Lam Research Corp.

Lam Research Corp. is an American semiconductor equipment manufacturer that designs and builds wafer fabrication tools for deposition, etch, and clean — the three process steps that define every chip's physical structure — with $18.44 billion in revenue in fiscal 2025. The company is one of the four dominant players in the global wafer fabrication equipment (WFE) industry, alongside Applied Materials, Tokyo Electron, and ASML, and has assembled an installed base of over 100,000 process chambers that generates a growing stream of service, spares, and upgrade revenue.

This is a story about the AI capex supercycle landing in Lam's wheelhouse. Three-dimensional device architectures — gate-all-around transistors, high-layer-count NAND, high-bandwidth memory stacks — require more etch and deposition steps per wafer, and Lam holds leading positions in both. After years of being viewed as the cyclical levered bet on semiconductor capital spending, the company is making a credible case that something structural has changed: each successive node now demands more of what Lam sells. The stock has re-rated accordingly, more than quadrupling from its mid-2025 lows to trade at nearly 68 times trailing earnings.

The file turns on a single question: whether the etch-and-deposition intensity thesis can outlast the cycle. If Lam's SAM (served available market) really does expand from the low-30s to the high-30s percent of WFE, and WFE itself sustains above $130 billion, earnings power compounds from here. If the current frenzy is just the sharpest upswing in a notoriously boom-bust industry, the valuation embeds a degree of optimism that prior cycles punished severely. The sections that follow give you the evidence to pick your side.