Is there such a thing as an insulated gate SCR or anything fitting that description?
Apparently MOS-controlled thyristors were commercially available briefly, but were withdrawn due to performance issues.
The structure looked like this:
There are several types of SCR.
Standard SCR : turns on at application of gate signal. Stays on in absence of gate signal until anode cathode current falls below threshold current level.
GTO : Gate Turn Off SCR : SCR can be commanded to turn off under certain conditions.
Insulated Gate Bipolar Transistor : IGBT : Stays on while gate signal applied.
Turns off when gate signal is removed (regardless of collector current)
Simple description of each, further search will help based upon key words. .
I don't know of any device available that fits your description