Method of line roughness improvement by plasma selective deposition

A method for processing a substrate, comprising:

• providing the substrate with at least one underlying layer;
• providing the substrate with a patterned extreme ultraviolet (EUV) photoresist layer overlying the at least one underlying layer;
• performing a cure process to harden the patterned EUV photoresist layer, the cure process including depositing a first layer of additional material on the patterned EUV photoresist layer;
• depositing a second layer of additional material on the substrate, the second layer of additional material selectively deposited, based on the first layer of additional material deposited during the cure process, on the first layer of additional material and above a top surface of the patterned EUV photoresist layer such that a first thickness of the second layer of additional material above the top surface of the patterned EUV photoresist layer is larger than a second thickness of the second layer of additional material on areas of the at least one underlying layer not coated with the patterned EUV photoresist layer, the second thickness being greater than zero;
• and
• utilizing the patterned EUV photoresist layer, the first layer of additional material, and the second layer of additional material as an etch mask and transferring a pattern of the photoresist layer to the at least one underlying layer with the etch mask,
• wherein the first and second layers of additional material each include silicon, and the first layer of additional material is a different silicon containing material than the second layer of additional material, and wherein a thickness of the first layer of additional material is different from a thickness of the second layer of additional material prior to utilizing the etch mask and transferring of the pattern.

A method for processing a substrate, comprising:

• providing the substrate with at least one underlying layer;
• providing the substrate with a patterned photoresist layer overlying the at least one underlying layer, the patterned photoresist layer providing patterned areas of the substrate and unpatterned areas of the substrate, the unpatterned areas of the substrate located between side surfaces of the patterned areas;
• performing a cure process on the photoresist layer using a dichlorosilane gas;
• the method further including depositing an additional material on the substrate, the additional material selectively deposited thicker on a top surface of each patterned area of the photoresist layer than on the unpatterned areas of the substrate, the additional material on the top surface of each patterned area having a first thickness, the additional material on the unpatterned areas having a second thickness that is less than the first thickness, the second thickness being greater than zero;
• and
• utilizing the patterned photoresist layer and the additional material as an etch mask and transferring a pattern of the photoresist layer to the at least one underlying layer,
• wherein the depositing of the additional material includes:
• (a) depositing a first layer of additional material during the cure process with the dichlorosilane gas so that the additional material is present at a conclusion of the cure process, and (b) depositing a second layer of additional material after the cure process with a silicon tetrachloride gas, and
• wherein the first layer of additional material and the second layer of additional material are each formed before utilizing the patterned photoresist as an etch mask and transferring the pattern, the first layer of additional material has a different thickness than the second layer of additional material, and the first layer of additional material and the second layer of additional material are formed of silicon containing materials which are different from each other.