| 摘要 |
PURPOSE:To provide a high concentration layer to a substrate having a large diameter effectively by applying a liquid solution including a dopant for a semiconductor substrate to a desired thickness directly, heating it and preparing a diffusion layer. CONSTITUTION:An impure undiluted solution is dropped onto a semiconductor substrate and coats it while rotating. An impurity concentration in a coating film and film thickness for forming are prescribed. Then, when these plates are separately arranged from one another and performed the heat diffusion in a heating furnace, the seat resistance thereof becomes uniform. In this case, the undiluted solution of impurity is controlled to within a range of 16-49.5wt% of the concentration and of 0.7-1.5mu of a film thickness of rotation coating with an alcohol solution including P2O5. As the result of this method, the variation of a sheet resistance is decreased and the diffusion of the impurity can be performed with good controlling. |
