Structure and formation method of interconnection structure of semiconductor device

A method for forming a semiconductor device structure, comprising:

• forming a first conductive feature in a first dielectric layer;
• performing a plurality of deposition cycles to form an aluminum nitride layer covering the first conductive feature and the first dielectric layer, wherein each of the plurality of deposition cycles comprises:
• introducing an Al-containing precursor over the first conductive feature and the first dielectric layer to deposit a layer of Al atoms;
• and
• introducing an N-containing precursor over the layer of Al atoms to deposit a layer of N atoms for a first operation time, wherein the aluminum nitride layer has an atomic percentage of N to Al and N;
• introducing an N-containing reactant over the aluminum nitride layer for a second operation time to increase the atomic percentage of N to Al and N after the plurality of deposition cycles, wherein the second operation time is different from the first operation time.

A method for forming a semiconductor device structure, comprising:

• forming a first conductive feature in a first dielectric layer;
• depositing a first layer to cover the first dielectric layer and the first conductive feature, wherein the first layer comprises aluminum (Al) atoms and carbon (C) atoms;
• depositing a nitrogen layer over the first layer to form an etch stop layer made of aluminum nitride in a first chamber, wherein the C atoms in the first layer are partially replaced by nitrogen (N) atoms in the nitrogen layer;
• introducing a reactant to the etch stop layer to form vacancies in the etch stop layer in a second chamber;
• and
• filling the vacancies in the etch stop layer with additional N atoms, wherein the second chamber is different from the first chamber.