| 摘要 |
PURPOSE:To form a thin impurity region on the surface of a substrate by a method wherein impurity is ion-implanted into the surface of a semiconductor substrate, the impurity is activated to form an impurity region on the surface of the substrate with heat-treatment, and this impurity region is etched. CONSTITUTION:The surface of a semiconductor substrate 1 is implanted the impurity ion 2 producing reverse conduction type in relation to the semiconductor substrate 1 so as to form an impurity region 31 with depth of junction Xj1. Then, annealing is performed to form a impurity region 32 with depth of junction Xj2 by activating the implanted impurity. Then, the surface of the semiconductor substrate 1 is removed by etching it by desired depth with reactive ion-etching method to control the depth of junction of the impurity region 32 to the depth Xj3. Thus, a very thin junction P-N junction of about 0.1mum is realized on the semiconductor substrate, thereby providing a contact with favorable impurity density on the surface of the semiconductor substrate. |
