We have acquired high stable、high dependable、low etch channel density quartz crystals through the sweeping technique in this work. The sweeping process can reduce Na+ impurities from 2.33×10-6 to 0.3×10-6,reduce etch channel density from ≤100/cm2 to ≤10/cm2.By using the proposed sweeping process , the quartz crystals with etch channel density≤3/cm2 have been prepared,and the anti radiation excellent has been improved by 2 order of magnitudes.