This photodiode array is equipped with a plurality of photodiodes formed on a semiconductor substrate. Each of the photodiodes has: a first semiconductor region of a first conductive type provided on the semiconductor substrate a second semiconductor region of a second conductive type constituting the first semiconductor region and a photodetection region, and provided on one surface of the semiconductor substrate in relation to the first semiconductor region so as to surround a prescribed region and a through electrode electrically connected to the second semiconductor region, and positioned inside a through-hole for passing between the one surface and the other surface of the semiconductor substrate so as to pass through the first semiconductor region and the prescribed region. Furthermore, the through electrode includes a section which widens from the one surface toward the other surface.本發明之光二極體陣列包括形成於半導體基板之複數個光二極體。光二極體之各者具有：第1導電型之第1半導體區域，其設置於半導體基板；第2導電型之第2半導體區域，其以包圍特定區域之方式，相對於第1半導體區域而設置於半導體基板之一面側，且與第1半導體區域一同構成光檢測區域；及貫通電極，其設置於以通過第1半導體區域及特定區域之方式貫通一面與半導體基板之另一面之間之貫通孔內，且與第2半導體區域電性連接。貫通孔包含自一面向另一面擴大之部分。
