Solid-state image sensing device with detecting units having a microlens
A solid-state image sensing device has a plurality of detection units periodically arranged as a two-dimensional array on a substrate. Each of the detection units includes a visible light detector and an infrared light detector arranged on the same optical axis in a vertical direction so that the visible light detector and the infrared light detector overlap with each other. Each of the detection units also includes a signal readout circuit provided in the substrate so as to output signals of the visible light detector and the infrared light detector as time-series signals.
1. A solid-state image sensing device comprising:
a substrate;
a plurality of detection units periodically arranged as a two-dimensional array for the substrate, each of the detection units including a visible light detector and an infrared light detector arranged on the same optical axis in a vertical direction so that the visible light detector and the infrared light detector overlap with each other; and
a signal readout circuit provided in the substrate so as to output signals of the visible light detector and the infrared light detector as time-series signals,
wherein each of the detection units further includes a microlens provided between the visible light detector and the infrared light detector.
2. The solid-state image sensing device as recited in claim 1 , wherein the microlens is covered with a microlens protective film.
3. The solid-state image sensing device as recited in claim 1 , wherein the microlens is made of polyimide.
4. The solid-state image sensing device as recited in claim 1 , wherein the infrared light detector includes:
support legs, and
a diaphragm lifted up from the substrate and held in midair by the support legs, the diaphragm being isolated thermally from the substrate.
5. The solid-state image sensing device as recited in claim 4 , wherein the diaphragm includes a bolometer film for detecting a temperature change, and
each of the detection units is configured to detect infrared light by a resistance change of the bolometer film that is caused by heat resulting from an incident infrared ray absorbed into the diaphragm.
6. The solid-state image sensing device as recited in claim 4 , wherein each of the visible light detectors includes a visible light detection layer provided in the substrate, and
each of the detection units is configured so that an incident visible ray is transmitted through the diaphragm, condensed by the microlens, and directed to the visible light detection layer.
7. The solid-state image sensing device as recited in claim 4 , wherein the microlens is provided within a cavity formed below the diaphragm and is positioned right above the visible light detection layer.