It goes wherever the exhaust of the pump goes, of course. If you don't have an exhaust tube attached to it, you're filling your lab with exhaust gas (which would be illegal at least here in Germany due to safety regulations, I believe). Otherwise it goes wherever your exhaust tube goes.

Dr Tuhmaz,

I think that my answer to this exact same question last month is still appropriate;

From March 28th:

"Dr Tuhmaz,

It goes to wherever your vacuum pump exhausts to.

In most cases, that is the atmosphere (via an oil mist-trap: if on a rotary 'roughing' pump). Simply follow the line from the last pump's exhaust.

Ah: a sputtering chamber - well, that's a relatively poor vacuum (depending on the size of that chamber - but in any case the argon probably vents to the laboratory via a filter or two. It would be hard, but not impossible, to sequester it."

A related question is, where should it vent to.

And the proper answer is, as Dr Weippert wrote, "outside".

Hello everyone,

Look, Let us start with you vacuum pump (Rotary or diffusion as example). As, you connect it to the sputtering chamber, and before allowing the Ar gas to flow, at this moment, the pump draws or sweeps, the air out from the chamber. The air goes through the pump cycle, then to the exhaust exit.

Then, when you allows the Ar gas to flow, it will fill the same volume of the air, some will be used for sputtering, and as a whole, it will be also drawn out via the pump, then to the exhaust exit.

So, yes, I agree with James Garry and Jürgen Weippert , the Ar gas will finally, pulled out to you lab atmosphere.

Regards.