What is a PLV or piezoelectric leak valve?
A Piezoelectric gas doser or leak valve is used when scientists need extremely precise control of gases being injected into a chamber where a chemical or physical reaction will take place.
High-end models use all-metal UHV compatible valves and are regulated by a Piezoelectric crystal stack. Applying a voltage to the stack causes it to extend, lifting a ceramic plunger, which allows gases to enter into the chamber in a controlled manner. When the voltage is removed from the crystal stack, the ceramic plunger is sealed to a valve seat by a high-tension spring.
Standard models are manually controlled. Advanced models use a computer to control the application of the voltage, allowing pulses as short as 20ms to be injected into the process or chamber. This is useful for gas doping applications where small amounts of gas are needed and large amounts may overpopulate the gases in the chamber. It is most useful when it is a reactive action.
PLV’s are used for gas dosing, MBE gas introduction, Surface Science applications, gas ion guns, gas pulsing, system pressure control and other areas where high precision and control are needed, especially in the low flow regime.
Oxford Applied PLV1000 has a Leak rate controllable from >12sccm to 1X 10-6 sccm and is available with flanged or VCR type fittings. Click here to learn more about the PLV1000