Gas distribution systems in semiconductor fabs use ultra‑high purity stainless steel manifolds. These stainless steel manifolds are made from 316L VAR (vacuum arc remelted) steel. The interior of such stainless steel manifolds is electropolished to a mirror finish.

A helium leak test for stainless steel manifolds must show less than 1e‑9 scc/s. Each port on these stainless steel manifolds has a diaphragm valve. The welding of stainless steel manifolds for gas is performed in a cleanroom.

Stainless steel manifolds for hydrogen service require special purging procedures. The surface roughness of these stainless steel manifolds is Ra 0.25 µm. For toxic gases, stainless steel manifolds are enclosed in a ventilated cabinet.

The part number on stainless steel manifolds is laser etched to avoid contamination. A mass flow controller mounts directly on stainless steel manifolds. The dead volume inside stainless steel manifolds is minimized.

For specialty gases, stainless steel manifolds are baked at 250°C to remove moisture. The gasket for these stainless steel manifolds is nickel or Viton. A pressure transducer on stainless steel manifolds sends data to the control system.

Stainless steel manifolds with multiple inlets allow gas blending. The outlet of stainless steel manifolds goes to a valve manifold box. Regular verification of stainless steel manifolds includes residual gas analysis. Even a tiny leak in stainless steel manifolds is unacceptable in semiconductor manufacturing. Thus, these stainless steel manifolds are crafted with extreme precision.