Calls for improved airborne molecular contamination control strategies resonate with industry insiders and political leaders alike. After all, global competition to produce the majority of the world’s semiconductors could also usher in a nation’s self-reliance.

That’s largely why the U.S. passed the CHIPS and Science Act of 2022. During the pandemic, semiconductor fabrication plants were sidelined due to Covid infections as well as contamination at the molecular level.

The CHIPS and Science Act of 2022

The CHIPS act offers upwards of $39 billion to companies that manufacture semiconductors in the U.S., adds $13 billion for R&D, as well as workforce training, and tax credits of 25 percent for new investments. This effort intends to bring semiconductor fabrication back to the United States to create jobs and protect our national security.

  • CHIPS investments will help make the U.S. the home to five of the world's "leading-edge logic chip" and DRAM semiconductor manufacturers—No other economy in the world has more than two of these facilities.
  • Today, U.S. fabricators make 0% of these chips.
  • With this funding, the U.S. is expected to manufacture nearly 20%-30% of the world's leading-edge logic chips by 2032.
  • Current projects include 16 new semiconductor manufacturing facilities, which are expected to create over 115,000 manufacturing and construction jobs across the United States.

While the taxpayer money and incentives being thrown at domestic production, investors would be well served to channel resources into mitigating airborne molecular contamination. Without effective contamination deterrents, semiconductor plants could turn into money pits.

What is Airborne Molecular Contamination?

Commonly called “AMC,” Airborne Molecular Contamination refers to harmful molecules that can negatively affect the manufacturing of products or processes. This term has become a trending issue in microelectronics circles in recent years, particularly in semiconductor fabrication plants.

Even minuscule amounts of AMCs can render the thin semiconductor wafer materials useless. That, in turn, renders millions of microchips and components defective. These are types of AMC that pose a danger to semiconductor manufacturing.

Internal AMC Sources

It may come as something of a surprise, but the very people who work in cleanroom fabrication facilities are a source of contamination. Human beings naturally give off ammonia, organic acids, and other materials like hair and dander.

Some are picked up by touching each other, walls, furniture, or sanitized disposable personal protective clothing. Once an AMC has cross-contaminated a fabrication tool or a wafer, it can spread.

External AMC Sources

Without comprehensive AMC mitigation for cleanrooms, fabrication plants are at the mercy of the local environment. Things like road construction, automobiles, power plants, and other manufacturing facilities send toxins airborne that can be sucked into cleanrooms through inadequate ventilation systems. It may sound counterintuitive, but lakes, rivers, streams, woodland areas, fields, and other natural environments emit AMCs naturally.

Industries Where AMC Mitigation is Critical

Although the discussion of AMC mitigation for cleanrooms tends to focus on semiconductors, wide-reaching industries continue to look at the problem and implement the latest solutions. High-level sterility is essential for the creation of other products and the processes that ensure functionality. These include the following.

  • Pharmaceuticals: Microscopic contamination can ruin the integrity of medications. Similar to the cleanrooms semiconductor fabrication plants rely on, pharmaceutical companies are tasked with AMC mitigation in research spaces as well as production.
  • Medical Device Sector: The crafting of delicate medical devices can also be negatively affected by AMCs. Along with dust and other particles, microorganisms such as bacteria, viruses, and fungi threaten their sterility.
  • Aerospace: The components employed in aerospace production require clean surfaces. Direct or cross-contamination can lead to defects.

When companies discover they have taken a “hit,” as semiconductor insiders like to say, it’s well after the fact. That means millions of dollars are lost, order setbacks occur, and quality control professionals need to re-examine the ways they approach sterilized processes.

Airborne Molecular Contamination Control Strategies

Businesses that integrate airborne molecular contamination control strategies engage in ongoing monitoring and detection. But, first and foremost, they use techniques to deter threats from entering the premises. These are AMC mitigation methods worth considering.

1: Process Optimization

Conduct thorough due diligence to identify potential contamination sources. In microelectronic fabrication plants and others, chemical reactions and solvents turning into vapor are often culprits. One efficient strategy involves minimizing their presence to only necessary uses. Reducing the number of spills and applications inherently lowers the amount of vapors in an environment.

2: Rethink Materials

Volatile organic compounds (VOCs) release gases into the air. Conduct a review of materials that are prone to VOC contamination and replace them with low-outgassing options whenever possible.

3: Reduce Potential Cross-Contamination

Creating a closed-loop system remains a tried-and-true solution to mitigating cross-contamination. This approach can be effective in terms of managing human, equipment, and materials contamination mitigation. However, it does not necessarily address the shipment of tainted semiconductor wafers.

4: Effective Ventilation

Building codes require employees to receive adequate amounts of clean, fresh air during the course of their shifts. This poses a significant problem for the cleanrooms and sterilized spaces.

The use of high-efficiency particulate air (HEPA) filters has emerged as an industry standard practice in many facilities. Their ability to capture contaminants at the molecular level makes them an ideal solution. Carbon filters are also essential for absorbing gaseous molecules.

5: Positive Pressure Sourcing

In terms of protecting against AMCs, integrating positive pressure sourcing ranks among the top innovative solutions. Positive pressure cleanrooms control workspace air by employing greater internal pressure than that outside of the room. By pressure-forcing clean air outwards and stopping contaminants from entering its resources, cleanrooms receive freshly ventilated air through the system that originated from a sterile source.

6: Monitoring and Detection

Instruments such as a mass spectrometer, photoionization detector, chemiluminescence analyzer, and others are crucial in the fight to detect AMCs. Air quality assessment devices provide high-sensitivity monitoring and detection that allow fabrication plants to halt processes and conduct an examination. They also offer contamination evidence that quality control professionals can use to rethink the AMC mitigation in cleanrooms and other spaces.

7: Personal Protective Equipment (PPE)

Disposable personal protective garments and the process of adorning and doffing are mission-critical when it comes to AMC mitigation in cleanrooms. Sterile PPE such as low-linting coveralls with hoods, gloves, accessories such as breathable masks, beard restraints, tight-fitting gloves, and footwear minimize the risk of human contaminants impacting semiconductors, chemical production, tools, equipment, surfaces, and air quality.

Before entering cleanrooms, staff members require a designated area to strip off street clothes, practice hygiene, and adorn disposable protective clothing in a separate and distinct controlled environment.

The reverse process is also essential to ensure researchers and people working with potentially hazardous materials do not track pollutants out of the facility. Stockpiling low linting disposable protective clothing is a great addition to your airborne molecular contamination control strategies necessary for advanced quality control.