Phosphine: Purer raw materials for the semiconductor industry

Did you know phosphine is an indispensable ingredient to manufacture everything from computers to LED lights? As the world-leading supplier of this material, Solvay has to keep up with increasing demand and stringent requirements.

There are three main applications for electronic-grade phosphine: it is used to manufacture LED lights (mostly the red and yellow portions of the spectrum), for certain types of high efficiency solar cells, and as a dopant for making semiconductors. Doping is the intentional introduction of impurities into an intrinsic semiconductor that allows conduction to occur. “For instance, in computer chips, phosphorus atoms are introduced to silicon wafers to create electrically conductive n-type semiconductors.” sums up Jeffrey Kolpa, Global Marketing Director for the Phosphorus Specialties business line.

 

Cypure-infographic

Near-perfect purity

One of the crucial requirements this product meets for customers’ applications is the need for high purity. Solvay markets two grades of phosphine: CYPURE®, which boasts a purity level of 99.9997%, and CYPURE® Ultra, which reaches 99.9999% purity. To achieve these levels, every detail from manufacturing to transportation is paramount, such as the absolute cleanliness of the cylinders used to ship the product.

“Our customers need increasingly purer raw materials as the computer chips they manufacture get smaller,” explains Mike DePalo, Global Business Director of Solvay’s Phosphine Gases product line. “Impurities in the phosphine such as moisture or metal are measured in parts per billion. They can negatively impact the chip. We also have to work to maintain impurities levels within a specific, narrow range, as irregularities can be  damaging, both to our business and our customers’.”

To this day, phosphine remains the molecule of choice in the semiconductor industry. You can’t make chips without a phosphorus atom; it’s just how the physics work.

Jeffrey Kolpa, Global Marketing Director for Phosphorus Specialties, Solvay

Computer chips to LED: Phosphine everywhere

Solvay’s Phosphine business comes from legacy Cytec (the company was acquired by Solvay in 2015); as such, the business unit has been selling high-purity phosphine since the 1980s. What’s changed since then? “Volumes have increased significantly, as today chips are just about everywhere, while LED technology has spread tremendously,” says Jeffrey. “To this day, phosphine remains the molecule of choice in the semiconductor industry. You can’t make chips without a phosphorus atom; it’s just how the physics work.”

Computer chip

In the LED market, as mentioned, chips made with phosphine produce red and yellow light, so for general lighting, nitrogen-based blue spots are what’s generally used. But there is one big market for LEDs using phosphine: giant display boards. “Every individual chip in the board can display three or four different colors: the red and yellow spots use phosphine,” explains Mike. “Generally speaking, the LED market is the biggest consumer of phosphine gas.”

That being said, whether it’s for computer chips or LEDs, only a couple of phosphorus atoms are required per item, so volumes in the market remain low overall. Also, this is an industry where the pressure to cut costs is constant, a pressure which is transmitted along to providers. But customers continue to trust Solvay, the leading player in this market, “above all for our consistency in quality and our world leading supply capacity. In an ever-increasingly competitive environment, we continue to leverage Solvay’s global position to ensure alignment with the evolving needs of our customers,” adds Mike. 

All in all, this is a small, niche market, but with consistently high growth, because as you now know, in our tech-driven world, phosphine is everywhere!