AXT doubles indium phosphide capacity as $100M backlog signals AI demand

AXT Inc. plans to double indium phosphide capacity by the end of 2026 and again in 2027, betting that its $100 million-plus backlog reflects a multiyear AI-driven demand cycle for optical networking substrates.

"We are seeing unprecedented demand from AI data centers for indium phosphide substrates, and our brownfield expansion strategy allows us to scale faster and with lower risk than competitors," management said in a statement accompanying the capacity announcement.

The company is repurposing former gallium arsenide manufacturing space within its existing Beijing footprint, a brownfield approach that shortens deployment timelines and reduces construction risk. AXT designs and builds its own crystal-growth furnaces and recently invested in high-purity indium refining, strengthening control over critical raw materials. The company completed a $632.5 million funding round specifically for the expansion.

AXT controls an estimated 60 percent to 70 percent of the global indium phosphide substrate market, according to industry data. With customers including Nvidia, Google and Microsoft, the company's ability to deliver on its capacity targets will determine whether AI optical interconnect supply chains face a bottleneck in 2027.

The expansion strategy stands apart from peers pursuing greenfield projects. By building within existing facilities, AXT lowers construction risk and supports faster production ramp-ups. Management argues this creates a meaningful competitive advantage — scaling indium phosphide production is technically challenging, and converting capacity into high-quality wafer output requires specialized expertise that competitors lack.

The company's vertical integration extends beyond manufacturing. AXT designs and builds its own crystal-growth furnaces and maintains internal access to critical raw materials through affiliated supply-chain businesses. Recent investments in high-purity indium refining further reduce dependence on external suppliers while supporting margin expansion as volumes increase.

Global indium phosphide supply remains critically constrained. Industry estimates project global InP substrate shipments of 600,000 to 700,000 units in 2025, while actual market demand is estimated at 1.5 million to 2 million units — a supply gap exceeding 70 percent. The three companies controlling 80 percent to 90 percent of the market — Sumitomo Electric Industries, JX Metals and AXT — face expansion cycles exceeding two years for new capacity.

Peer capacity strategies diverge. Applied Materials Inc. has nearly doubled its manufacturing capacity through expansions in the United States and Europe and a new center in Singapore, with customers providing rolling eight-quarter forecasts. The company expects semiconductor equipment revenue to grow more than 30 percent in 2026. Allegro MicroSystems Inc. is taking a different approach, expanding through technology investment and design-win growth rather than large manufacturing buildouts, with data center content per rack expected to rise from about $150 to more than $425 in next-generation AI architectures.

AXT shares have surged 578 percent year to date, far outpacing the industry's 60 percent gain. The stock trades at a forward price-to-sales ratio of 42.91, significantly above the industry average and its five-year median of 1.48. The Zacks Consensus Estimate for fiscal 2026 earnings implies a 168.3 percent improvement from the prior year.

AXT's capacity expansion positions it as a key enabler of the AI optical networking buildout, but the valuation — a forward P/S of 42.91 with a Value Score of F — leaves little room for execution missteps. The company's production lines are primarily located in China, introducing geopolitical supply-chain risk. If AXT delivers on its 2026 and 2027 capacity targets, the revenue growth could justify the premium; any delays would expose the stock to significant downside given current expectations.

This article is for informational purposes only and does not constitute investment advice.