Band-pass filter for stacked sensor

A stacked image sensor device, comprising:

• a first image sensor element disposed within a first substrate and configured to generate electrical signals from electromagnetic radiation within a first range of wavelengths, wherein the first substrate has a first surface configured to receive incident radiation and a second surface opposing the first surface;
• a second image sensor element disposed within a second substrate and configured to generate electrical signals from electromagnetic radiation within a second range of wavelengths that is different than the first range of wavelengths;
• and
• a first band-pass filter arranged between the second surface of the first substrate and the second substrate and comprising alternating layers of a first material having a first refractive index and a second material having a second refractive index that is different than the first refractive index, wherein the first band-pass filter is configured to pass electromagnetic radiation within the second range of wavelengths and to reflect electromagnetic radiation within the first range of wavelengths;
• a first dielectric structure arranged along the second surface of the first substrate and comprising a first plurality of stacked inter-level dielectric (ILD) layers surrounding a first plurality of conductive interconnect layers;
• a second dielectric structure arranged along a surface of the second substrate and comprising a second plurality of stacked ILD layers surrounding a second plurality of conductive interconnect layers;
• and
• a through-substrate-via (TSV) extending through the second substrate and electrically coupling the first plurality of conductive interconnect layers to the second plurality of conductive interconnect layers, wherein the TSV extends through the first band-pass filter.

A three-dimensional integrated chip, comprising:

• a first integrated chip (IC) die having a first image sensor element configured to generate electrical signals from electromagnetic radiation within a first range of wavelengths;
• a second IC die having a second image sensor element configured to generate electrical signals from electromagnetic radiation within a second range of wavelengths that is different than the first range of wavelengths;
• and
• a first band-pass filter arranged between the first IC die and the second IC die and configured to reflect electromagnetic radiation that is within the first range of wavelengths, wherein the first band-pass filter comprises:
• a first layer of silicon;
• a first layer of silicon dioxide;
• and
• a second layer of silicon, wherein the first layer of silicon dioxide continuously extends from a first surface contacting the first layer of silicon to a second surface contacting the second layer of silicon.