Self-aligned multiple patterning processes with layered mandrels

A method comprising:

• forming a first mandrel line including a first mandrel layer disposed on a hardmask and a second mandrel layer disposed over the first mandrel layer;
• removing a first section of the second mandrel layer to form a mandrel cut that exposes a first section of the first mandrel layer and that is arranged along the first mandrel line between respective second sections of the second mandrel layer;
• masking the first section of the first mandrel layer;
• after masking the first section of the first mandrel layer, removing the second sections of the second mandrel layer with a first etching process to expose the second sections of the first mandrel layer;
• after removing the second sections of the second mandrel layer, removing the second sections of the first mandrel layer to expose first portions of the hardmask;
• and
• removing the first portions of the hardmask with a second etching process to form a first trench,
• wherein a second portion of the hardmask is masked by the first section of the first mandrel layer during the second etching process to form a cut in the first trench in the hardmask.