MKS Inc spent four years proving it could carry the Atotech purchase without breaking the balance sheet. The second quarter is the first period in which that debt story and the AI electronics story finally run in the same direction. Semiconductor vacuum and radio-frequency content, chemistry equipment for advanced packaging, and flex printed-circuit drilling all accelerated together, which is a different setup from a one-segment bounce. The market already celebrated that mix once this year and then gave a large share of the gain back. The live question is whether cash generation and order visibility now justify treating the company as a compounding process franchise rather than a leveraged cycle name.
The June quarter cleared the top of the guided revenue band at $1,248 million. Year-over-year growth landed at twenty-eight percent, with every end market in double digits. Adjusted earnings before interest, taxes, depreciation and amortization printed $358 million. Free cash flow converted about fifteen percent of sales. Net leverage fell to three times trailing adjusted earnings. Those figures still need a caveat. Roughly one hundred basis points of reported gross margin came from tariff and duty refunds rather than mix. Convertible notes tripped their sale-price test and now sit as current liabilities. Capacity arrived as well: the Penang Supercenter opened in June, and a Guangzhou chemistry-equipment expansion is already on the calendar.
Management now guides the September quarter to about $1,350 million of revenue at the midpoint. Semiconductor is the swing factor, with implied year-over-year growth above fifty percent if the midpoint holds. Chemistry-equipment visibility stretches through next year, which is the strongest argument that this is not a one-print spike. The counterargument is the stock itself. Shares sit far below the mid-year high even after the beat, which means the market is already discounting a fade, a dilution event from the converts, or both. The next several quarters resolve whether operating cash keeps paying the term loan down faster than working capital and factory start-up costs absorb it.