And oh look: I just noticed that the Cree SiC device has an internal 26 Ohm gate resistance already. Gate resistance that high is not inherent in SiC technology; they added some resistance to the device inside the package. I'll give you one guess as to why they did that. This reinforces my point. Adding more externally would help protect (given the caveats above) but obviously the need is reduced in this case. I still don't like the idea of blowing up the internal gate resistor and wrecking the whole device when I could have done something about it.
I don't think this is quite true. The gate resistance is usually caused by the lossy-ness of the semiconductor material and the very fine binding wires used to connect the die to the outside world. You'll notice on most datasheets this is derived by measuring the AC resistance of the junction at a known frequency and amplitude. The larger the die and its gate structure, the larger the parasitic gate capacity, and the higher the gate AC resistance. This is dependent on which silicon technology and topology is being used, obviously.
I can't speak with any authority on other technologies, but the metalization of the gate structure in SiC is one of the reasons for the higher gate resistance than comparable Si devices.
+-RH
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