Generation of multiline etch substrates

A method of microfabrication comprising:

• providing a first relief pattern on a target layer, wherein the first relief pattern comprises a first resist having a first etch selectivity;
• coating the first relief pattern with a solubility-shifting agent;
• depositing a second resist on the first relief pattern such that the second resist is in contact with the first relief pattern, wherein the second resist has a second etch selectivity that is different from the first etch selectivity;
• diffusing the solubility-shifting agent a predetermined distance into the second resist to provide a solubility-shifted region of the second resist, wherein the solubility-shifted region of the second resist borders the first relief pattern;
• developing the second resist such that the solubility-shifted region is dissolved providing gaps between the first relief pattern and the second resist where a portion of the target layer is exposed;
• and
• filling the gaps between the first relief pattern and the second resist with a fill material,
• wherein the method further comprises:
• removing the first relief pattern;
• transferring a pattern defined by the second resist and the fill material into the target layer;
• and
• filling the target layer with a second fill material.