AXT AI semiconductor revenue hits record $47.6 million on optical demand

The record performance at AXT highlights a critical bottleneck in the streaming and AI ecosystem: the physical layer of data center connectivity. As streaming platforms integrate more generative AI and high-bitrate processing, the demand for indium phosphide substrates becomes a leading indicator for infrastructure readiness. This shift toward 1.6T optical transceivers suggests that the next phase of data center scaling will prioritize throughput over raw compute volume. While competitors like Amtech Systems are gaining ground in advanced packaging, AXT’s vertical integration and capacity expansion through 2027 position it as a primary gatekeeper for high-speed optical hardware. Watch for upcoming China export permit updates as a potential headwind for these specialized substrate supply chains.

AXT's record quarter reflects a broader surge in indium phosphide substrate demand across the AI data center supply chain. The company's Beijing subsidiary, Tongmei, has been scaling production capacity to meet orders from optical transceiver makers serving hyperscale operators. In early 2025, AXT announced plans to expand its indium phosphide substrate manufacturing capacity by more than 50% through 2026 to address what it described as a structural supply shortage driven by 800G and 1.6T transceiver adoption. Coherent, one of the largest consumers of InP substrates for its datacom laser and detector product lines, reported in its fiscal Q3 2025 earnings call that datacom transceiver revenue grew over 80% year over year, driven by AI cluster interconnects, underscoring the downstream pull that benefits substrate suppliers like AXT. Lumentum similarly flagged strong demand for its InP-based components in AI networking applications during the same period.

The competitive landscape for indium phosphide substrates remains concentrated, with AXT, Sumitomo Electric, and JX Nippon Mining & Metals controlling the majority of global supply. AXT's TrueFlat technology, which reduces wafer bow and improves yield for epitaxial growth, gives it a differentiated position among substrate vendors. However, the company faces regulatory exposure: China's Ministry of Commerce has required export permits for gallium and germanium products since August 2023, and indium phosphide substrates fall under related scrutiny given their strategic classification. AXT has been navigating this by shipping finished substrates from its Tongmei facility in Beijing under existing permits, but any tightening of export controls could disrupt supply to Western transceiver makers. Amtech Systems, which supplies thermal processing equipment used in compound semiconductor fabrication, reported fiscal Q3 2025 revenue of $32.1 million, with its semiconductor equipment segment growing 22% sequentially, reflecting capital expenditure increases at compound semiconductor fabs that also benefit AXT's ecosystem.

Technical benchmarks for indium phosphide in AI networking continue to improve. The transition from 400G to 800G optical links, now standard in new AI cluster deployments, requires InP-based lasers operating at 100G per lane. Looking ahead, the IEEE 802.3df standard ratified in 2024 specifies 200G per lane for 1.6T Ethernet, which will demand higher-performance InP substrates with tighter specifications on carrier concentration and etch pit density. AXT's 4-inch and 6-inch InP wafers are qualified by major epitaxy houses for these applications. The company's vertical integration, from raw indium sourcing through crystal growth to polished substrate delivery, positions it to capture margin at each stage as the 1.6T upgrade cycle accelerates through 2026 and 2027. This growth is mirrored by as hyperscalers race to build out the necessary infrastructure, a trend further supported by .