SOi - Is Back-Gate Contact the same as Body-Contact

[x00004785]

Hi,

I have a question regarding SOI devices, is the back-gate contact the same as the body-contact? If not, could someone please explain what the difference is between the two?

Many Thanks,

C

 

[dick_freebird]

No.

Body contact on a NMOS FET will be a P+ plug into
the P- body, from the frontside. Where all the contacts
are.

Back gate is the "handle" wafer below the BOX layer.
A deep contact that penetrates the BOX, and makes
ohmic contact to the handle, is needed. That, or you
just use the die-attach and down-bond to pick that
up. I'm not aware of anyone doing a patterned-doping
handle so your back gate is most likely a common node
which you will bias at whatever potential gives you
the best compromise for device nonideal behaviors.