Inhibition of fluid flow instabilities in the melt by the axial magnetic field in Czochralski silicon crystal growth (AMCZ) is investigated precisely by a high‐sensitivity striation etch in conjunction with temperature measurements. The magnetic field strength (B) was varied up to 4.0 kG, incremented mostly in 0.5‐kG/2.5‐cm crystal length. The convection flow was substantially suppressed atB≥1.0 kG. A low oxygen level of 2–3 ppm and a high resistivity of 400 &OHgr; cm is achieved in the AMCZ silicon crystals atB≥1.0 kG. Random striations atB=0, characteristic of turbulent convection, assumed progressively a periodicity, indicative of oscillatory convection at 0.35<B≤4.0 kG. The striation contrast or ‘‘intensity’’ decreased steadily with the increase inB. AtB=4 kG, most of the crystal was free of striations, although some weak, localized periodic striations persisted near the crystal periphery. Spreading‐resistance measurement shows, however, a uniform dopant distribution in all crystal sections grown at 0.35<B≤4.0 kG within a few percent.