Semiconductor device and method of fabricating the same

摘要

Provided is a method of fabricating a semiconductor device, including the following. A first material layer, a second material layer and a mask layer are formed on a substrate. A portion of the second material layer is removed by performing a first etching process with the mask layer as a mask, so as to expose the first material layer and form a first pattern layer and a second pattern layer. A portion of the first material layer is removed by performing a second etching process with the mask layer as a mask, so as to expose a portion of the substrate. A portion of the substrate is removed by performing a third etching process with the mask layer as a mask, so as to form first trenches and second trenches. Sidewalls of the second trenches and a surface of the substrate form at least two different angles.

主权项

1. A fabricating method of a semiconductor device, the fabricating method comprising:
forming a plurality of material layers on a substrate, wherein the material layers comprise different materials; forming a mask layer on the material layers; and forming a first trench and a second trench in the substrate by performing a plurality of etching processes using different etchants with the mask layer as a mask, wherein at least a first angle and a second angle are formed between a sidewall of the second trench and a surface of the substrate, and a third angle and a fourth angle are formed between a sidewall of the first trench and the surface of the substrate, wherein the first angle is an angle between an inner surface of an upper sidewall of the second trench and a first dividing line, the second angle is an angle between an inner surface of a lower sidewall of the second trench and a second dividing line, the third angle is an angle between an inner surface of an upper sidewall of the first trench and the first dividing line, and the fourth angle is an angle between an inner surface of a lower sidewall of the first trench and a third dividing line, and wherein the first dividing line is a line connecting dividing points between an upper portion and a lower portion of the second trench, the second dividing line is a line connecting a bottom of the second trench, and the third dividing line is a line connecting a bottom of the first trench, wherein the first angle, the second angle, the third angle, and the fourth angle satisfy the following formula (1):
Max the third angle−the fourth angle|