Optical module including silicon photonics chip and coupler chip

Abstract

An optical module includes a waveguide interconnect that transports light signals; a Silicon Photonics chip that modulates the light signals, detects the light signals, or both modulates and detects the light signals; a coupler chip attached to the Silicon Photonics chip and the waveguide interconnect so that the light signals are transported along a light path between the Silicon Photonics chip and the waveguide interconnect; and one of the Silicon Photonics chip and the coupler chip includes first, second, and third alignment protrusions. The other of the coupler chip and the Silicon Photonics chip includes a point contact, a linear contact, and a planar contact. The point contact provides no movement for the first alignment protrusion. The linear contact provides linear movement for the second alignment protrusion. The planar contact provides planar movement for the third alignment protrusion.

What is claimed is: 
     
         1 . An optical module comprising:
 a waveguide interconnect that transports light signals;   a Silicon Photonics chip that modulates the light signals, detects the light signals, or both modulates and detects the light signals;   a coupler chip attached to the Silicon Photonics chip and the waveguide interconnect so that the light signals are transported along a light path between the Silicon Photonics chip and the waveguide interconnect; and   one of the Silicon Photonics chip and the coupler chip includes first, second, and third alignment protrusions;   the other of the coupler chip and the Silicon Photonics chip includes:
 a point contact; 
 a linear contact; and 
 a planar contact; 
   the point contact provides no movement for the first alignment protrusion;   the linear contact provides linear movement for the second alignment protrusion;   the planar contact provides planar movement for the third alignment protrusion.   
     
     
         2 . The optical module of  claim 1 , wherein the first, second, and third alignment protrusions are spherical balls made of glass that are located in inverted pyramids provided in the one of the Silicon Photonics chip and the coupler chip. 
     
     
         3 . The optical module of  claim 1 , further comprising a spacer attached to the Silicon Photonics chip. 
     
     
         4 . The optical module of  claim 3 , wherein the spacer and the Silicon Photonics chip are anodically bonded together. 
     
     
         5 . The optical module of  claim 1 , wherein a cross-sectional size of a beam defined by the light signals is largest at an interface between the Silicon Photonics chip and the coupler chip. 
     
     
         6 . The optical module of  claim 1 , wherein a cross-sectional size of a beam defined by the light signals increases initially along the light path and then decreases along the light path. 
     
     
         7 . The optical module of  claim 1 , wherein at least one of the Silicon Photonics chip and the coupler chip includes a focusing element. 
     
     
         8 . The optical module of  claim 7 , wherein the focusing element is a collimating lens. 
     
     
         9 . The optical module of  claim 1 , wherein the waveguide interconnect is detachable from the optical module. 
     
     
         10 . The optical module of  claim 1 , wherein the waveguide interconnect includes a spot-size-converter region. 
     
     
         11 . The optical module of  claim 1 , wherein the Silicon Photonics chip includes a photodetector mounted on a surface of the Silicon Photonics chip. 
     
     
         12 . The optical module of  claim 1 , wherein the Silicon Photonics chip and the coupler chip include fiducials on surfaces that do not face each other. 
     
     
         13 . A transceiver comprising:
 the optical module of  claim 1 ; and   a printed circuit board; wherein   the Silicon Photonics chip is connected to the printed circuit board.   
     
     
         14 . The transceiver of  claim 13 , further comprising a housing enclosing the Silicon Photonics chip and the coupler chip. 
     
     
         15 . The transceiver of  claim 14 , further comprising a latch that secures the coupler chip in the housing; wherein
 the coupler chip is detachable from the housing by unlatching the latch.   
     
     
         16 . An optical module comprising:
 a Silicon Photonics chip that includes a waveguide that transports light signals; and   a coupler chip attached to the Silicon Photonics chip so that the light signals are transported along a light path between the Silicon Photonics chip and the coupler chip; wherein   the coupler chip changes a cross-sectional size of a beam defined by the light signals; and   the coupler chip includes a multiplexer, a demultiplexer, or both a multiplexer and a demultiplexer.   
     
     
         17 . The optical module of  claim 16 , wherein the multiplexer, the demultiplexer, or both the multiplexer and the demultiplexer include an Echelle grating, an arrayed waveguide grating, a direction coupler, a dichroic filter, or a resonant interference filter. 
     
     
         18 . The optical module of  claim 16 , wherein the cross-sectional size of the beam is largest at an interface between the Silicon Photonics chip and the coupler chip. 
     
     
         19 . The optical module of  claim 16 , wherein the cross-sectional size of the beam increases initially along the light path and then decreases along the light path. 
     
     
         20 . The optical module of  claim 16 , wherein a photodetector is surface mounted to the Silicon Photonics chip. 
     
     
         21 . The optical module of  claim 16 , wherein a photodetector is included within the Silicon Photonics chip. 
     
     
         22 . The optical module of  claim 16 , wherein a light source is included within the Silicon Photonics chip. 
     
     
         23 . The optical module of  claim 16 , further comprising a light source located outside of the Silicon Photonics chip; wherein
 light from the light source is supplied to the Silicon Photonics chip.   
     
     
         24 . The optical module of  claim 16 , wherein the Silicon Photonics chip includes a via in the light path. 
     
     
         25 . The optical module of  claim 16 , wherein the Silicon Photonics chip and the coupler chip are anodically bonded to each other. 
     
     
         26 . An optical module comprising:
 a Silicon Photonics chip that includes a waveguide that transports light signals; and   a coupler chip attached to the Silicon Photonics chip so that the light signals are transported along a light path between the Silicon Photonics chip and the coupler chip; wherein   the light path includes a first surface of the coupler chip and a second surface of the coupler chip; and   a cross-sectional size of a beam defined by the light signals is different at the first and second surfaces.   
     
     
         27 . The optical module of  claim 26 , wherein at least one of the Silicon Photonics chip and the coupler chip includes a focusing element. 
     
     
         28 . The optical module of  claim 27 , wherein the focusing element is a collimating lens. 
     
     
         29 . A method of aligning two substrates comprising:
 providing a first substrate with a first fiducial and a second substrate with a second fiducial, the first and second fiducials are located on surfaces of the first and second substrates that are not facing each other;   providing first and second cameras that are opposed to each other such that the first camera views the first fiducial and the second camera views the second fiducial; and   aligning the first and second substrates by aligning the first and second fiducials using the first and second cameras.   
     
     
         30 . The optical module of  claim 1 , wherein the coupler chip includes a borosilicate glass having a coefficient of thermal expansion substantially similar to silicon. 
     
     
         31 . The optical module of  claim 16 , wherein the coupler chip includes a borosilicate glass having a coefficient of thermal expansion substantially similar to silicon. 
     
     
         32 . The optical module of  claim 26 , wherein the coupler chip includes a borosilicate glass having a coefficient of thermal expansion substantially similar to silicon.