Method of forming integrated circuit features by oxidation of titanium hard mask

A method of manufacturing an integrated circuit comprising:

• depositing a photoresist material over a layer of titanium deposited over an inter-level dielectric (ILD) layer;
• etching the photoresist material to form photoresist features having a first separation distance from each other;
• etching the layer of titanium using the photoresist features as a mask to form titanium features;
• and
• oxidizing the titanium features such that the titanium features expand and are separated from each other by a second separation distance, the second separation distance being less than the first separation distance.

A method of forming integrated circuit device features, the method comprising:

• patterning an oxidizable layer using a resist layer to form at least two oxidizable features;
• oxidizing the at least two oxidizable features, the at least two oxidizable features including a material that expands during oxidation, wherein a distance between the at least two oxidizable features decreases due to expansion of the at least two oxidizable features during oxidation;
• and
• patterning a layer under the at least two oxidizable features to form a feature, the feature having a critical dimension substantially equivalent to the distance between,the at least two oxidizable features.