Photo cell devices for phase-sensitive detection of light signals

摘要

Embodiments relate to photo cell devices. In one embodiment, a trench-based photo cells provides very fast capture of photo-generated charge carriers, particularly when compared with conventional approaches, as the trenches of the photo cells create depleted regions deep within the bulk of the substrate that avoid the time-consuming diffusion of carriers.

主权项

1. A photo cell comprising:
a substrate; and at least two vertical trenches formed in the substrate and laterally spaced apart from one another such that a doping type of a bulk of the substrate around and between the at least two vertical trenches is the same, wherein when the photo cell operates in a depletion mode a space charge region extends laterally in the substrate with a first trench of the at least two vertical trenches disposed in the space charge region and a second trench of the at least two vertical trenches disposed in a neutral region of the substrate, wherein a depth of the at least two trenches is related to a wavelength of a signal source.