A Comprehensive Analysis of Pressure Monitoring in Semiconductor Fabs

As an increasing number of artificial intelligence achievements come to the fore, the development of the semiconductor industry has become a pivotal battlefield for global technological competition. While the 2nm process has become the finish line of the industry race, the "precision war" in semiconductor cleanrooms has long since begun—the number of particles per cubic meter of air must be controlled to single digits, and a pressure fluctuation of just 0.1Pa can result in the scrapping of an entire batch of wafers. Today, we explore how Endress+Hauser has delved into the subject of "pressure monitoring" to help safeguard the precision goals of semiconductor fabs.

In a semiconductor fab, the single-project usage of pressure transmitters can reach 3,000 to 12,000 units, covering all scenarios including cleanrooms, pure and wastewater treatment, and gas distribution.

Maintaining a micro differential pressure gradient of 5–10Pa across different cleanroom zones is the key to preventing cross-contamination. The Endress+Hauser Deltabar PMD75B differential pressure transmitter boasts a standard accuracy of 0.05% (0.035% for platinum-grade accuracy). It can be adjusted via Bluetooth to a measuring range of -50~50Pa for high-precision micro differential pressure monitoring, ensuring the cleanliness requirements of cleanrooms are met.

Calibration reports show the actual measurement error is ＜0.014Pa.

In the HVAC systems of cleanrooms, the pressure in exhaust ducts typically ranges from -3,000 to -1,500Pa, and the corrosiveness of acid-base waste gas poses a huge challenge. The Endress+Hauser Deltabar PMD55B, equipped with sensors with Alloy C276 diaphragms or PMC51B ceramic diaphragms, can easily resist corrosion. In an exhaust gas application at a semiconductor fab in Shanghai, it has successfully achieved stable data output with a tolerance of ±10Pa and automatic alarm when the pressure exceeds 50Pa, completely solving the problem of uncontrolled fan flow rate.

Ultra-pure water systems demand "zero contamination" and non-metallic wetted parts. The Endress+Hauser Cerebra PMC51B adopts a 99.9% high-purity ceramic diaphragm with a dry, oil-free design that fundamentally avoids leakage. It offers optional non-metallic wetted materials, especially PVDF (polyvinylidene fluoride), to meet chemical compatibility requirements in semiconductor ultra-pure water processes. Meanwhile, the ceramic diaphragm features a self-monitoring function: in the event of diaphragm damage or medium leakage, the self-monitoring system provides rapid fault feedback to ensure uninterrupted system operation.

Wastewater in the semiconductor industry often contains highly corrosive hydrogen fluoride, presenting extreme challenges for wetted materials. The Endress+Hauser Cerebra PMP51B, with a special coating, can specifically address corrosion issues. Its application in a fluorine-containing wastewater project at a semiconductor fab in Zhejiang has successfully solved the pain point of diaphragm bulging or rupture that plagues similar pressure transmitters in corrosive environments.

Processes such as etching and thin-film deposition require a high-vacuum environment. The Endress+Hauser Cerebra PMC51B ceramic pressure transmitter adopts the capacitive measurement principle, is resistant to high vacuum with a minimum measurable absolute pressure of 0.1Pa, and is capable of providing accurate data support for the 2nm manufacturing process.

High-purity specialty gases with a purity of over 99.999% impose stringent requirements on sensors. The Endress+Hauser Cerebra PMP51B, paired with VCR fittings and an EP (electropolishing) finish, meets the pressure monitoring needs of high-purity gas distribution in specialty gas cabinets. Its flexible diaphragm seal system with special material diaphragms fulfills the rigorous requirements of different corrosive chemicals, enabling pressure monitoring of chemical storage tanks.

From the birth of a single chip to the upgrading of the entire semiconductor industry, the precision and reliability of pressure transmitters have always been the "invisible cornerstone" behind the scenes. As we pursue the boundless frontiers of chip technology, these silently operating "pressure stewards" are the vital force safeguarding our course. From micro differential pressure control in cleanrooms to safety monitoring in waste gas treatment, from zero-contamination guarantee for ultra-pure water to precise delivery of specialty gases, Endress+Hauser pressure transmitters have always stood at the "precision frontline" of semiconductor intelligent manufacturing, escorting pressure measurement and providing professional, safe and efficient intelligent solutions.