Solid-state image pickup device, image pickup system including the same, and method for manufacturing the same

摘要

A solid-state image pickup device including a photoelectric conversion element, a floating diffusion, and an element isolation region that are disposed above a first semiconductor region has a second semiconductor region of a first conductivity type disposed on the first semiconductor region. An interface between the first semiconductor region and a portion of the second semiconductor region corresponding to the photoelectric conversion element is located at a first depth, whereas the interface between the first semiconductor region and a portion of the second semiconductor region disposed under the element isolation region and the floating diffusion is located at a second depth smaller than the first depth.

主权项

1. A solid-state image pickup device comprising:
a semiconductor substrate including a first photoelectric conversion element, a first floating diffusion, a first transfer gate disposed between the first photoelectric conversion element and the first floating diffusion, a second photoelectric conversion element, a second floating diffusion, and a second transfer gate disposed between the second photoelectric conversion element and the second floating diffusion; a first color filter, disposed above the first photoelectric conversion element, configured to transmit light of a first wavelength; and a second color filter, disposed above the second photoelectric conversion element, configured to transmit light of a second wavelength being longer than the first wavelength, wherein the first photoelectric conversion element includes a first semiconductor region of a first conductivity type, a second semiconductor region of a second conductivity type configured to store charge, a third semiconductor region having an impurity concentration lower than the second semiconductor region of the second conductivity type and a fourth semiconductor region of the first conductivity type, the first semiconductor region, the second semiconductor region, the third semiconductor region and the fourth semiconductor region being arranged in this order in a depth direction of the semiconductor substrate from a light receiving surface of the first photoelectric conversion element, wherein the second photoelectric conversion element includes a fifth semiconductor region of a first conductivity type, a sixth semiconductor region of a second conductivity type configured to store charge, a seventh semiconductor region having an impurity concentration lower than the sixth semiconductor region of the second conductivity type and a eighth semiconductor region of the first conductivity type, the fifth semiconductor region, the sixth semiconductor region, the seventh semiconductor region and the eighth semiconductor region being arranged in this order in a depth direction of the semiconductor substrate from a light receiving surface of the second photoelectric conversion element, and wherein an interface between the third semiconductor region and the fourth semiconductor region is located at a depth shallower than a depth at which an interface between the seventh semiconductor region and the eighth semiconductor region is situated.