Process for forming a conductive region without photoresist-related reflective notching damage

A process for forming a region of semiconductive material comprising the steps of:

• providing a silicon substrate;
• forming a semiconductive layer overlying the substrate, the semiconductive layer having a surface and having a native oxide formed on said surface;
• forming a photoresist mask layer overlying the semiconductive layer;
• forming openings in the photoresist mask layer which expose portions of the semiconductive layer, the openings forming sidewalls of the photoresist mask layer;
• etching the native oxide on the surface of the semiconductive layer which is exposed by the openings in the photoresist mask layer;
• forming a polymer coating on said sidewalls of the photoresist mask layer by exposing the photoresist mask layer to an ion bombardment environment, the polymer coating atomically consisting of repeating structural units;
• and
• etching the portions of the semiconductive layer which are exposed by the openings in the photoresist mask layer to form said region of semiconductive material.

A process for forming a region of polysilicon comprising the steps of:

• providing a silicon substrate;
• forming a polysilicon layer overlying the silicon substrate, the polysilicon layer having a surface and having a native oxide formed on said surface;
• forming a photoresist mask layer overlying the polysilicon layer;
• forming openings in the photoresist mask layer which expose portions of the polysilicon layer, the openings forming sidewalls of the photoresist mask layer and defining at least one reflective notch in the photoresist mask layer;
• etching the native oxide on the surface of the polysilicon layer which is exposed by the openings in the conductive layer;
• forming a hardened polymer coating on said sidewalls of the photoresist mask layer by exposing the photoresist mask layer to an ion bombardment environment, wherein the hardened polymer coating is more resistant to removal than the photoresist mask layer;
• etching the portions of the polysilicon layer which are exposed by the openings in the photoresist mask layer in an ambient having a first chemical composition;
• and
• over-etching portions of the polysilicon layer in an ambient having a second chemical composition to form said region of polysilicon and preventing the reflective notch from being transferred into the region of polysilicon due to the presence of the hardened polymer coating on the photoresist mask layer.

A method for forming a semiconductor structure, the method comprising the steps of:

• providing a substrate material;
• forming a conductive layer overlying the substrate material;
• forming a masking layer over the conductive layer;
• patterning the masking layer to expose a portion of the conductive layer to form exposed potions of the conductive layer and form sidewalls of the masking layer;
• exposing the masking layer to a gas-containing environment wherein atoms are ion bombarded onto the surface of the masking layer, the step of exposing forming a hardened sidewall layer by consuming a sidewall portion of the masking layer, the hardened sidewall layer being more resistant to removal than the masking layer when exposed to a removal chemistry;
• and
• removing the exposed portions of the conductive layer selective to the hardened sidewall layer.

A method for forming a semiconductor structure, the method comprising the steps of:

• providing a substrate material;
• forming a conductive layer overlying the substrate material;
• forming a masking layer over the conductive layer;
• patterning the masking layer to expose a portion of the conductive layer to form exposed potions of the conductive layer and form sidewalls and a top surface of the masking layer;
• exposing the sidewalls of the masking layer to a gas-containing ion bombardment environment wherein the ion bombardment allows a hardened layer of material to be formed only adjacent the sidewalls of the masking layer by bombarding material off the top surface of the masking layer, the hardened layer of material consuming a sidewall portion of the masking layer;
• and
• etching the exposed portions of the conductive layer selective to the hardened layer of material.