RF Power Feedthroughs are engineered for the transmission of Radio Frequency (RF) power into vacuum environments. Unlike conventional DC feedthroughs, RF designs use high-conductivity, non-magnetic materials at the ceramic-to-metal interfaces to reduce current induction effects.

A key application is in-vacuum induction heating, with models available up to 35 kW and frequencies of 13.56 MHz. Constructed with copper alloys, these feedthroughs minimize RF coupling, unlike nickel-iron alloys used in standard DC types, which can overheat and fail under RF loads.

To further reduce heating, RF Power Feedthroughs are water-cooled. At high frequencies, the skin effect concentrates current on the conductor’s surface, increasing resistive heating. Water cooling offsets this effect, enabling safe, high-power operation.

Testing of a 35 kW feedthrough determined a minimum coolant flow rate of 4 gallons/hour (15.1 liters/hour). When installing two 35 kW / 13.56 MHz feedthroughs side by side, their center-to-center spacing must exceed 2.00 inches (50.8 mm) to prevent RF coupling.

MDC Precision offers RF Power Feedthroughs in three mounting styles: Weldable, Conflat®-compatible flanges, and ISO NW-compatible Kwik-Flanges™.

Voltage/Current & Power Ratings:
8000 Volts DC (8 kV DC), 10 kW at 450 kHz
10,000 Volts DC (10 kV DC), 20 & 35 kW at 13.56 MHz
Maximum Bakeout Temperature:
Conflat CF: 450°C (842°F)
Kwik-Flange™: 150°C (302°F)
Weldable: 450°C (842°F)
Conductor Tube Material: Copper
Number of Tubes: 1 or 2

Industry Applications

RF Power Feedthroughs are widely used in high-frequency, high-power vacuum applications. Common industries include semiconductor processing, plasma generation, induction heating, nuclear research, and particle accelerators. Their copper construction, water-cooling system, and RF-optimized design ensure safe, reliable power delivery where precision and durability are critical.