Anodic Oxide Films for Device Fabrication in Silicon

The preparation of phosphorus doped anodic oxide films on silicon is described. These oxide films can be used as phosphorus diffusion sources during heat treatment. The concentration and distribution of the phosphorus in the oxide film has been investigated by tracer techniques, the quality of the oxide film by electron microscopy. Oxide growth in the solutions and at the current densities investigated occurs preponderantly by cation migration. A novel method is described for measuring the amount of silicon converted into oxide per volt forming voltage. The density of the oxide can also be calculated by this method.