Solid-state image pickup device and electronic apparatus having a wall between the first pixel and the second pixel

An electronic apparatus, comprising:

• a lens;
• a digital signal processing circuitry;
• and
• a light detecting device, comprising:
• a first photoelectric conversion region disposed in a substrate wherein the substrate comprises a first surface and a second surface opposite the first surface, the first surface being a light incident surface of the substrate;
• a second photoelectric conversion region disposed in the substrate and adjacent to the first photoelectric conversion region;
• a first on-chip lens disposed above the first surface of the substrate, the first on-chip lens corresponding to the first photoelectric conversion region;
• and
• a second on-chip lens disposed above the first surface of the substrate and disposed adjacent to the first on-chip lens, the second on-chip lens corresponding to the second photoelectric conversion region,
• wherein the first photoelectric conversion region and the first on-chip lens are a part of a first pixel and the second photoelectric conversion region and the second on-chip lens are a part of a second pixel,
• the light detection device further comprising:
• a first wall disposed between the first pixel and the second pixel, wherein a part of the first wall is disposed at the first surface of the substrate;
• a second wall disposed between the first pixel and the second pixel, wherein a part of the second wall is disposed at the second surface of the substrate;
• and
• a first semiconductor region disposed in the substrate, wherein, in a cross-sectional view, the first semiconductor region is disposed between a first portion of the second wall and a second portion of the second wall.