high frequency D flip flop for phase detector

Hello, i have succeeded to implement a phase detector using modification of xor logic circuit. how ever the more popular implementation is using D FLIP FLOP shown bellow.

I have read many articles  explaining the principle and i understand it well, but the simulation always goes bad.

is there some example in the cadence website of D flip flops full simulation? not necessary 5Ghz  ,some thing modest i could learn from?

Thank