Abstract: A valve comprising a valve body including an inlet, an outlet and a mounting surface. A first valve actuator is connected to the valve body. A plurality of mounting holes are formed in the mounting surface. The plurality of mounting holes are asymmetric relative to the mounting surface.

Abstract: A Chemical Vapor Deposition (CVD) tool providing more even flow and distribution of reagent gasses over a substrate. The CVD tool includes a processing chamber and a shower head. The shower head includes a gas dispensing surface having multiple hole patterns that are preferably, but not exclusively, non-symmetrical patterns that mitigate or eliminate lines or symmetry. Such hole patterns include are a variety of different types of spirals or close approximations thereof, include, but are not limited to, Archimedean, Vogel or Fermat spirals.