A valve for redirecting flow in a supercritical fluid or other high pressure processing system is disclosed. In high pressure supercritical carbon dioxide (SCCO2) equipment for semiconductor wafer processing, a major hurtle in providing clean equipment and clean wafers. A clean flow diverting valve is provided having no grease or other contaminants, and having no rubbing seal surfaces, but rather incorporates a magnetically coupled valve actuator to move a ball or other valve seat for diverting flow between a common port and alternative switched ports in a non-rubbing, non-contact manner. The valve is useful in semiconductor wafer high pressure processing tools for redirecting flow from a common inlet to alternative outlets or for admitting flow from alternative inlets to a common outlet.