| 摘要 |
<p>A first impurity region (123) is formed by ion implantation through a first opening formed in a mask layer (31). By depositing a spacer layer (32) on an etching stop layer on which the mask layer (31) has been provided, a mask portion (30) having the mask layer (31) and the spacer layer (32) is formed. By anisotropically etching the spacer layer (32), a second opening (P2) surrounded by a second sidewall is formed in the mask portion (30). A second impurity region (124) is formed by ion implantation through the second opening (P2). An angle (AW) of the second sidewall with respect to a surface (SO) is 90°±10° across a height (HT) as great as a second depth (D2). Thus, accuracy in extension of an impurity region can be enhanced.</p> |
