Besides the above 6, there are also:

1️⃣Kokusai Electric: TYO6525
Batch film formation/heat treatment, key thin film processes for 3D NAND and DRAM
Its main products are batch film formation equipment and film quality improvement equipment, with a leading global market share in the film formation equipment field.
In 3D NAND, increasing the number of stacking layers means repeating multiple film formations and heat treatments on the same batch of wafers. Kokusai's batch LP‑CVD/ALD equipment is suitable for efficient production of high-layer-count NAND. The company has disclosed that the Chinese market already accounts for about 40% of its revenue, mainly driven by capacity expansion needs for memory, logic, and power (28nm and above).
2️⃣Onto Innovation $ONTO:
Inspection/metrology + software, yield tools for memory and advanced packaging
3️⃣Ichor Systems $ICHR:
Gas and chemical delivery subsystems, the "blood vessels" of etching/deposition tools.
Its products include gas supply systems, chemical supply modules, fluid delivery systems, valves, connectors, and high-precision mechanical subassemblies. Main customers are front-end equipment OEMs and IDMs.
4️⃣Ultra Clean Holdings $UCTT:
Key subsystems + component cleaning services, spanning the supply chain of multiple equipment manufacturers
Its business is divided into two segments: Products and Services.
-Products: Design and manufacture gas delivery systems, chemical delivery modules, fluid delivery systems, precision robotic systems, process modules, and high-level assemblies, used in etching, deposition, and other integrated tools.
-Services: Provide ultra-high-purity cleaning, recoating, lifetime extension, and micro-contamination analysis services for tool components, targeting the WFE market of wafer fabs and equipment manufacturers.