Solid-state imaging device

摘要

In a solid-state imaging device, N regions serving as photoelectric conversion diodes are formed on outer peripheries of P regions in upper portions of island-shaped semiconductors formed on a substrate, and P+ regions connected to a pixel selection line conductive layer are formed on top layer portions of upper ends of the island-shaped semiconductors so as to adjoin the N regions and the P regions. In the P+ regions, a first P+ region has a thickness less than a second P+ region, and the second P+ region has a thickness less than a third P+ region.

主权项

1. A solid-state imaging device including a plurality of pixels which are formed of island-shaped semiconductors, the plurality of pixels being two-dimensionally arranged in a pixel region, comprising:
first semiconductor regions formed on a substrate; base semiconductor regions formed on the first semiconductor regions, the base semiconductor regions forming the island-shaped semiconductors; second semiconductor regions formed on outer peripheries of the base semiconductor regions which are spaced away from the first semiconductor regions, the second semiconductor regions forming diodes together with the base semiconductor regions; and third semiconductor regions formed above the second semiconductor regions so as to adjoin the base semiconductor regions, the third semiconductor regions having a conductivity type opposite to a conductivity type of the second semiconductor regions, wherein the third semiconductor region includes a sufficient quantity of acceptor or donor impurities that signal charges generated by absorption of incident light incident on top surfaces of upper ends of the island-shaped semiconductors in the third semiconductor regions are recombined and disappear in the third semiconductor regions, the island-shaped semiconductors are formed to include the third semiconductor regions having at least two different thicknesses, in the island-shaped semiconductors, a color filter of a primary color or a complementary color is formed over the third semiconductor region of a first island-shaped semiconductor including the third semiconductor region having the smallest thickness or a second island-shaped semiconductor including the third semiconductor region having the second smallest thickness, and light transmitted through the color filter includes a light wavelength component which undergoes light absorption and accumulation of signal charges in the diode region in the first island-shaped semiconductor or second island-shaped semiconductor located below the color filter, and the solid-state imaging device performs an imaging operation which includes a photoelectric conversion operation for absorbing light incident on the top surfaces of the upper ends of the island-shaped semiconductors, in diode regions formed by the second semiconductor regions and the base semiconductor regions, and generating signal charges, a signal charge accumulating operation for accumulating the generated signal charges in the diode regions, an accumulated signal charge quantity read operation for sensing the quantity of signal charges accumulated in the diode regions by detecting a source-drain current flowing through junction field-effect transistors, the junction field-effect transistors having sources or drains which are defined by the first semiconductor regions or the third semiconductor regions, gates which are defined by the second semiconductor regions, and channels which are defined by the base semiconductor regions surrounded by the second semiconductor regions, and a signal charge discharging operation for discharging the signal charges accumulated in the diode regions to the first semiconductor regions.