With advanced manufacturing technology, it is getting difficult to have zero or almost zero-skew clock distribution, even the clock is synthesized to be zero-skew from conventional algorithms. In thiswork, we proposed a practical problem in clock construction with process variation awareness, which is to achieve the balance of the wirelength in preferred direction metal routing. Experimental results show that our approach (unbuffered and buffered clock tree syntheses) performs better than conventional DME algorithms in reducing the skew of the clock.