Deep well implant using blocking mask

A method comprising:

• providing a precursor structure having:
• a substrate;
• an etch stop layer over the substrate;
• a blocking layer, including tungsten (W), over the etch stop layer;
• and
• a resist layer over the blocking layer;
• forming an opening in the resist layer to expose the blocking layer;
• etching the blocking layer to expose a portion of the etch stop layer, wherein the etch stop layer resists etching during the etching of the blocking layer;
• etching the exposed portion of the etch stop layer to expose a portion of the substrate below the exposed portion of the etch stop layer and leave a remaining portion of the etch stop layer;
• ion implanting the exposed portion of the substrate, wherein the blocking layer prevents ion implanting of the substrate outside of the exposed portion of the substrate,
• wherein the ion implanting includes implanting ions to a depth of approximately 600 nanometers (nm) to approximately 50 nm in the substrate, and wherein the blocking layer has a thickness of approximately 50 nm to approximately 400 nm;
• and
• stripping the blocking layer and the etch stop layer after the ion implanting.

A method comprising:

• providing a precursor structure having:
• a substrate;
• an etch stop layer including zirconium anti-reflective coating (ZrARC) over the substrate;
• a blocking layer, including tungsten (W), over the etch stop layer;
• and
• a resist layer over the blocking layer;
• forming an opening in the resist layer to expose a portion of the blocking layer;
• performing a reactive ion etch (RIE) on the exposed portion of the blocking layer to expose a portion of the etch stop layer below the exposed portion of the blocking layer, wherein the etch stop layer resists etching during the RIE;
• etching the exposed portion of the etch stop layer below the opening within the blocking layer to expose a portion of the substrate and leave a remaining portion of the etch stop layer;
• and
• ion implanting the exposed portion of the substrate, wherein the blocking layer prevents ion implanting of the substrate outside of the exposed portion,
• wherein the ion implanting includes implanting ions to a depth of approximately 500 nm nanometers in the exposed portion of the substrate, and wherein the blocking layer has a thickness of approximately 100 nm nanometers,
• wherein the ion implanting includes implanting ions into the blocking layer, wherein the ion implanting of the blocking layer includes ion implanting to a depth of approximately 60 nm to approximately 5 nm.