US 12,142,701 B2
Light receiving device
Takatomo Isomura, Tochigi (JP); and Etsuji Omura, Tochigi (JP)
Assigned to Dexerials Corporation, Tochigi (JP)
Filed by Dexerials Corporation, Tochigi (JP)
Filed on Nov. 22, 2023, as Appl. No. 18/518,407.
Application 18/518,407 is a continuation of application No. PCT/JP2022/048201, filed on Dec. 27, 2022.
Prior Publication US 2024/0213383 A1, Jun. 27, 2024
Int. Cl. H01L 31/0232 (2014.01); H01L 31/028 (2006.01); H01L 31/0304 (2006.01); H01L 31/0328 (2006.01)
CPC H01L 31/02327 (2013.01) [H01L 31/028 (2013.01); H01L 31/0304 (2013.01); H01L 31/0328 (2013.01)] 4 Claims
OG exemplary drawing
 
1. A light receiving device having a semiconductor light receiving element in which a photodiode is formed on a main surface side of a first semiconductor substrate, and a concave mirror that reflects incident light toward the semiconductor light receiving element; wherein
the concave mirror is provided with a flat first surface of a second semiconductor substrate that is transparent to incident light, a convex surface formed on a second surface opposite to the first surface in a convex shape toward a side opposite to the first surface, and a reflective film formed on the convex surface, and the incident light incident from the first surface is reflected by the reflective film and focused at a condensing position near the first surface,
the semiconductor light receiving element is fixed to the first surface of the second semiconductor substrate so as to overlap the light condensing position,
wherein a back surface facing the main surface of the first semiconductor substrate is fixed to the first surface of the second semiconductor substrate with an adhesive resin that is transparent to incident light and a thickness of the adhesive resin is adjusted to suppress reflection of light reflected by the concave mirror when the light enters the first semiconductor substrate from the second semiconductor substrate by utilizing light interference.