I'm working on a 13.56 MHz class E amplifier project.
I'm using a EL7158 mosfet driver and IRF610 mosfet as a switch.

To test the EL7158 driver, I first placed a capacitor of 900pF (in the range of the total gate capacitance of the IRF610 switch) at the output, to see if it can charge and discharge the cap fast enough. Results are OK, only a small ripple on the waveform.

Then I connected the EL7158 driver to the switch. When the supply of the class E amplifier, connected to the drain of the switch (with a 150uH inductor), is closed, I get a decent waveform at the gate of the switch. But when I open the current of the supply, the gate voltage gets heavily distorted.. strong ripple on the gate voltage, it becomes unusable. I measured across the ground track, and there is noise of almost equal magnitude across the ground.

I'm not using a ground plane at the moment, just one ground track. Would the use of a ground plane help enough to remove that noise on the gate voltage?
Should I be worried about sparks in the circuit when using a ground plane? I expect around 350V across the series capacitance of the class E amplifier.

thank you