If you are only generating a pulse every 50ms then you don't necessarily need such a fast rise and fall time since, even with a slower transition time, the average power would still be small.
200mA of drive current from a bipolar 555 will switch the IGBT in 48nC / 200mA = 240ns, which should give fairly low average dissipation in the IGBT.
If you post the load current and voltage I can make an estimate of the power dissipation under those conditions.

 

No, we're not mind readers. No one can confirm your requirements until you state your problem more clearly. Are you using a CMOS 555? Is there some reason why you can't use a regular 555? Regardless of which type of timer you're using, all you need is a voltage high enough to turn on the NPN transistor. .

Actually; the OP stated an IGBT which from the input looks just like a MOSFET - the IGBT is effectively a hybrid Sziklai pair with a PNP emitter follower connected to the drain of an N-channel MOSFET.

 

Actually; the OP stated an IGBT which from the input looks just like a MOSFET - the IGBT is effectively a hybrid Sziklai pair with a PNP emitter follower connected to the drain of an N-channel MOSFET.

The OP hasn't stated why he can't just drive the transistor from the timer output. It should be able to provide enough base drive to saturate the transistor. If not he can use a darlington. If he just wants to learn how the IGBT works, he should ask that.