A fluidized bed reactor with one or more stages each stage having a heating
section located below a reacting section and a mechanism that pulses
granules back and forth between the heating and reacting sections,
separate injectors for silicon containing gases non silicon containing
gases, heaters to heat the non silicon containing gases above the reaction
temperature and the silicon containing gases to a temperature just below
their decomposition temperature. The heater for the silicon containing
gases controls the condensing vapor of a heat transfer fluid to a
temperature below the decomposition temperature of the silicon containing
gases. An enclosed noncontaminating sieving device selectively removes
product and recycles undersize material. A weigh cell with frequency
analysis capability provides information on the weight of the reactor and
the force exerted by the pulsing action of the granules.
