.
Advanced packaging changes the rules
The semiconductor industry’s long-standing reliance on Moore’s Law has gradually given way to a more diverse approach to performance enhancement. Rather than simply shrinking transistors, manufacturers are increasingly combining multiple specialised dies into sophisticated package-level systems.
Chiplet-based architectures illustrate this trend clearly. Instead of developing increasingly large monolithic chips, designers can integrate separate compute, memory, power management, RF, photonic, and acceleration functions into a single package. This approach delivers advantages in performance, yield, design flexibility, and cost.
However, such heterogeneous integration significantly increases manufacturing complexity. Surfaces must remain exceptionally flat to support reliable interconnections between disparate dies and substrates. Any topographic variation can negatively affect bonding quality, electrical performance, and long-term reliability.
CMP therefore becomes a process enabler rather than simply a polishing step. As packaging architectures become more sophisticated, the tolerance for process variation decreases dramatically.
At the same time, advanced packaging technologies are introducing a much broader range of substrates and geometries. Traditional production environments dominated by 300mm and 200mm silicon wafers are increasingly giving way to mixed-format manufacturing. Facilities may now process 150mm, 100mm, or even smaller research-oriented wafers alongside conventional production substrates. Panel-level packaging expands this diversity even further by replacing circular wafers with large rectangular or square panels that offer improved manufacturing economics and area utilisation.
Such variation creates significant challenges for conventional CMP tools that were originally designed around standardised wafer formats. Equipment flexibility is becoming as important as polishing performance itself.
Material diversity presents new challenges
Just as substrate formats are changing, the range of materials entering CMP workflows is also expanding dramatically.
Historically, CMP equipment was optimised primarily for silicon and silicon dioxide processing. Today’s advanced packaging applications involve a far wider material spectrum.
Wide-bandgap semiconductors such as silicon carbide (SiC) and gallium nitride (GaN) are increasingly important in power electronics and high-frequency applications. These materials possess mechanical characteristics very different from silicon, requiring specialised process conditions to achieve the desired removal rates and surface quality.
Meanwhile, advanced packaging introduces softer and often chemically sensitive materials, including polyimides, build-up dielectrics, packaging resins, and other polymer-based layers. These materials demand entirely different polishing strategies, pressure profiles, slurry chemistries, and endpoint control techniques.
For manufacturers, this creates a significant operational challenge. The ability to switch rapidly between vastly different material classes without extensive cleaning procedures, contamination risks, or lengthy requalification periods has become a major competitive advantage.
Modern CMP equipment must therefore provide both process flexibility and process stability. Achieving one without the other is no longer sufficient.
The rise of high-mix manufacturing
Another consequence of advanced packaging is the emergence of increasingly diverse production environments.
Unlike traditional high-volume semiconductor manufacturing, many advanced packaging initiatives involve shorter product lifecycles, smaller batch sizes, and accelerated development schedules.
Research institutes, specialist foundries, start-ups, and established semiconductor companies alike are pursuing rapid innovation cycles to capture emerging opportunities.
These environments require CMP platforms capable of supporting frequent recipe development and process experimentation. Engineers need the ability to evaluate new materials, optimise novel integration schemes, and quickly transition from proof-of-concept work to limited-volume production.
According to the white paper, flexibility in substrate handling, process switching, and throughput optimisation is rapidly becoming a baseline requirement rather than a premium capability.
The most successful CMP platforms of the future will be those that can accommodate this high-mix, high-variation manufacturing environment without sacrificing repeatability or yield.
Sustainability moves to centre stage
While advanced packaging is reshaping technical requirements, sustainability concerns are simultaneously transforming how fabs evaluate manufacturing processes.
CMP has long been recognised as one of the most resource-intensive steps in semiconductor production. Its combination of abrasive slurries, extensive rinsing operations, and demanding cleanliness requirements creates significant environmental impacts.
The white paper estimates that CMP can account for approximately 40% of total ultrapure water (UPW) consumption within semiconductor manufacturing operations.
Additionally, polishing a single 200mm wafer can generate between 30 and 50 litres of slurry waste containing abrasive particles and chemicals that are difficult to recycle.
Energy consumption is also substantial, with CMP processes contributing approximately 5-6% of overall fab electricity usage during operation.
Life-cycle assessment studies have highlighted several major contributors to CMP’s environmental footprint. The production and disposal of slurry chemicals, particularly formulations containing ingredients such as benzotriazole and hydrogen peroxide, represent significant environmental burdens. The energy needed for polishing, pad conditioning, and ultrapure water generation further increases process impacts.
As governments tighten environmental regulations and semiconductor companies pursue ambitious ESG targets, reducing these impacts has become a business priority.
The industry’s sustainability expectations are evolving rapidly. Throughput and yield remain critical metrics, but water consumption, energy efficiency, waste generation, and carbon emissions are increasingly influencing purchasing decisions and process development strategies.
Designing CMP for a more sustainable future
Meeting sustainability objectives does not simply require operational improvements. Instead, environmental performance is becoming an integral component of tool design.
One of the most significant developments involves wastewater management. New CMP systems increasingly incorporate on-tool waste stream separation technology, enabling fabs to segregate effluents according to chemical composition and contamination levels.
This approach simplifies downstream treatment and creates opportunities for partial water recycling. In some cases, rinse water generated during relatively clean oxide polishing processes may be suitable for recovery and reuse within fab water systems.
Slurry delivery technology is also improving. Modern injection systems distribute slurry more efficiently across wafer surfaces, increasing utilisation rates while reducing overall chemical consumption. Better distribution uniformity not only cuts waste but can also improve process consistency and reduce defect generation.
Pad conditioning systems are undergoing similar optimisation. Real-time monitoring allows tools to adjust conditioning pressure and frequency dynamically, extending pad lifetime while maintaining stable material removal rates. Reducing pad consumption delivers both operational and sustainability benefits.
Energy efficiency has emerged as another major development area. Advanced motor technologies, intelligent standby modes, and thermal recovery systems are helping reduce overall tool power requirements. Some equipment manufacturers have even expanded sustainability efforts beyond tool operation, incorporating renewable energy into manufacturing facilities and optimising logistics to minimise transportation-related emissions.
These initiatives reflect a broader industry shift: sustainability is increasingly being engineered into CMP platforms rather than treated as a separate compliance activity.
Flexibility through modular design
To address both technical and environmental challenges, equipment architecture is becoming increasingly modular.
The white paper highlights the importance of platforms capable of supporting multiple substrate formats without requiring entirely separate tool investments. Modern systems can often transition between 6-inch, 4-inch, and even 2-inch wafers within a single platform, with changeovers measured in hours rather than days.
Such flexibility delivers obvious financial advantages, reducing capital expenditure and increasing tool utilisation. However, the environmental benefits are equally important.
Avoiding duplicate equipment reduces manufacturing footprints and resource consumption. Faster transitions between process types minimise downtime and reduce the need for extensive cleaning cycles, conserving water and chemicals.
Modular process chamber designs represent another important innovation. By dedicating different chambers to specific material sets or process requirements, manufacturers can minimise cross-contamination risks while reducing cleaning frequency. This enables more efficient operation across diverse process flows.
Similarly, advancements in pad handling allow faster replacement and calibration while maintaining process consistency. Some systems now support programmable pad zones capable of polishing different substrates using tailored process recipes on the same platform. Together, these innovations significantly improve equipment adaptability while supporting sustainability objectives.
Digitalisation transforms process control
Perhaps the most transformative development in next-generation CMP is the integration of automation and digital intelligence.
Historically, many process adjustments relied heavily on operator experience and offline analysis. Today’s manufacturing environments increasingly demand real-time feedback, predictive control, and data-driven decision-making.
Advanced CMP platforms are therefore incorporating automated wafer handling, endpoint detection, and precision pressure control systems designed to eliminate variability and reduce operator intervention. Beyond the tool itself, integration with Manufacturing Execution Systems (MES) and Enterprise Resource Planning (ERP) platforms enables smarter production scheduling.
For example, grouping wafers with similar process requirements can minimise chamber transitions and reduce the number of rinse cycles required between runs. Such optimisation lowers water consumption, decreases downtime, and improves overall equipment effectiveness.
Predictive maintenance capabilities are becoming equally important. By continuously monitoring polishing rates, pad wear, vibration signatures, and other process parameters, CMP tools can identify emerging issues before they result in scrap or unplanned maintenance events.
This not only improves yield but also reduces wasted materials and energy associated with failed processing runs.
Digital traceability further strengthens sustainability efforts. Detailed logging of slurry use, energy consumption, water flow, and process conditions enables fabs to quantify environmental performance with increasing precision. Such capabilities support both regulatory compliance and internal ESG reporting requirements.
Looking towards AI-driven CMP
The evolution of CMP is unlikely to stop with today’s automation technologies.
Future systems are expected to leverage artificial intelligence, simulation-driven process development, and digital twin technologies to optimise performance and sustainability simultaneously. According to the white paper, AI-enabled control architectures and predictive diagnostics will become important tools for managing increasingly complex process environments.
Digital twins offer particularly compelling possibilities. By creating virtual representations of CMP processes, engineers can test process changes, evaluate new materials, and optimise recipes before committing actual wafers to production.
This approach can dramatically accelerate development cycles while minimising waste, a critical advantage for advanced packaging applications characterised by rapid innovation and limited production volumes.
As these capabilities mature, sustainability metrics may become as tightly controlled as traditional manufacturing KPIs. Rather than measuring environmental performance retrospectively, fabs could establish resource consumption targets per wafer pass, covering parameters such as litres of ultrapure water, grams of slurry, and kilowatt-hours of energy consumed. CMP tools would then be expected to meet those targets by design.
CMP as a strategic technology
The semiconductor industry’s packaging revolution is fundamentally changing perceptions of CMP. No longer viewed as a routine backend process, CMP is emerging as a strategic technology that enables the successful implementation of advanced integration schemes. Its ability to deliver precise planarisation across increasingly diverse materials and package structures directly influences product performance, manufacturability, and cost.
At the same time, the process sits at the intersection of two of the industry’s most important priorities: advanced packaging and sustainability.
The next generation of CMP platforms must therefore achieve a delicate balance. They must be flexible enough to support chiplets, heterogeneous integration, PLP, wide-bandgap materials, and future packaging innovations. Yet they must also minimise water use, reduce chemical waste, lower energy consumption, and provide the data transparency demanded by regulators and corporate sustainability programmes.
The emerging consensus is that these goals are not mutually exclusive. In fact, the most adaptable systems are often the most efficient. Platforms designed to switch rapidly between materials, automate process optimisation, and integrate environmental management capabilities can simultaneously improve productivity and sustainability.
As advanced packaging becomes increasingly central to semiconductor innovation, CMP’s role will only grow in importance. The tools that combine precision, flexibility, intelligence, and sustainability will help define the future of semiconductor manufacturing and determine how effectively the industry navigates its next major transition.
