Abstract: A semiconductor imaging device, for use, for example, in medical diagnosis and non-destructive testing, includes a radiation detector semiconductor substrate and a readout substrate connected to the detector by means of low temperature solder bumps A low temperature solder is preferably a lead-tin based solder having a melting point below that of eutectic lead-tin solder. Preferred embodiments of such low temperature solder include bismuth based alloys such as, for example, the eutectic (52 wt-%Bi, 32 wt-%Pb, 16 wt-%Sn) alloy which has a melting point under 100.degree. C.

Abstract: A semiconductor high-energy radiation imaging device having an array of pixel cells includes a semiconductor detector substrate and a semiconductor readout substrate. The semiconductor detector substrate includes an array of pixel detector cells, each of which directly generates charge in response to incident high-energy radiation. The semiconductor readout substrate includes an array of individually addressable pixel circuits, each of which is connected to a corresponding pixel detector cell to form a pixel cell. Each pixel circuit includes charge accumulation circuitry for accumulating charge directly resulting from high-energy radiation incident on a corresponding pixel detector cell, readout circuitry for reading the accumulated charge, and reset circuitry for resetting the charge accumulation circuitry. The charge accumulation circuitry has a charge storage capacity sufficient to store at least 1.