Carbon nanotube spring contact structures with mechanical and electrical components

A probe card assembly comprising:

• an electrical interface to a tester;
• a plurality of probes disposed to contact electronic devices to be tested;
• and
• electrical connections between the interface and the probes,
• wherein each of the probes comprises a spring contact structure comprising:
• a structural component comprising a group of carbon nanotubes, the structural component being a resilient spring structure and having first mechanical characteristics and first electrical characteristics;
• and
• a conduction component having second electrical characteristics that are different than the first electrical characteristics of the structural component, the conduction component further having second mechanical characteristics that are different than the first mechanical characteristics of the structural component,
• wherein:
• the structural component and the conduction component are distinct structures,
• the structural component provides a dominant mechanical characteristic of the composite spring contact structure, and
• the conduction component provides a dominant electrical characteristic from one end of the composite spring contact structure to an opposite end of the composite spring contact structure.