Apparatus for heat treating semiconductor wafers

摘要

Method of heat treating semiconductor wafers in a continuous operation wherein the wafers are initially introduced into a tube where they are subjected to a heat treatment and then removed from the tube. The wafers are transported through the tube by a pair of horizontally disposed rods on which they are carried and by an additional guide rod which is located above the horizontal plane of the first rods. All three rods have a groove in the form of a screw thread into which the wafers may be seated. All three rods are caused to rotate in the same direction and the frictional contact of the wafers with the walls of each groove causes the wafers to rotate in the opposite direction from the rods while at the same time causing them to advance through the tube while being heated. If it is desired to have the entry speed and the exit speed to be faster or slower than that through the main body of the tube, the pitch of the screw thread may be increased or decreased, respectively, at the entrance and exit of the tube. The rods are preferably made of the same semiconductor material as the wafers.