GR020
Principle of operation
Attotech's GR020 pulse valve is designed to precisely inject gas in a vacuum chamber. Both the timing and the amount of gas released can be finely tuned.
The pulse valve is driven by a piezo electric disc (PZD) on which a small poppet is tightened. It opens and closes a 1 mm diameter hole where the gas flows. The moving parts are kept as light as possible, which makes opening times as short as 30μs feasible. The PZD and the poppet are mounted inside the valve body where backing pressures up to 5 bars can be applied. The valve opens when applying a voltage to the PZD and the backing gas flows in the 1 mm pipe through the body. The amount of gas is controlled by the voltage applied to the PZD. At the end of this pipe the target is tightened to the body by two screws. The target is decoupled from the moving parts; this makes the switch between targets very easy, and allows for custom-made target designs.
The valve is driven by a voltage gate produced by our piezo valve drive unit, DU001, together with a delay generator, or other pulsed high voltage power supplies. A 120μs electrical gate corresponds to a mechanical opening time down to 30μs. The body of the valve is cooled by a water cooling circuit.
The GR020 pulse valve