High purity diffusion, annealing and oxidation
The diffusion furnace HTF is equipped with up to 4 individually controllable tubes. The loading and unloading of boats in the tubes is done automatically by loading units. One boat is loaded into a tube per cycle. A boat can be filled with 500 wafers with back-to-back loading. After the drive-in and the heat-up step, the process starts with a temperature stabilization. After that, nitrogen is used as carrier gas for the POCl3 liquid. An additional oxidation steps follows to finish the process. After the set time the diffusion tube is opened for subsequent unloading.