Patterning interconnects and other structures by photo-sensitizing method

A method comprising:

• providing a substrate;
• forming a first and a second etch stop layer over the substrate;
• depositing a photo-sensitive layer over the second etch stop layer;
• blanket depositing cap layers over the photo-sensitive layer, the cap layers being transparent to a pre-selected wavelength of light;
• patterning the cap layers to form an opening therein;
• filling the opening with a plug;
• exposing the photo-sensitive layer to light energy of the pre-selected wavelength through the cap layers to convert exposed portions of the photo-sensitive layer to conductive regions;
• and removing unexposed portions of the photo-sensitive layer to form trenches;
• and
• filling the trenches with a material.

A method comprising:

• depositing a photo-sensitive layer over a substrate, the substrate including an etch stop layer formed thereon;
• forming a patterned mask layer over the photo-sensitive layer, the patterned mask layer masking portions of the photo-sensitive layer while leaving second portions of the photo-sensitive layer un-masked;
• exposing the un-masked portions of the photo-sensitive layer to a light of a pre-selected wavelength, wherein the exposure changes an electrical conductivity characteristic of the un-masked portions, or a resistance to a pre-selected etch process of the un-masked portions;
• when the exposure changes the electrical conductivity of the un-masked portions, forming an insulator electrically isolating adjacent un-masked portions;
• and
• when the exposure changes the resistance to the pre-selected etch process of the un-masked portions, etching the un-masked portions to form an opening, and filling the opening with a conductive material.