Radiation detector having a bandgap engineered absorber

A method for sensing radiation, comprising:

• receiving radiation by a first radiation absorption layer;
• in response to receiving the radiation by the first radiation absorption layer, generating carriers;
• creating an electric field gradient in a second radiation absorption layer in response to a bias voltage being applied to the second radiation absorption layer;
• drifting the carriers through the second radiation absorption layer in response to the electric field gradient;
• and
• outputting a signal representative of the generated and drifted carriers for measuring the sensed radiation.

A method of manufacturing a photodiode, comprising:

• providing a substrate;
• depositing a first passivation layer on the substrate;
• depositing a bandgap engineered absorber onto the passivation layer;
• depositing a second passivation layer onto the bandgap engineered absorber;
• bonding the second passivation layer onto a readout integrated circuit layer, the readout integrated circuit including a conductor;
• removing the substrate from the first passivation layer, thereby exposing the first passivation layer;
• forming a via through the absorber and passivation layers to form p/n-junctions on both sides of the via;
• and
• connecting the n-side of the p/n-junctions of the via to the conductor of the readout input circuit through a metal layer of the via.