Axcelis designs, manufactures, and services ion implantation equipment used in semiconductor chip manufacturing. Ion implantation is a step in chip production where dopants are injected into silicon or silicon carbide (SiC) wafers to create transistors, and virtually every chip requires multiple implant steps. Axcelis sells its Purion family of ion implanters — in high current, medium current, and high energy configurations — directly to chip manufacturers through its own global sales force. The company's largest end market is mature node chips (28nm and above), including power devices, image sensors, and analog chips, with a growing focus on SiC-based power devices used in EVs and industrial applications. Axcelis also has smaller but growing exposure to DRAM memory and advanced logic. Revenue is split between systems (~68%) and an aftermarket business called CS&I (~32%), which sells spare parts, consumables, upgrades, and services tied to roughly 3,400 installed tools across 27 countries. CS&I carries above-average margins and is a natural hedge to the cyclicality of systems revenue, since customers tend to invest more in maintaining and upgrading existing tools when they slow capex. China has been the largest single geography in recent years. Axcelis has a pending merger with Veeco Instruments, which would expand the combined company into laser annealing, ion beam deposition, MOCVD, and other semiconductor equipment categories.