(HI)20N50 datasheet? It should be a MOSFET ...

Hello, i am looking for datasheet, or any closer information about

HI20N50FI part. It has ST manufacturer logo, altough no information can be found on st online pages.

I suggest, could the Phillips PHW20N50 be a substite ..

Please help, i have to replace that part in a industrial power supply which is 1991 age and have no schematics for it at all...

Regards,

M. Janosek