Silicon microlens on V-groove platform for low-cost and high-performance optical modules

We succeeded in developing the prototype Si microlens that is applicable to the surface mount technology (SMT) using Si V-groove substrate. The diameter of the fabricated Si microlens was identical to that of SMF. The Si microlens was successfully picked and placed on the V-groove substrate, realizing automatic alignment between the microlens and SMF by sharing the same V-groove. The microlens has an ability to achieve the coupling efficiency as high as -3.0 dB between DFB-LD and SMF. The designed microlens can realize collimated beam, so that any functional elements such as an isolator are integrated on the Si V-groove substrate, making the SMT with a Si V-groove a universal platform suitable for mass-producible low-cost and high-performance optical modules.