Optical fiber alignment device

Abstract

A fiber alignment or “fiberposer” device enables the passive alignment of one or more optical fibers to a photonic integrated circuit (PIC) device using mating hard-stop features etched into the two devices. Accordingly, fiber grooves can be provide separate from the electrical and optical elements, and attached to the PIC with sub-micron accuracy. Fiberposers may also include a hermetic seal for a laser or other device on the PIC. All of these features significantly reduce the typical cost of an actively aligned optical device sealed in an hermetic package.

We claim: 
     
         1 . An optical assembly comprising:
 a fiber alignment device for mounting on a photonic integrated chip (PIC), which includes first alignment features, a component, and an optical waveguide with a waveguide core, the optical fiber alignment device comprising:   a fiber-mounting section, including a groove for receiving a portion of an optical fiber, configured to align a fiber core of the optical fiber with the waveguide core of the optical waveguide;   a PIC mounting section forming an end point of the groove, and including a cavity for receiving the component; and   second alignment features for abutting the first alignment features.   
     
     
         2 . The assembly according to  claim 1 , wherein the second alignment features comprise pillars configured for abutting hard stops on the PIC. 
     
     
         3 . The assembly according to  claim 2 , wherein the second alignment features comprise an array of pillars configured to extend on each side of the component. 
     
     
         4 . The assembly according to  claim 1 , further comprising a trough extending from an outer free end of the groove for collecting excess material used to bond the optical fiber in the groove. 
     
     
         5 . The assembly according to  claim 1 , further comprising a ground connection in the cavity for grounding the component to the fiber alignment device. 
     
     
         6 . The assembly according to  claim 1 , further comprising a hermetically sealable material surrounding an opening to the cavity for hermetically sealing the component within the cavity. 
     
     
         7 . The assembly according to  claim 1 , further comprising the PIC, which includes the first alignment features, the component, and the optical waveguide with the waveguide core. 
     
     
         8 . The assembly according to  claim 7 , wherein the first alignment features comprise openings in the PIC down to corresponding hard stops; and wherein the second alignment features comprise pillars extending from the optical fiber alignment device into the openings abutting the corresponding hard stops. 
     
     
         9 . The assembly according to  claim 8 , wherein the hard stop comprises the optical waveguide layer. 
     
     
         10 . The assembly according to  claim 8 , wherein each opening is substantially wider than each corresponding pillar, enabling horizontal (X-Y) alignment. 
     
     
         11 . The assembly according to  claim 7 , further comprising:
 first bonding pads mounted in recesses in the PIC mounting section; and   second bonding pads on the PIC for bonding with the first bonding pads via a bonding material disposed therebetween; and   whereby excess adhesive material is trapped in the recesses during and after assembly.   
     
     
         12 . The assembly according to  claim 7 , wherein the component comprises an array of lasers;
 wherein the PIC includes a plurality of waveguides in the waveguide layer optically coupled to the array of lasers; and   wherein the fiber mounting section includes a plurality of additional grooves for a plurality of additional optical fibers optically aligned with the plurality of waveguides.