Probe head structure

A probe head structure, comprising:

• a substrate having a top surface and a bottom surface;
• a probe pillar passing through the substrate, wherein the probe pillar has a protruding portion protruding from the bottom surface, and the probe pillar comprises a conductive pillar and a seed layer between the conductive pillar and the substrate and surrounding the conductive pillar;
• a redistribution structure over the top surface of the substrate and the probe pillar, wherein a first sidewall of the redistribution structure is substantially level with a second sidewall of the substrate, and the redistribution structure is spaced apart from the conductive pillar by the seed laver;
• a wiring substrate over the redistribution structure;
• and
• a conductive bump connected between the wiring substrate and the redistribution structure.

A probe head structure, comprising:

• a substrate having a top surface and a bottom surface;
• a probe pillar passing through the substrate, wherein the probe pillar has a protruding portion protruding from the bottom surface;
• a conductive layer covering the protruding portion and in contact with the protruding portion and the substrate;
• and
• a redistribution structure over the top surface of the substrate and the probe pillar, wherein a first sidewall of the redistribution structure is substantially level with a second sidewall of the substrate, the redistribution structure has a dielectric structure and a wiring layer embedded in the dielectric structure, the wiring layer is electrically connected to the probe pillar, and the probe pillar is physically spaced apart from the wiring layer by a portion of the dielectric structure.