Ion Pump Operation
What are Ion Pumps?
Ion pumps are electro-physical vacuum pumps that remove gases from their environment by turning them into solid materials.
How do Ion Pumps work?
Ion pumps use a four-step process to remove gases from the vacuum chamber.
Step 1: Create a high magnetic field
The ion pumps have magnets located outside the vacuum. Those magnets generate a 1200 gauss magnetic field, which contains and guides electrons within circular anode rings.
Step 2: Generate a plasma
After an initial rough pumping to remove much of the gas, high voltage is applied to the element assembly. Electrons are pulled into the anode tube assembly where they spin in a cloud; this cloud is commonly referred to as plasma. The plasma is trapped by the high magnetic field.
Step 3: Ionize gas molecules
As gases move into the anode assembly, electrons strike the gas molecules. This collision removes electrons from the gas molecule's valence shell, and changes the gas molecule into a positive ion (it has a positive charge). The positive ion is forced out of the anode tube by the high voltage field at a high velocity toward the cathode plate.
Step 4: Capture gas ions
When the positive ion strikes the cathode plate, that impact is called sputtering. Cathode materials are ejected toward the anode tube and the ion chemically and physically reacts with the cathode material.