Methods of T-gate fabrication using a hybrid resist

A method of forming a T-gate on a substrate comprising:

• providing a substrate layer;
• depositing an etch-stop layer over the substrate layer;
• depositing a cap layer over the etch stop layer;
• depositing a metallization layer over the cap layer;
• patterning the metallization layer to form source and drain regions thereby exposing a portion of the cap layer;
• conformally depositing a silicon nitride layer over the source and drain regions, and over the exposed portion of the cap layer;
• depositing a first hybrid resist layer on silicon nitride layer;
• positioning a first mask having a reticle feature with an edge above the first hybrid resist layer so that the edge of the reticle feature is above a desired location for a base of the T-gate;
• exposing only the portion of the first hybrid resist layer underlying the edge of the reticle to radiation through the mask;
• developing the exposed portion of the first hybrid resist layer whereby the exposed portion of the first hybrid resist layer is washed away by a developing solution to define an opening therein the first hybrid resist layer used to form the base of the T-gate, the opening having a loop feature formed in the first hybrid resist layer having a pattern consistent with the edge of the reticle;
• trimming the loop feature formed in the first hybrid resist layer to prevent shorting the T-gate;
• and
• forming the T-gate within a location of the trimmed loop feature formed in the first hybrid resist layer.