Fast timing with induced current detectors

Vertically integrated (3D) combinations of sensors and electronics provide the ability to fabricate small, fine pitch pixels with very small total capacitance monolithically integrated with complex circuitry. The small capacitance, enabled by the fine pixel pitch and low interconnect capacitance available in 3D hybrid bonding, provides excellent signal/noise with moderate power. This combination enables fabrication of integrated sensors and electronics with both excellent position and time resolution. We describe the capabilities of such a system and the limitations imposed by geometry and power. We describe how a similar geometry can be used to provide very fast timing of x-ray arrival in a thick sensor by utilizing the transient induced current in a field of pixels.