Semiconductor photonic devices with enhanced responsivity and reduced stray light

Abstract

In accordance with the invention, a photonic device comprises a semiconductor substrate including at least one circuit component comprising a metal silicide layer and an overlying layer including at least one photoresponsive component. The metal silicide layer is disposed between the circuit component and the photoresponsive component to prevent entry into the circuit component of light that penetrates the photoresponsive component. The silicide layer advantageously reflects the light back into the photoresponsive element. In addition, the overlying layer can include one or more reflective layers to reduce entry of oblique light into the photoresponsive component. In an advantageous embodiment, the substrate comprises single-crystal silicon including one or more insulated gate field effect transistors (IGFETs), and/or capacitors, and the photoresponsive element comprises germanium and/or germanium alloy epitaxially grown from seeds on the silicon. The metal silicide layer can comprise the gate of the IGFET and/or an electrode of the capacitor.

1 .- 27 . (canceled) 
   
   
       28 . A device comprising:
 a photoresponsive component integrated with a substrate; and   a layer configured to preclude substantially all light passing through the photoresponsive component from reaching the substrate.   
   
   
       29 . The device of  claim 28 , wherein the layer configured to preclude substantially all light passing through the photoresponsive component from reaching the substrate comprises a metal silicide. 
   
   
       30 . The device of  claim 28 , wherein the substrate comprises at least one circuit component, and wherein the layer is further configured to preclude substantially all light passing through the photoresponsive component from reaching the at least one circuit component. 
   
   
       31 . An apparatus comprising:
 a semiconductor substrate comprising at least one circuit component;   a semiconductor photoresponsive component overlying at least part of the substrate, the photoresponsive component having a first surface configured to receive incident radiation, the first surface having a first periphery; and   a metal silicide layer disposed at least partially between the photoresponsive component and the at least one circuit component, the metal silicide layer having a second surface configured to receive incident radiation passing through the photoresponsive component, the second surface having a second periphery greater than the first periphery.