150mm fab closures pose structural industry risk

The phase-out of 150mm CMOS is not just a product change; it is a structural industry risk that is causing significant disruptions in the semiconductor market, according to Dr. Ulrich Bretthauer at X-Fab. Manufacturers across various sectors such as automotive, industrial, medical, and aerospace heavily rely on integrated circuits for their electronic products and systems. The recent discontinuation of 150mm (6-inch) wafer-based CMOS processes by some foundries has created challenges for companies, disrupting supply chains and forcing design engineers to reevaluate their strategies.

The end of CMOS chip production on 150mm wafers has particularly impacted mature nodes at 0.6µm and larger, commonly used for analog and mixed-signal ICs like sensor interfaces and power management chips. The sudden announcement of the end-of-life for 150mm CMOS processes caught many design teams off guard, leading to urgent meetings to assess stockpiles, initiate redesigns, and validate existing systems. This unexpected development has pushed companies to quickly adapt to the changing landscape of semiconductor manufacturing.

As wafer sizes have increased from 150mm to 200mm and 300mm, the industry has witnessed a shift towards larger wafers to meet the growing demand for chips while reducing costs. While 300mm wafers have become standard for advanced nodes, many analog and mixed-signal applications have remained on 150mm wafers using mature nodes like 0.6µm. However, the declining production volumes of 150mm wafers have made it challenging to sustain CMOS processes on these smaller wafers, leading to their discontinuation by several foundries.

With the discontinuation of 150mm wafer production, companies are facing pressure to quickly assess customer demand, secure last-time buys, and plan for replacements within tight timelines set by industry standards. Migration of affected integrated circuits to new process nodes has become a necessity, requiring a careful balance of technical considerations and business strategies, especially for custom ASIC development. Selecting the right foundry partner with a proven track record and reliable supply chain management is crucial in this transition.

Instead of immediately transitioning to sub-130nm processes on 300mm wafers, many manufacturers are exploring intermediate solutions like 350nm or 180nm nodes on 200mm wafers. These nodes offer a balance between efficiency, design simplicity, and long-term viability, with lower development costs compared to advanced nodes. The maturity of the 350nm node enables faster time to market and high first-time-right success rates, making it an attractive option for companies navigating the changing semiconductor landscape.