ACM Research makes semiconductor capital equipment, primarily wafer cleaning tools and electrochemical plating (ECP) equipment, selling almost entirely to chip fabs in China. Wafer cleaning — which removes particles and residue from silicon wafers at multiple steps in the fabrication process — accounts for roughly 70% of revenue. ACM's cleaning portfolio is built on three proprietary technologies: SAPS (megasonic cleaning for flat and patterned surfaces), TEBO (damage-free cleaning for high-aspect-ratio structures), and Tahoe (high-temperature sulfuric peroxide cleaning that uses less chemistry than conventional tools). ECP, which deposits copper and other metals onto wafers in both front-end fabrication and advanced packaging, is ACM's second-largest product line, where the company claims over 40% market share in China. ACM sells individual tools directly to fabs, with prices ranging from roughly $0.5M to over $5M. Revenue is recognized on customer acceptance for first tools and on shipment for repeat orders. ACM's four largest customers account for over half of revenue. The company spends 15%-18% of revenue on R&D — well above larger global peers — arguing that technology differentiation is its primary defense against lower-cost Chinese domestic competitors. ACM is also expanding beyond cleaning and ECP into furnace, PECVD, and Track equipment, all of which are early-stage. Longer term, ACM is targeting geographic diversification, with tool installations in Singapore, evaluations in Korea and Taiwan, and a new facility in Oregon, aiming for a long-term revenue target of $4B split between China and international markets.