| 摘要 |
PROBLEM TO BE SOLVED: To effectively getter a contaminated heavy metal at relatively low temperatures and prevent a rediffusion to a device active layer of a contaminated heavy metal element which is gettered. SOLUTION: A contaminated heavy metal element (Fe) 10 is mixed during the step of manufacturing a semiconductor device and is assumed to exist near a p-n junction. First, P ions are implanted with the use of an oxide film 7 as a through film (a). Next, the contaminated heavy metal element 10 is gettered to a silicon oxide film 7 by an activation heating treatment of implanted ions (b). A heating treatment is performed under an atmosphere of HCl+O2, to form a chloride (FeCl2) of a contaminated heavy metal, to remove this out of a wafer. The oxide film 7 is removed with HF vapor or H2 (c). Thereafter, a doped polysilicon 9 which comes in contact with an n-type diffused layer 5 is formed (d). |
