Method for manufacturing semiconductor device

A manufacturing method of a semiconductor device includes: forming a second conductive type layer (6, 41, 51) over a first conductive type layer (5, 40, 50); and forming a trench (11, 43, 53) by etching the second conductivity type layer by a plasma etching process to expose the first conductivity type layer. The etching of the second conductivity type layer includes: performing a spectroscopic analysis of light emission of plasma; detecting an interface between the first conductivity type layer and the second conductivity type layer based on a change in emission intensity; and stopping the etching of the second conductivity type layer when an end point is determined based on a detection result of the interface. 一种半导体器件的制造方法包括：在第一导电类型层(5、40、50)上方形成第二导电类型层(6、41、51)；以及通过借助于等离子体蚀刻工艺蚀刻所述第二导电类型层以露出第一导电类型层而形成沟槽(11、43、53)。第二导电类型层的蚀刻包括：对等离子体的光发射执行光谱分析；基于发射强度的变化检测第一导电类型层和第二导电类型层之间的界面；以及在基于界面的检测结果确定终结点时，停止对第二导电类型层的蚀刻。