Patent ID: 8441091

Claim:
A photodiode assembly comprising: a semiconductor substrate; a photodiode cell in the substrate, the photodiode cell including a first volume of the substrate that is doped with a first type of dopant; a ground diffusion region in the substrate, the ground diffusion region including a second volume of the substrate that is doped with a second type of dopant having an opposite charge relative to the first type of dopant; and a guard band in the substrate and at least partially extending around an outer periphery of the photodiode cell, the guard band including a third volume of the substrate that is doped with the first type of dopant, at least one of the ground diffusion region or the guard band conductively coupled with a ground reference to conduct one or more of electrons or holes that drift from the photodiode cell through the substrate, wherein the guard band is disposed closer to the photodiode cell than the ground diffusion region, and wherein the commonly doped volume of the guard band is separated from the photodiode cell by a separation portion of the substrate that continuously extends from the photodiode cell to the guard band and that is not doped with the second type of dopant.