| 摘要 |
PURPOSE:To improve the operational efficiency by a method wherein a silicon substrate is immersed in solution of hydro-acid fluoride or acetone into which heavy metallic chloride is melted. CONSTITUTION:A polycrystalline silicon film 6 and a silicon nitride film 7 are successively formed on a semiconductor substrate 1. FIrstly the films 6, 7 on a killer impurity diffused region 8 are selectively removed by photoetching process to form an opening. Secondly the substrate 1 is immersed in solution of hydro-acid fluoride or acetone into which chloride of metal for killer impurity source i.e. either one of Fe, Cu, Pt or Au is melted and then the substrate 1, after dried up, is heat-treated to selectively diffuse killer impurity in the part thereof exposed to the opening. In such a simple operation, the killer impurity can be bonded on multiple silicon substrates within a short time improving the operational efficiency. |
