Rear-illuminated-type photodiode array

A rear-illuminated-type photodiode array comprising:

• (a) a first-electroconductive-type semiconductor substrate;
• (b) a first-electroconductive-type electrode that:
• (b1) is at a rear side of the semiconductor substrate;
• and
• (b2) has a plurality of openings arranged one- or two-dimensionally;
• (c) an antireflective coating at each of the openings of the first-electroconductive-type electrode;
• (d) a first-electroconductive-type absorption layer that:
• (d1) is at a front-face side of the semiconductor substrate;
• and
• (d2) has an absorption edge wavelength of λgr;
• (e) a leakage-lightwave-absorbing layer that:
• (e1) is over the entire absorption layer;
• and
• (e2) has an absorption edge wavelength, λga, longer than the absorption edge wavelength, λgr, of the absorption layer (λga>λgr);
• (f) a plurality of lightwave receiving parts comprising:
• (f1) a plurality of second-electroconductive-type regions that:
• (f11) penetrate through the leakage-lightwave-absorbing layer from the top surface and extend partially into the absorption layer;
• and
• (f12) are arranged one- or two-dimensionally at positions at the top surface so as to be substantially aligned with and opposite positions of the antireflective coatings;
• and
• (g) a second-electroconductive-type electrode provided on the top surface of each of the second-electroconductive-type regions,
• the array further comprising a window layer that is disposed between the absorption layer and the leakage-lightwave-absorbing layer, the window layer having an absorption edge wavelength, λgw, shorter than the absorption edge wavelength, λgr, of the absorption layer (λgw<λgr), and the second-electroconductive-type regions penetrating through the window layer.