I would like to compute the minimum dead time for two power inverters, the first one is based on IGBT and the second one on MOSFET. I noticed that the switching parameters (Tdon, Tr, Tdoff and Tf) are defined as:

- Tdon: 10% of gate voltage to 10% of collector current

- Tr: 10% to 90% of collector current

- Tdoff: 90% of gate voltage to 90% of collector current

- Tf: 90% to 10% of collector current.

for IGBTs, and for MOSFETs as:

- Tdon: 10% of gate voltage to 90% of collector voltage

- Tr: 90% to 10% of collector voltage

- Tdoff: 90% of gate voltage to 10% of collector voltage

- Tf: 10% to 90% of collector voltage.

Why do we use the collector current for one technology, and the collector voltage for the other one? Can I estimate the switching parameters of an IGBT using the collector voltage?

Thanks in advance