The biggest challenges with semiconductor cleanroom design in 2024

Published: 5-Mar-2024

A look at three major challenges facing the semiconductor cleanroom ecosystems, lead times, portability, and short-term flexibility. Davis Verheyen from Instant Cleanroom Solutions (ICS) analyses these challenges

Even before President Biden signed the bipartisan CHIPS and Science Act into law in August of 2022, chipmakers had already begun to build new fabs in the US.

This was spurred, in part, by the chip shortages that occurred during and after the global COVID-19 Pandemic, but it is also in recognition of the ever-growing demand for semiconductors in the national and global market.

Since 2021, a full dozen new fabs have been announced or begun construction in the US with Arizona, New York, and Texas being the locations for the majority. Expected completion dates range from this year through 2025.

Spurred on by the American legislation with its $53 billion USD directed to “American semiconductor research, development, manufacturing and workforce development” and the industries' response of investing $50 billion USD as of late 2022, the EU earmarked 43 billion Euros (approximately $47B USD) for a similar plan, the European Chips Act.

This has collectively resulted in an extraordinary demand upon – and for – what may be considered “the support cleanroom ecosystem.”

More than just big buildings

The fabs being built for TSMC, Intel, Samsung and others can each require 100,000 to 600,000 square feet of cleanroom space.

Each of these ISO Class 4 or 5 areas requires components that themselves are manufactured, precision cleaned and assembled in a cleanroom of equal cleanliness.

As impressive as the megastructure fabs rising from the Arizona desert and elsewhere are, the overwhelming majority of cleanrooms that are classified as “semiconductor cleanrooms” are owned and operated by smaller subcontractors supporting the construction and operation of their larger brethren.

It is estimated that for every one square foot of wafer production cleanroom space, there is an infrastructure of roughly 50 square feet of cleanroom space needed to build or support it. Hence, the “the support cleanroom ecosystem.”

US$300 billion worth of projects are currently in every stage of development

Global market intelligence provider Industrial Info Resources has tracked that more than US$300 billion worth of projects are currently in every stage of development from early planning to well underway in construction.

Everything from the tooling used in the fab to the piping that transports ultra-pure water and gases that are used in the manufacturing process comes from a smaller contractor.

This relatively sudden increase in demand is presenting new challenges for these smaller firms as they try to take part in this “new Renaissance of US semiconductor manufacturing” while having to simultaneously upscale their own capacity so that they can meet their clients’ deadlines.

We at Instant Cleanroom Solutions (ICS) have had numerous conversations with our clients who are serving the semiconductor industry. The takeaway from these discussions is that the challenges being faced by the smaller support companies fall along three main lines: Lead Times, Portability and Short-Term Flexibility. 

Lead times

Finding skilled technicians is an ongoing concern even in the best of times.

But it has taken on extra intensity given that multiple companies are heavily recruiting from the same limited labour pool.

Once a technician has been hired, it takes additional time for them to be brought up to speed on the processes and procedures of their new company’s operations. 

Beyond that, however, is having a space for them to work. Whether crafting subassemblies on-site, or building and shipping from the company’s permanent location, many contractors are finding that they need to add to their cleanroom space sooner rather than later.

Of course, constructing a new building takes time measured in months or years, but even setting up a pre-fabricated, hard-sided modular clean room within an existing warehouse can require more lead time than the deadline allows.

This pain point can be especially acute when working within the tight schedules many of the prime building contractors are demanding.

Knowing the reputation of the cleanroom provider is critical to protecting one’s company’s reputation

A sudden realization that more cleanroom space will be required within the 2-4 week window has caused more than one contractor to fall for the websites promising soft-wall cleanrooms that will “ship tomorrow” only to find out after the order is placed that the room will ship in eight weeks and will require another two weeks to be set up and operational. 

This is clearly an area where shortcuts or “taking it on faith” that the room will meet requirements are clearly unacceptable.

An incorrect installation can compromise the cleanliness of the component. A piece of airborne contamination can compromise the quality of a precision orbital weld, this can lead to a leak or FOD (Foreign Object Debris) that could shut down a production line with costly delays. 

A pair of relatively recent developments within the cleanroom industry has made overcoming this challenge easier.

Inflatable softwall “instant” cleanrooms and semi-trailer-based mobile cleanrooms (both innovations of ICS) allow the expansion or deployment of cleanroom space within a matter of days depending on required configuration.

The former can be set up in within nearly any enclosed structure, while the latter can be positioned practically anywhere reachable by a semi-tractor-trailer rig – whether at the construction site, or in the parking lot of the contractor’s main facility.

In addition to the crucial choice of cleanroom solution and the location of operation, of equal importance is the quality of the provider of the solution. For the safety and quality reasons mentioned earlier, knowing the reputation of the cleanroom provider is critical to protecting one’s company’s reputation.

Portability

The construction of the actual fab can take three years. A fab will require a minimum of 25 miles of process piping for the ultra-pure systems – both gaseous and liquid.

All of that piping needs to be assembled, and just as importantly, cleaned to ensure that nothing within it can contaminate the materials that flow within it. To ensure consistent quality and safety, the piping sections are joined using orbital welding.

While off-site assembly of subsections is possible, it introduces the risk of in-transit contamination as well as the need for re-work due to variations as the fab is constructed.

Off-site assembly adds to the lead time needed to ensure that the parts arrive on schedule. To counter this, many contractors set up portable cleanrooms on the construction site.

The portable cleanroom allows the contractors to better coordinate with the prime contractor(s), enabling improved responsiveness as they are often mere feet from the installation location. 

For most subcontracting piping companies, a rental unit that can be returned after the work is done, is both time-saving and the most economical option.

Even with on-site delivery times as low as one week, it is important that a contractor reserves one to ensure its availability

However, with such megaprojects as a fab, the competition for available, quality portable cleanrooms is something to be taken into consideration. As mentioned earlier, the cleanroom must be at least equal in terms of cleanliness as the ISO rating of the cleanroom that the piping will be installed into.

For the orbital welding process, the cleanroom must be able to support the equipment’s need to exclude moisture and oxygen within the argon gas environment where the welding is physically taking place.

Of course, the cleanroom itself must also be big enough to accommodate the largest or longest set of piping to be delivered under contract. Attempting to assemble new piping while precision cleaning the completed subassemblies in too small of a space creates inefficiencies while also raising the likelihood of human error.

Mobile cleanrooms address a majority of those concerns, being pre-configured to meet the ISO 5 thru ISO 8 standards, they allow easy installation and integration of needed equipment and up to 1,000 square feet of useful space.

However, even with on-site delivery times as low as one week, it is important that a contractor reserves one to ensure its availability.

Short term flexibility

For most contractors working on a project in support of a semiconductor fab, the need for added “surge” cleanroom space does not warrant a long-term investment.

The scope and duration of the work to be performed is well defined in the contract. Purchasing a hard-sided, or even a soft-sided, framed clean room for a project that will last a few weeks is an expense that can cut deeply into the profits earned.

There is the additional concern of storing the unit once it is disassembled after use. In addition to taking up limited space, the components of the cleanroom would need to be stored in such a way to ensure that they are not damaged, completely wiping out the value of the investment.

Again, rental units resolve this challenge. Should additional temporary cleanroom space be needed once more, it can be delivered within a few days with the assurance that it has been properly maintained and will meet requirements.

For placement within an existing structure, an instant cleanroom takes this convenience and timeliness further as it only requires a pair of workers to erect within a matter of hours, as compared to 3-5 days for a team of four or more workers putting up a framed soft-sided cleanroom, who will also need the use of a forklift.

Overcoming the biggest challenges

As with most things in life, planning ahead can reduce the size of the challenges being faced by contractors supporting the current boom in semiconductor cleanroom construction.

Having a firm grasp on the logistical and infrastructure requirements needed to meet the contract is the beginning. Careful analysis of schedule and workflow will reveal whether additional cleanroom space will be required to meet deadlines and quality targets.

This allows decisions about sourcing – and which cleanroom solution is optimal – to be made clearly rather than as part of a last-minute scramble. The end result will be more efficient – and profitable.

You may also like