Semiconductor Structure and Method of Forming the Same

A method comprising:

• forming a metal region over an adhesion layer, wherein the adhesion layer comprises a first portion overlapped by the metal region, and a second portion extending beyond an edge of the metal region;
• etching the adhesion layer, wherein the second portion of the adhesion layer is removed by the etching, and wherein a remaining part of the first portion of the adhesion layer remains after the etching;
• and
• after the adhesion layer is etched, re-etching the metal region.

A method comprising:

• forming a conductive feature comprising:
• an adhesion layer formed of a first conductive material;
• and
• a metal region over the adhesion layer, wherein the metal region is formed of a second conductive material different from the first conductive material;
• performing a first etching process to etch the adhesion layer;
• and
• after the first etching process, performing a second etching process to etch the metal region.