Technology

Principle

Like sputtering equipment, when the pumping capacity for argon determined the regeneration cycle of the cryopump, the cryopump can pump again after discharging only the argon and hydrogen from the cryopumps.

Hydrogen becomes a gas easily and is released when the temperature is raised above 50 K. Argon liquefies when the temperature is raised above 100 K. A method of regenerating a cryopump by discharging gaseous hydrogen and liquid argon while maintaining the cryopump in a low-temperature state is rapid low-temperature regeneration.

However, since water is left as ice in the pump(the temperature is raised to room temperature when the amount of water increases.), normal regeneration is required.

Low-temperature regeneration requires a mechanism for discharging liquefied gas from a cryopump. (Figure 2-1)

In the low-temperature regeneration, it is not necessary to raise the temperature to room temperature, so the time of temperature rise is short. Moreover, since cooling starts from a low-temperature state, the regeneration time can be remarkably shortened.

In a test of rapid low-temperature regeneration which was performed using a 12" type cryopump, the cryopump was ready for pumping within 1 hour after shutting down it. As in this example, in the case of sputtering equipment, the regeneration time can be drastically shortened by rapid low-temperature regeneration. ( 1/4 to 1/5 of normal time)

In addition to the sputtering equipment, in the case that the regeneration cycle is determined by a condensable gas other than water, the rapid low-temperature regeneration is very effective to reduce the regeneration time drastically.

Figure2-1: Example of a pumping system of rapid low-temperature regeneration

rapidlowtemp1.png
HVP:Hydrogen vapor pressure thermometer PG4:Ionization gauge for vacuum chamber V4:Roughing valve.
PG1:Pirani gauge for cryopump V1:Main valve GV:Gate valve(Ar discharge valve)
PG2:Ionization gauge for cryopump V2:Cryopump roughing valve VV:Discharge valve
PG3:Pirani gauge for vacuum chamber V3:Vacuum chamber roughing valve PV:Introduction valve

Figure 2-2:Comparison of Rapid Low-Temperature regeneration and Normal Regeneration

rapidlowtemp2.png

Technology

Solution

This website use cookies to obtain and use access data to understand the convenience and usage of customers. If you agree to use cookies, click "I Accept".
[Privacy Plicy] [Cookie Policy]

I Accept