For semiconductor equipment manufacturers, there is only one cleanroom setting as thoroughly vetted as their own — that of their trusted, experienced service provider. ISO-compliant cleanrooms are essential for minimizing the impact of potential particle damage to the equipment — the level of rigor for environmental control cannot be understated. Whether manufacturing, assembling or repairing products, the same exacting air quality standards apply. That is where cleanrooms come into play, and it’s the reason it’s so important for original equipment manufacturers (OEMs) to ask critical questions before outsourcing services to a business partner.
In this article, we’ll explore the nature of the cleanroom market, the standards governing these state-of-the-art environments and what semiconductor equipment manufacturers should consider before outsourcing services.
The Rising Demand for Cleanrooms
While customers are willing to pay top dollar for mission-critical equipment, that investment comes with a caveat. They’re expecting products of the highest quality, which means they must function reliably, perform consistently and remain in good working condition throughout the promised product lifetime. They understand that the products they’re purchasing are built to last, and in doing so may need repairs from time to time as the components inside wear out, break or become obsolete, but that doesn’t dim their performance expectations. Instead, it adds another dimension. Not only do they expect high-quality semiconductor equipment, but they also expect high-quality repair services.
The demand for cleanrooms is on the upswing for a number of reasons. First, there’s an increased demand for semiconductors, driven by new and innovative products whose foundations are built on integrated circuits and the AI boom. Oftentimes, the capacity and capability to keep up with the operations required to support this technological growth in addition to legacy parts is limited. Further, the time required to build and properly qualify a cleanroom environment is certainly an investment, and there must be suitable ROI to justify doing so. To top it off, cleanrooms require a unique type of skilled, trained professionals to ensure safety and quality, which can be hard to come by amidst the global semiconductor talent shortage.
Cleanrooms provide an environment free from contaminants as they are manufactured, tested and packaged. With so many needs to fulfill, many with differing air quality requirements, modern environments are often zoned (divided into cells) using modular cleanrooms. This enables manufacturers to simultaneously tackle several activities or, in the case of a service provider, several different equipment types of various customers whose cleanroom requirements vary. Modular cleanrooms also make scaling manufacturing up and down much less of a burden as new products are introduced, reach peak production and eventually cycle down.
That doesn’t negate the need for expansive hardwall cleanroom environments, though. NASA’s high-bay cleanroom at the Goddard Space Flight Center in Maryland is often touted as the world’s largest. Used to assemble, test and integrate sensitive spacecraft add-ons such as the Hubble and James Webb space telescopes, it’s eight stories tall. While that’s obviously on the extreme end size-wise, the production of large-scale equipment in many industries requires spacious cleanrooms. All told, the cleanroom technology market (inclusive of consumables and equipment) should be closing in on $11 billion globally by 2030.
What is a Cleanroom?
Whether hardwall or modular, it’s important to understand what a cleanroom is and how they are classified. A cleanroom is a tightly controlled environment designed to filter out dust, microbes and particles that can damage the vulnerable, often complex equipment therein. High-efficiency particulate air filters (HEPA filters) are deployed to remove contaminants and pollutants from the air. Special surface treatments are used to prevent off-gassing and particle shedding. Protective clothing is worn to keep hair and skin cells from escaping the bounds of gowns, gloves and head coverings. Temperature, humidity, airflow and air pressure get their due attention, too.
The International Organization for Standardization (ISO) introduced the ISO 14644 standard to classify cleanrooms based on the maximum allowable concentration of airborne particles in each cubic meter of air. Cleanroom classification ranges from ISO 1, the most pristine, to ISO 9, with “9” still being cleaner than your average room.
To put that range in context, consider the ISO 5 cleanrooms in the middle of the pack. They provide air cleanliness levels with a maximum of 100 particles per cubic meter and require unidirectional, or laminar, airflow to create smooth, parallel layers of air movement with minimal turbulence. This unidirectional airflow essentially “scrubs” the air of contaminants, sweeping them away from sensitive areas. And all this happens after the air has passed through an extensive filter system on the ceiling. An exhaust system removes the particles from the atmosphere, creating a safe, clean environment for high-value, vulnerable equipment.
Who Uses Cleanrooms?
Any industry concerned with contaminants showing up in — or destroying — products will have a keen interest in cleanroom technology. While cleanroom requirements vary within and across sectors, here are some general uses by ISO classification:
- ISO 1: These ultra-sterile spaces may be used for nanotechnology applications and biotechnology research, but they are rare
- ISO 2: As with ISO 1, they are not often deployed, but may be used in biotech research and the manufacture of semiconductors and sensitive optics
- ISO 3: Typically found in aerospace, pharmaceutical and biotech facilities requiring stringent contamination control
- ISO 4: For applications common to the manufacture of thin film materials, displays and optics
- ISO 5: Suitable for pharmaceutical compounding, biotech research, semiconductor fabrication and medical device manufacturing
- ISO 6: Often deployed for food processing, semiconductor manufacturing applications or the production of surgical equipment or medical devices that will be placed within a patient’s body
- ISO 7: A moderately controlled environment widely used for electronics assembly and medical device manufacturing
- ISO 8: Often seen in post-production environments for packaging, assembly and the storage of packaged goods
- ISO 9: For activities where minimal — but still better than the general environment — air cleanliness standards suffice, such as office settings or general assembly lines
The Benefits of Cleanrooms for Semiconductor Equipment Manufacturers
The semiconductor industry is defined by rapid innovation in functionality and form factor, much of which is aimed at producing ever-more-powerful semiconductors at ever-more-microscopic sizes. Although “3nm” is a marketing term and not an indicator of actual size, suffice it to say that the most advanced semiconductors are very, very small. Fun fact: A skin cell is roughly 30,000 times larger than the smallest transistor. The impact of even the most minute contaminant can seem like dropping a boulder on a gnat. There will be damage. And miniaturization continues apace; 2nm is expected to be in wide use within the year.
Tolerance for defects is unforgiving on smaller semiconductors, but it’s not inconsequential on legacy chips, either. Thus, the production of semiconductor manufacturing equipment must match the requirements of the semiconductor OEMs themselves measure for measure. The benefits of cleanrooms for semiconductor equipment manufacturers include the following:
- Reliable control of the environment, including air quality, temperature, humidity, air pressure and flow, static and outgassing
- Consistent product quality in an environment where a single particle of dust can wreak havoc on silicon wafers and other sensitive materials
- Safer working conditions in environments where employees are often required to handle toxic materials
- Reduced risk of injury and costly product failure during production and after a semiconductor has been installed in a device
16 Questions to Ask Your Service Provider About Their Cleanroom
There are many different types of semiconductor equipment. Their air quality requirements may differ and they may even vary for different aspects of the manufacturing process. Before you sign on the dotted line to outsource these vital services, ask your potential service partner the following questions about their cleanroom:
1. How big is your cleanroom?
A cleanroom must be large enough to accommodate the processes expected of it, but there are other considerations as well. It must be able to house the materials, equipment and people required to do the work. Operating cost will be a factor, as will the feasibility and efficiency of the manufacturing process.
2. Can your cleanroom be easily configured, upgraded or expanded?
Modular systems allow “cleanrooms within cleanrooms” to operate independently of one another. This not only accommodates the different air quality and power requirements for different types of equipment at various stages of the manufacturing process, but also makes it easier to configure, upgrade and scale cleanrooms as needs evolve. Configurable, prefabricated cleanrooms have made significant inroads into the market and are projected to reach sales of $800 million globally by 2032.
3. What ISO classification does your cleanroom carry?
This straightforward question helps to ensure the ISO classification level matches what you intend to have done in the cleanroom. The applications outlined earlier are indicative of common requirements, but do your due diligence to ensure your specific use case is properly aligned to a service provider’s ISO level. Also, ask about varying classifications to accommodate different stages of the production/repair process or devices that require different levels of air purity.
4. What types of products does your cleanroom currently handle?
This can be indicative of ISO classification. It can also measure how prepared a service provider is to tackle product innovation, additional products in an OEM’s portfolio and fluctuating demand.
5. What service capabilities can your cleanroom accommodate?
Cleanrooms that support product manufacturing may have different ISO certifications than those that focus on assembly, packaging, warehousing or repairs. Gauge service capabilities accordingly.
6. Is your cleanroom temperature- and humidity-controlled?
While the primary focus of a cleanroom is air quality, temperature and humidity can significantly impact manufacturing and finished device storage, too. For instance, humidity affects condensation, microbial growth, corrosion and static electricity buildup, while temperature influences particle behavior.
7. Does your cleanroom run a particulate monitoring system?
Continuously measuring and monitoring the number and size of airborne particles is the only way to stay ahead of potential contaminant issues. Real-time data on air quality can detect when particle levels exceed — or are on the threshold of exceeding — particle limits.
8. Do you monitor the important environmental data of the cleanroom?
Beyond particle counts, measuring and monitoring temperature, humidity, air pressure and airflow are essential to ensuring that these and other factors remain within established environmental parameters, thus mitigating the risk of compromised products and noncompliance with regulatory standards.
9. Is the cleanroom fully integrated into your overall quality system?
Integrating the two enables service providers to continuously monitor and document the cleanroom environment more easily, minimizing the risk of contamination and ensuring consistent product quality throughout their whole operation. Look for documented protocols for cleanroom personnel processes as well.
10. Is a validated ultrasonic clean line attached to the cleanroom?
Sensitive manufacturing processes require a high level of cleanliness — and the key word here is “sensitive.” Ultrasonic technology enables cleanroom operators to use high-frequency sound waves to thoroughly clean the most delicate or convoluted components using cavitation bubbles to rid surfaces of dirt and contaminants. The ultrasonic clean line is the series of tanks that make it possible.
11. What training do people go through to work in the cleanroom?
Even seemingly mundane gestures can have immense consequences in the cleanroom. Training should incorporate contamination control principles, cleanroom protocols, gowning and entrance/exit procedures, proper material handling and cleaning techniques to minimize particulates and keep workers safe. Look for strict guidelines on movement and actions, as well as robust documentation. And make sure training isn’t simply theoretical; cleanroom workers should be required to practice what the company preaches.
12. Do you have specialized technicians working in your cleanroom?
ISO classification is an indication of what a cleanroom can accommodate, but technical specializations give you a clear picture of whether that’s feasible or not. Industries may require specific safety certifications. OEMs may require brand- or product-specific certifications of their own. Since technicians are in high demand and the scarcity of qualified people is well-documented, this is a question that cannot be ignored.
13. What are your gowning requirements?
As noted earlier, protective clothing such as gowns, gloves, booties and hoods keeps hair and skin cells from contaminating sensitive components. Requirements, including those for gowning sequence, fit and even personal hygiene, will vary based on cleanroom classification. Make sure your potential service provider’s protocols suit your needs.
14. How often is the cleanroom audited or tested?
ISO cleanliness standards and regulatory requirements govern how often a cleanroom should be audited and tested. Facilities with stricter ISO classifications (the purest in terms of air quality) may need to be inspected every six months. For the others, annual inspections may suffice.
15. How often does the cleanroom receive routine maintenance?
With so many complex and highly calibrated systems governing air quality in a cleanroom, weekly inspection and maintenance is a good rule of thumb. More frequent cleaning and maintenance checks are expected at the strictest ISO levels since the tolerance for air contamination is nil or close to it. In addition to systems maintenance schedules, look for daily surface and room cleaning protocols and air filter replacement schedules.
16. What is your cleanroom uptime?
Any interruption in cleanroom function is an invitation for compromise — and not the good kind. Cleanrooms should remain operational as close to 100% of the time as possible, with minimal interruption for necessities such as cleaning and maintenance. The sensitive processes going on inside demand a steady, tightly controlled environment, not one that resembles a rollercoaster ride.
Outsource Equipment Repair Services to an Expert Provider
OEMs contract with many types of service providers, but depot repair services require special consideration from a cleanroom perspective. Expert partners with the right cleanroom processes and technical capabilities not only ensure that your equipment is handled according to the highest quality standards, but also that it continues to perform at its peak for your customers.
Shyft Global Services offers OEMs the benefits of high-tech cleanroom environments that are compliant with numerous ISO and IT industry standards and maintain the strict controls and protocols required of the semiconductor manufacturing industry.
For more on how to choose the right service provider for your semiconductor manufacturing equipment, download “Solving the Top 7 Repair Challenges for Semiconductor Equipment” for a comprehensive overview of the engineering qualifications, meticulous calibration and technologically sophisticated equipment involved in the repair of semiconductor manufacturing equipment, along with the supply chain and logistics capabilities necessary to make it run smoothly.
About the Author
Steve Bair has been with the company since 1997 and currently serves as the Director of Global Engineering for the repair services organization within Shyft Global Services. He has extensive experience with and passion for product and services solution design, engineering, delivery and management. He has a proven track record in cross-functional leadership roles as well as weighing and balancing the objectives of the company and the customer to develop innovative solutions that solve complex business needs.
