Method of making microelectronic contact structures

A method of forming microelectronic spring contact elements on a sacrificial substrate, comprising:

• providing a blanket layer of silicon nitride on a surface of the sacrificial substrate;
• creating a plurality of openings through the silicon nitride layer, thereby exposing the surface of the sacrificial substrate;
• etching the sacrificial substrate within the openings to form a corresponding plurality of first trenches, each extending to a first depth below the surface of the sacrificial substrate;
• masking a portion of the first trenches;
• etching the sacrificial substrate within an unmasked portion of the first trenches to form a corresponding plurality of second trenches each at a second depth that is different than the first depth;
• depositing metallic material into the first and second trenches, the metallic material deposited into each of the first trenches and corresponding second trenches serving as one of a plurality of resulting microelectronic spring contact elements.

A method of making a plurality of microelectronic spring contact elements that are supported in a predefined spatial relationship with respect to one another, the method comprising the steps of:

• forming a first trench at a first depth below a surface of a sacrificial substrate;
• forming a second trench at a second depth, which is different than the first depth, below the surface of the sacrificial substrate;
• depositing at least one layer of metallic material into the first and second trenches and portions of the surface of the sacrificial substrate between the first and second trenches;
• masking a portion of the metallic material;
• and
• etching the metallic material within an unmasked portion of the metallic material to form the plurality of microelectronic spring contact elements.