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Hi,
I'm working with a piece of kit which is used to accelerate ions in the manufacturing of silicon chips. We generate 350KeV using a high frequency power supply and a high voltage stack, basically a Cockcroft Walton Voltage Multiplier.
Bit of advice I'm looking for is based on the fact that the high voltage discharges to the ceiling of the enclosure when raised above 315KeV. The power supply, although rated to 350KeV, is only 0.5mA rated.
I'll try to explain using the photograph.
https://www.youtube.com/watch?v=svQbKYvqMk4
you tube search for HT400-10DE finds the video / photograph
The red terminal above is approc 1.4m long, the main box section sits on the red insulators. From red terminal to floor (ground) is 74cm, from red terminal to side walls is 73cm, but red terminal to the ceiling (the ciling is grounded) is 65cm. We see discharge to the ceiling. So, may sound obvious that the ceiling is just too low, but can anyone justify with data to show that 350KeV and 65cm just don't match ? Or do they match ?
In addition to the ceiling gap being so small, I have 1 other thought. I've read about the bloke called Friedrich Paschen, whose Law (curve) proves the relationsip between HV breakdown and pressure. From the top of the red box to the ceiling of the roof, there is an extract pulling 2.9m/s which is required to extract toxic gas fumes.
My thoughts are "to raise the roof" (ceiling really) but I'd be greatful of any technical data that would justify my expense of doing so.
For interest, I have a youtube video of the high voltage discharge which you are free to watch and comment on.
I'm working with a piece of kit which is used to accelerate ions in the manufacturing of silicon chips. We generate 350KeV using a high frequency power supply and a high voltage stack, basically a Cockcroft Walton Voltage Multiplier.
Bit of advice I'm looking for is based on the fact that the high voltage discharges to the ceiling of the enclosure when raised above 315KeV. The power supply, although rated to 350KeV, is only 0.5mA rated.
I'll try to explain using the photograph.
https://www.youtube.com/watch?v=svQbKYvqMk4
you tube search for HT400-10DE finds the video / photograph
The red terminal above is approc 1.4m long, the main box section sits on the red insulators. From red terminal to floor (ground) is 74cm, from red terminal to side walls is 73cm, but red terminal to the ceiling (the ciling is grounded) is 65cm. We see discharge to the ceiling. So, may sound obvious that the ceiling is just too low, but can anyone justify with data to show that 350KeV and 65cm just don't match ? Or do they match ?
In addition to the ceiling gap being so small, I have 1 other thought. I've read about the bloke called Friedrich Paschen, whose Law (curve) proves the relationsip between HV breakdown and pressure. From the top of the red box to the ceiling of the roof, there is an extract pulling 2.9m/s which is required to extract toxic gas fumes.
My thoughts are "to raise the roof" (ceiling really) but I'd be greatful of any technical data that would justify my expense of doing so.
For interest, I have a youtube video of the high voltage discharge which you are free to watch and comment on.