Forming contact holes with controlled local critical dimension uniformity

A method of forming a semiconductor device, the method comprising:

• forming a hole pattern in a resist layer disposed over a substrate, the substrate comprising contact regions disposed over a major surface of the substrate and a dielectric layer disposed over the contact regions, the resist layer being disposed over the dielectric layer, the hole pattern comprising through openings in the resist layer that are aligned with the contact regions;
• modifying the hole pattern by depositing a material comprising silicon within the through openings by exposing the hole pattern to a first plasma generated from a gas mixture comprising SiCl4 and hydrogen;
• and
• measuring critical dimensions of the through openings with the material comprising silicon;
• determining a local critical dimension uniformity value based on the critical dimensions of the through openings with the material comprising silicon;
• generating a set of process parameters by adjusting process parameters of the first plasma based on a difference between the local critical dimension uniformity value and a target local critical dimension uniformity value;
• on further substrates, repeating the steps of forming the hole pattern, modifying the hole pattern with the first plasma using the generated set of process parameters, measuring the critical dimensions of the through openings with the material comprising silicon, determining the local critical dimension uniformity value, generating the set of process parameters until the local critical dimension uniformity value reaches a target local critical dimension uniformity value;
• performing the steps of forming the hole pattern in another substrate and modifying the hole pattern with the first plasma using the generated set of process parameters;
• and
• etching holes in the dielectric layer by exposing the dielectric layer to a second plasma through the modified hole pattern, the holes exposing the contact regions.

A method of forming a semiconductor device, the method comprising:

• forming a hole pattern in a resist layer disposed over a substrate, the substrate comprising contact regions disposed over a major surface of the substrate and a dielectric layer disposed over the contact regions, the resist layer being disposed over the dielectric layer, the hole pattern comprising through openings in the resist layer that are aligned with the contact regions;
• measuring critical dimensions of the through openings;
• determining a local critical dimension uniformity value based on the critical dimensions of the through openings;
• generating a set of process parameters by adjusting process parameters of a first plasma based on a difference between the local critical dimension uniformity value and a target local critical dimension uniformity value;
• modifying the hole pattern by depositing a material comprising silicon within the through openings by exposing the hole pattern to the first plasma generated from a gas mixture comprising SiCl4 and hydrogen and using the generated set of process parameters;
• and
• etching holes in the dielectric layer by exposing the dielectric layer to a second plasma through the modified hole pattern, the holes exposing the contact regions.