What that besides a transistor?

[CQCQ]

What this besides a transistor? I see it in many MMIC layout ,but I dont know what that.
-CQCQ

 

[edaedaeda]

probably a heatsink

eda

 

[flatulent]

From its connection to the transistor I would guess ground contacts. However, these 'wings" are too large for ground contacts.

 

[biff44]

It is a FET, and those are the two Drain connections. Under the pads are ground connections to the backside of the chip.

 

[kspalla]

Those are drain vias.

 

[Aya2002]

I think Drain