A furnace tube device comprises a base and a shell, a furnace tube cavity for containing wafers is defined by the base and the shell, multiple trays used for containing the wafers is formed in the surface, facing the furnace tube cavity, of the base. The multiple trays are arranged on the base, the wafers can be placed on the trays in a dispersed manner, and therefore the height of the furnace tube cavity can be reduced. When the height of the furnace tube cavity is reduced, it means that the distance between the wafers at the two ends in the height direction is reduced, the process conditionsof the wafers are close, each wafer has the quite close treatment effect, and the product yield is improved.