SEMICONDUCTOR PHOTODIODE
A semiconductor photodiode. The semiconductor photodiode including: an input waveguide, arranged to receive an optical signal at a first port and provide the optical signal from the second port; a photodiode waveguide, arranged to receive the optical signal from the second port of the input waveguide, and at least partially convert the optical signal into an electrical signal; and an electro-static defence component, located adjacent to the photodiode waveguide. The electro-static defence component and the photodiode waveguide are electrically connected in parallel.
1 . A semiconductor photodiode, the semiconductor photodiode including:
an input waveguide, arranged to receive an optical signal at a first port and provide the optical signal from a second port;
a photodiode waveguide, arranged to receive the optical signal from the second port of the input waveguide, and at least partially convert the optical signal into an electrical signal; and
an electro-static defence component, located adjacent to the photodiode waveguide;
wherein the electro-static defence component and the photodiode waveguide are electrically connected in parallel.
2 . The semiconductor photodiode of claim 1 , wherein the photodiode waveguide and the electro-static defence component are electrically connected via a pair of electrodes, each electrode having a wider cross-section in a region adjacent to the electro-static defence component than a region adjacent to the photodiode waveguide.
3 . The semiconductor photodiode of claim 1 , wherein the photodiode waveguide and the electro-static defence component are electrically connected via a pair of doped regions of semiconductor, each doped region of semiconductor having a wider cross-section in a portion adjacent to the electro-static defence component than a portion adjacent to the photodiode waveguide.
4 . The semiconductor photodiode of claim 1 , wherein the photodiode waveguide includes first and second doped regions extending from a slab adjacent to the photodiode waveguide along respective sidewalls of the photodiode waveguide.
5 . The semiconductor photodiode of claim 4 , wherein:
the first and second doped regions of the photodiode waveguide each contain a first and second sub-region, the first sub-region of each doped region containing a higher concentration of dopants than the second sub-region of each doped region, and
wherein the first sub-regions of the first and second doped regions of the photodiode waveguide extend only along the slab adjacent to the photodiode waveguide.
6 . The semiconductor photodiode of claim 5 , wherein the electro-static defence component includes first and second doped regions extending from the slab adjacent to the photodiode waveguide up respective sidewalls of a waveguide within the electro-static defence component, which is coupled to the photodiode waveguide.
7 . The semiconductor photodiode of claim 6 , wherein:
the first and second doped regions of the electro-static defence component each contain a first and second sub-region, the first sub-region of each doped region containing a higher concentration of dopants than the second sub-region of each doped region, and
wherein the first and second sub-regions of the first and second doped regions of the electro-static defence component extend along a slab and also up respective sidewalls of the waveguide within the electro-static defence component.
8 . The semiconductor photodiode of claim 1 , wherein
the photodiode waveguide and the electro-static defence component each contain a P-I-N junction, and
wherein a width of the intrinsic region of the P-I-N junction within the electro-static defence component is smaller than a corresponding width of the intrinsic region of the P-I-N junction within the photodiode waveguide.
9 . The semiconductor photodiode of claim 1 , wherein the electro-static defence component is wider than the photodiode waveguide.
10 . The semiconductor photodiode of claim 9 , wherein the photodiode waveguide includes a tapered region, which tapers from a width of the photodiode waveguide to the width of the electro-static defence component.
11 . The semiconductor photodiode of claim 10 , wherein the electro-static defence component and the photodiode waveguide each comprise a doped region, and
wherein the doped region of the electro-static defence component is further from a substrate of the semiconductor photodiode than the doped region of the photodiode waveguide.
12 . The semiconductor photodiode of claim 1 , wherein the semiconductor photodiode further comprises a substrate, a device layer, and an insulator layer located between the substrate and the device layer, and wherein the photodiode waveguide and the electro-static defence component are each located on a same opposing side of the device layer to the insulator layer.
13 . The semiconductor photodiode of claim 1 , wherein the semiconductor photodiode further comprises a substrate, a device layer, and a semiconductor seed layer located between the substrate and the device layer, and wherein the photodiode waveguide and the electro-static defence component are each located on a same opposing side of the device layer to the semiconductor seed layer.
14 . The semiconductor photodiode of claim 13 , wherein the semiconductor seed layer is an epitaxial crystalline layer.
15 . The semiconductor photodiode of claim 13 , further comprising an insulator layer located on one or more lateral sides of the semiconductor seed layer.