摘要 |
A method for estimating molecular nitrogen implantation dosage. The semiconductor wafers are first implanted with various concentration of molecular nitrogen. After implantation, the implanted wafers and a non-implanted wafer are subjected to thermal process to grow oxide layer. The thickness of oxide layer on the wafers with various implantation dosage is measured. Because implanted nitrogen on the wafers suppresses the growth of oxide layer, a suppression ratio is computed from the difference in thickness of the oxide layer between the implanted and non-implanted semiconductor wafers to stand for the thickness variation. Then, a relation between the suppression ratio and the dosages of molecular nitrogen is built. A molecular nitrogen dosage needed to grow a predetermined thickness of oxide layer on a process wafer is computed by inputting the predetermined thickness into the relation.
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