Method of forming sub-micron-size structures over a substrate

A method, comprising:

• forming a width-defining step over the substrate, having a longitudinal edge extending lengthwise over the substrate;
• forming a width-defining layer over the width-defining step, down the longitudinal edge thereof and over the substrate;
• etching the width-defining layer back to leave a sub-micron-size spacer adjacent the width-defining step, the spacer extending along the longitudinal edge, and having a first width-defining edge adjacent the step, and a second, opposing width-defining edge distant from the longitudinal edge, a sub-micron-size width of an area being defined between the first and second width-defining edges;
• forming a length-defining step over the substrate, having a transverse edge extending across the width over the substrate;
• forming a length-defining layer over the length-defining step, down the transverse edge thereof and over the substrate;
• and
• etching the length-defining layer back to leave a spacer adjacent the length-defining step, the spacer extending along the transverse edge, and having a first length-defining edge adjacent the step, and a second, opposing length-defining edge distant from the longitudinal edge, a sub-micron-size length of the area being defined between the first and second length-defining edges.

A method of forming a sub-micron-size structure over a substrate, comprising:

• forming a width-defining step over the substrate, having a longitudinal edge extending lengthwise over the substrate;
• forming a width-defining layer over the width-defining step, down the longitudinal edge thereof and over the substrate;
• etching the width-defining layer back to leave a sub-micron-size spacer adjacent the width-defining step, the spacer extending along the longitudinal edge, and having a first width-defining edge adjacent the step, and a second, opposing width-defining edge distant from the longitudinal edge;
• forming a length-defining step over the substrate, having a transverse edge extending across the spacer left by the width-defining layer;
• forming a length-defining layer over the length-defining step, down the transverse edge thereof and over the substrate;
• etching the length-defining layer back to leave a spacer adjacent the length-defining step and across the spacer left by the width-defining layer, the spacer extending along the transverse edge, and having a first length-defining edge adjacent the step, and a second, opposing length-defining edge distant from the longitudinal edge;
• and
• etching the spacer left by the width-defining layer with the spacer left by the length-defining layer serving as a mask, to form the structure.