Visible ray sensor and light sensor including the same
View Patent ↗The present invention relates to a visible ray sensor and a light sensor capable of improving photosensitivity by preventing photodegradation. The visible ray sensor may include: a substrate, a light blocking member formed on the substrate, and a visible ray sensing thin film transistor formed on the light blocking member. The light blocking member may be made of a transparent electrode, a band pass filter, or an opaque metal.
1. A visible ray sensor, comprising:
a substrate;
a light blocking member disposed on the substrate; and
a visible ray sensing thin film transistor disposed on the light blocking member and comprising a first gate insulating layer and a first gate electrode,
wherein the first gate insulating layer is disposed on the light blocking member, which is under the first gate insulating layer, and comprises a first contact hole that exposes the light blocking member,
wherein the first gate insulation layer is electrically connected to a bottom surface of a first semiconductor layer of the thin film transistor,
wherein source and drain electrodes are electrically connected to a portion of the top surface of the semiconductor layer, respectively,
wherein the first gate electrode is electrically connected to a top surface of a second gate insulation layer at least at the central portion of the first semiconductor layer between the source and drain electrodes,
wherein a portion of a bottom surface of the second gate insulation layer is electrically connected to a central portion of the top surface of the first semiconductor layer between the source and drain electrodes, and the second gate insulation layer comprises a second contact hole aligned to the first contact hole such that the light blocking member is exposed, and
wherein the first gate electrode is disposed on the first gate insulating layer and directly connected to the light blocking member through the first and second contact holes.
2. The visible ray sensor of claim 1 , wherein
the light blocking member comprises a transparent electrode.
3. The visible ray sensor of claim 1 , wherein
the transparent electrode comprises polycrystalline indium tin oxide or polycrystalline indium zinc oxide.
4. The visible ray sensor of claim 1 , wherein
the light blocking member comprises a plurality of openings.
5. The visible ray sensor of claim 4 , wherein
the light blocking member comprises a band pass filter.
6. The visible ray sensor of claim 5 , wherein
the band pass filter is configured to block visible rays.
7. The visible ray sensor of claim 6 , wherein
the light blocking member comprises a material comprising amorphous germanium or a compound of amorphous germanium.
8. The visible ray sensor of claim 4 , wherein
the light blocking member comprises an opaque metal.