In high vacuum and UHV conditions, high voltage electrical feedthroughs are used widely. This use of high voltage electrical feedthroughs enables the transmission of high voltages both into and out of hermetically sealed chambers, without reaching a point of potential pressure loss, thanks to the ingress of atmospheric gases.
In this article, the available high voltage feedthroughs available from Allectra, as well as their significance and uses, are outlined in more detail.
Significance of High Voltage Feedthroughs
High vacuum conditions range from approximately 10-5 millibar (mbar) – 10-9 mbar. To achieve this pressure regime, it is necessary to evacuate a chamber to all but residual gaseous molecules. A series of pumps is required to effectively evacuate the chamber, given that collisions between these molecules and the walls of the vacuum chamber dominate the pressure regime.
To exhaust the bulk of the gases, a rough vacuum pump is used. At the onset of the high vacuum regime, however, a different pump is necessary to evacuate residual molecules, once they have entered the pump aperture.
The conditions of an ultra-high vacuum (UHV) are even more severe than the above and extend in almost entirely dry conditions above 10-9 mbar. This range of pressure is on an order of trillionths of the atmosphere. It is primarily hydrogen (H2) that remains in UHV conditions while water molecules persist in high vacuum processes, thanks to the lightness of the gas and the high mobility.
To achieve high purity vacuum conditions of greater than 10-9 mbar, specialist UHV pumps and bakeout are required.
The backing of multiple pumps and hermetically sealed processing chambers is necessary to achieve the high vacuum and UHV conditions, as it is an energy-intensive process. Voltage feedthroughs are required to alter process conditions in real-time without compromising the vacuum’s integrity,
Depending on the application requirements and chamber architecture, the designs of high voltage feedthroughs can vary significantly.
Allectra can provide a huge variety of voltage feedthroughs for high vacuum and UHV processing, including:
- Coaxial, Safe High Voltage (SHV) Feedthroughs, which have the option of either recessed or exposed ceramic on the vacuum side and a choice of either 5/6 kilovolt (KV) signals. The SVH10 is rated for 10 KV, and the SHV20 is rated for 20 KV.
- MIL-C-5015-compliant MS Circular Socket high voltage feedthroughs with multiway pins, offered with either 7.5, 10, 23, or 40A per pin.
- Power Glove high voltage feedthroughs, which have sockets and air-side cables. There are numerous design options available for our Power Glove feedthroughs, with voltage capacities of 5, 10, 20, and 40 KV. Options for multiple pins and various flange types are available, which additionally ameliorate the applicability of the product.
This information has been sourced, reviewed and adapted from materials provided by Allectra Limited.
For more information on this source, please visit Allectra Limited.