Metal resistors having nitridized dielectric surface layers and nitridized metal surface layers

A method of forming a semiconductor structure, said method comprising:

• providing a dielectric-containing substrate comprising at least an interconnect dielectric material layer containing a first nitridized dielectric surface layer having a first nitrogen content, and a second nitridized dielectric surface layer having a second nitrogen content that differs from the first nitrogen content;
• forming a metal layer on said first nitridized dielectric surface layer and on said second nitridized dielectric surface layer;
• patterning a first portion of said metal layer and said first nitridized dielectric surface layer to provide a first resistor stack of, from bottom to top, a remaining portion of said first nitridized dielectric surface layer and a first remaining portion of said metal layer, and a second portion of said metal layer and said second nitridized dielectric surface layer to provide a second resistor stack of, from bottom to top, a remaining portion of said second nitridized dielectric surface layer and a second remaining portion of said metal layer;
• performing a nitridation process to provide a first nitridized metal surface layer having a first nitrogen content within said first remaining portion of said metal layer, wherein said remaining portion of said first nitridized dielectric surface layer, said first remaining portion of said metal layer and said first nitridized metal surface layer provide a first metal resistor structure;
• and
• performing another nitridation process to provide a second nitridized metal surface layer having a second nitrogen content that differs from said the first nitrogen content of said first nitridized metal surface layer and within said second remaining portion of said metal layer, wherein said remaining portion of said second nitridized dielectric surface layer, said second remaining portion of said metal layer and said second nitridized metal surface layer provide a second metal resistor structure.