Fin cutting process for manufacturing finfet semiconductor devices

A method, comprising:

• forming an original fin-formation etch mask above a semiconductor substrate, said original fin-formation etch mask layer comprising a plurality of original line-type features, said original line-type features having a first lateral width that is less than a target lateral width at an upper surface of a plurality of fins to be formed in said substrate;
• removing at least a portion of at least one of said plurality of original line-type features so as to thereby define a modified fin-formation etch mask comprising remaining portions of said plurality of original line-type features;
• performing at least one process operation to add a material to sidewalls of said remaining portions of said plurality of original line-type features of said modified fin-formation etch mask so as to form a plurality of modified line-type features having a second lateral width that is greater than said first lateral width and to expose portions of said substrate;
• and
• after forming said plurality of modified line-type features, performing a substrate etching process through said plurality of modified line-type features to remove at least said exposed portions of said substrate and thereby define a plurality of fin-formation trenches in said substrate that initially define said plurality of fins in said substrate.

A method, comprising:

• forming an original fin-formation etch mask above a semiconductor substrate, said original fin-formation etch mask layer comprising a plurality of original line-type features, said original line-type features having a first lateral width that is less than a target lateral width at an upper surface of a plurality of fins to be formed in said substrate;
• forming a patterned etch mask above said original fin-formation etch mask layer, said patterned etch mask comprising an opening that exposes at least a portion of at least one of said plurality of original line-type features;
• performing a first etching process through said opening in said patterned etch mask to remove said exposed portion of at least one of said plurality of original line-type features so as to thereby define a modified fin-formation etch mask comprising remaining portions of said plurality of original line-type features;
• depositing a conformal layer of material on and in contact with said plurality of remaining portions of said plurality of original line-type features of said modified fin-formation etch mask;
• performing a second anisotropic etching process on said conformal layer such that portions of said conformal layer of material remain positioned adjacent sidewalls of said plurality of original line-type features of said modified fin-formation etch mask after said second anisotropic etching process is completed so as to form a plurality of modified line-type features having a second lateral width that is greater than said first lateral width and to expose portions of said substrate;
• and
• after performing said second anisotropic etching process, performing a substrate anisotropic etching process through said plurality of modified line-type features to remove at least said exposed portions of said substrate and thereby define a plurality of fin-formation trenches in said substrate that initially define said plurality of fins in said substrate.