Patent ID: 7205624

Claim:
An optical detector comprising: a substrate; an island of detector material formed on and occupying only a portion of a surface of the substrate, said island having a horizontally oriented top end, a vertically oriented first sidewall, and vertically oriented second sidewall that is opposite said first sidewall, said island having a first doped region extending into the island through first sidewall and forming a first conductive region that extends down into the island of detector material, said island also having a second doped region extending into the island through the second sidewall and forming a second conductive region that extends down into island of the detector material, the first and second conductive regions each having a top end that is part of the top end of the island and together in combination with the intervening detector material defining a horizontally-oriented device structure on the substrate; an isolation material formed on the surface of the substrate and covering the doped regions of the first and second sidewalls of the island at least up to the top of the island; a first electrical connection to the top end of the first conductive region; and a second electrical connection to the top end of the second conductive region.