144-pin TQFP supplied on cut tape. Die revision B.
Markings (top side):
XILINX(R) SPARTAN(R)-6 XC6SLX4(TM) TQG144BIV1209 D4371643A 2C
Samsung 45nm process.
Passivation was somewhat damaged due to overly aggressive cleaning.
Bond pads and test points
Damaged passivation (from cleaning)
x1 metal layer (probably M5 and M6) in SEM: