Optical device with precoated underfill

Abstract

A method for fabricating an optical multi-chip module (MCM) includes temporarily curing an underfill material on a chip including an optical device to prevent flow of the underfill material. The chip is flip-chip mounted on a waveguide module having a mirror for directing light to or from the chip, wherein the underfill material is disposed between the chip and the waveguide module. The underfill material is cured to adhere the chip to the waveguide module.

1 . An optical multi-chip module (MCM), comprising:
 a waveguide module having a cavity with a mirror, the mirror being configured to direct light into or from a waveguide formed in the waveguide module;   a chip flip-chip mounted on the waveguide module to have a light input or output formed on the chip aligned with the mirror; and   a reflowable underfill material disposed between the chip and the waveguide module to adhere the chip to the waveguide module without filling the cavity.   
     
     
         2 . The MCM as recited in  claim 1 , wherein the underfill material includes a cyclotene resin. 
     
     
         3 . The MCM as recited in  claim 1 , wherein electrodes on the chip are soldered to contacts on the waveguide module. 
     
     
         4 . The MCM as recited in  claim 1 , wherein the underfill material forms a gap distance between the chip and the waveguide module which is provided by a solid form of the underfill material before flip-chip mounting the chip on the waveguide module. 
     
     
         5 . The MCM as recited in  claim 1 , wherein the underfill material includes a semi-curable and reflowable resin. 
     
     
         6 . An optical multi-chip module (MCM), comprising:
 a waveguide module having a cavity with a mirror, the mirror being configured to direct light into or from a waveguide formed in the waveguide module;   a chip flip-chip mounted on the waveguide module to have a light input or output formed on the chip aligned with the mirror; and   a reflowable underfill material disposed between the chip and the waveguide module to adhere the chip to the waveguide module without filling the cavity; and   one or more electrodes on the chip soldered to contacts on the waveguide module.   
     
     
         7 . The MCM as recited in  claim 6 , wherein the underfill material includes a cyclotene resin. 
     
     
         8 . The MCM as recited in  claim 6 , wherein the underfill material forms a gap distance between the chip and the waveguide module which is provided by a solid form of the underfill material before flip-chip mounting the chip on the waveguide module. 
     
     
         9 . The MCM as recited in  claim 6 , wherein the underfill material includes a semi-curable and reflowable resin. 
     
     
         10 . An optical multi-chip module (MCM), comprising:
 a waveguide module having a cavity with a mirror;   a chip flip-chip mounted on the waveguide module to have a light input or output formed on the chip aligned with the mirror; and   a reflowable cyclotene resin disposed between the chip and the waveguide module to adhere the chip to the waveguide module without filling the cavity.   
     
     
         11 . The MCM as recited in  claim 10 , wherein the mirror being configured to direct light into or from a waveguide formed in the waveguide module. 
     
     
         12 . The MCM as recited in  claim 10 , wherein electrodes on the chip are soldered to contacts on the waveguide module. 
     
     
         13 . The MCM as recited in  claim 10 , wherein the cyclotene resin forms a gap distance between the chip and the waveguide module which is provided by a solid form of the cyclotene resin before flip-chip mounting the chip on the waveguide module.