Method for forming barrier layer and method for manufacturing semiconductor device

A method for manufacturing a semiconductor device, comprising:

• a step (A) of forming a base layer having a three-dimensional structure;
• a step (B) of forming a barrier layer on the base layer;
• a step (C) of forming a dopant-containing layer on the barrier layer by using an atomic layer deposition (ALD) process;
• and
• a step (D) of performing a heat treatment,
• wherein in the step (B), at least one of a film thickness, a film quality, and a film type of the barrier layer is controlled in a height direction of the three-dimensional structure by using the atomic layer deposition process, and
• in the step (D), a dopant contained in the dopant-containing layer is diffused into the base layer through the barrier layer,
• wherein in the step (C), a concentration of the dopant in the dopant-containing layer is decreased along a direction from an upper region to a lower region of the three-dimensional structure.