Photo-detecting apparatus
Methods, devices, apparatus, and systems for photo-detecting are provided. In one aspect, a photo-detecting apparatus includes: a pixel having an absorption region configured to receive an optical signal and to generate photo-carriers in response to the optical signal, a substrate supporting the absorption region, and at least one additional region formed in the substrate. The absorption region includes a first material, the substrate includes a second material different from the first material. The at least one additional region includes a third material different from the second material. A total area of the absorption region and the at least one additional region is at least 20% of an area of the pixel.
1 . A photo-detecting apparatus, comprising:
a pixel comprising an absorption region configured to receive an optical signal and to generate photo-carriers in response to the optical signal, wherein the absorption region includes a first material, wherein the first material comprises germanium;
a substrate supporting the absorption region, wherein the substrate includes a second material different from the first material, wherein the second material comprises silicon;
a light shield comprising an optical window; and
one or more density compensation structures comprising a third material and arranged to provide a predetermined density distribution of the first material and the third material, wherein the third material comprises germanium,
wherein the optical window is arranged over the absorption region such that the absorption region receives the optical signal through the optical window,
wherein the light shield is arranged over the one or more density compensation structures to block light from entering the one or more density compensation structures, and
wherein a total area of the absorption region and the one or more density compensation structures is at least 20% of an area of the pixel.
2 . The photo-detecting apparatus of claim 1 , further comprising an isolation region formed in the substrate.
3 . The photo-detecting apparatus of claim 2 , wherein the isolation region surrounds the absorption region, and the isolation region is between the absorption region and the one or more density compensation structures.
4 . The photo-detecting apparatus of claim 2 , wherein the isolation region surrounds the absorption region and the one or more density compensation structures.
5 . The photo-detecting apparatus of claim 1 , wherein the third material comprises a metal or an insulating material.
6 . The photo-detecting apparatus of claim 1 , wherein the one or more density compensation structures comprise multiple additional regions arranged around the absorption region.
7 . The photo-detecting apparatus of claim 1 , wherein the absorption region is doped with a first dopant having a first conductivity type, and the one or more density compensation structures are doped with a second dopant having the first conductivity type.
8 . The photo-detecting apparatus of claim 1 , further comprising a blocking layer surrounding the one or more density compensation structures.
9 . The photo-detecting apparatus of claim 1 , further comprising an isolation structure arranged to lower or prevent signal cross-talk between adjacent pixels, the isolation structure comprising an oxide material, a nitride material, or a silicon material.
10 . A photo-detecting apparatus, comprising:
two adjacent pixels each comprising an absorption region configured to receive an optical signal and to generate photo-carriers in response to the optical signal, wherein the absorption region includes a first material, wherein the first material comprises germanium;
a substrate supporting the two adjacent pixels, wherein the substrate includes a second material different from the first material, wherein the second material comprises silicon;
a light shield comprising two optical windows;
one or more density compensation structures comprising a third material and arranged to provide a predetermined density distribution of the first material and the third material, wherein the third material comprises germanium; and
two isolation regions each surrounding a respective absorption region of the absorption regions of the two adjacent pixels,
wherein each of the two optical windows is arranged over a respective absorption region of the two adjacent pixels such that the respective absorption region receives the optical signal through the optical window, and wherein the light shield is arranged over the one or more density compensation structures to block light from entering the one or more density compensation structures.
11 . The photo-detecting apparatus of claim 10 , wherein, for each of the two adjacent pixels, a total area of the absorption region and the one or more density compensation structures is at least 20% of an area of the pixel.
12 . The photo-detecting apparatus of claim 10 , wherein the third material comprises a metal or an insulating material.
13 . The photo-detecting apparatus of claim 10 , wherein one of the two isolation regions surrounds the one or more density compensation structures and the respective absorption region.
14 . The photo-detecting apparatus of claim 10 , wherein the absorption region is doped with a first dopant having a first conductivity type, and the one or more density compensation structures are doped with a second dopant having the first conductivity type.
15 . The photo-detecting apparatus of claim 10 , further comprising an isolation structure arranged to lower or prevent signal cross-talk between adjacent pixels, the isolation structure comprising an oxide material, a nitride material, or a silicon material.
16 . A system, comprising:
a transmitter;
a receiver;
a signal processor in electrical communication with the receiver; and
a controller in electrical communication with the signal processor and the transmitter;
wherein the receiver includes one or more photo-detecting apparatus, each of the one or more photo-detecting apparatus comprising:
a pixel comprising an absorption region configured to receive an optical signal and to generate photo-carriers in response to the optical signal, wherein the absorption region includes a first material, wherein the first material comprises germanium;
a substrate supporting the absorption region, wherein the substrate includes a second material different from the first material, wherein the second material comprises silicon;
a light shield comprising an optical window; and
one or more density compensation structures comprising a third material and arranged to provide a predetermined density distribution of the first material and the third material, wherein the third material comprises germanium,
wherein the optical window is arranged over the absorption region such that the absorption region receives the optical signal through the optical window,
wherein the light shield is arranged over the one or more density compensation structures to block light from entering the one or more density compensation structures, and
wherein a total area of the absorption region and the one or more density compensation structures is at least 20% of an area of the pixel.
17 . The system of claim 16 , wherein one of the one or more photo-detecting apparatus further comprises an isolation region formed in the substrate,
wherein the isolation region surrounds the absorption region, and the isolation region is between the absorption region and the one or more density compensation structures.
18 . The imaging system of claim 16 , wherein one of the one or more photo-detecting apparatus further comprises an isolation region formed in the substrate,
wherein the isolation region surrounds the absorption region and the one or more density compensation structures.
19 . The system of claim 16 , wherein the absorption region is doped with a first dopant having a first conductivity type, and the one or more density compensation structures are doped with a second dopant having the first conductivity type.
20 . The system of claim 16 , further comprising an isolation structure arranged to lower or prevent signal cross-talk between adjacent pixels, the isolation structure comprising an oxide material, a nitride material, or a silicon material.