Passive alignment of single-mode fibers to integrated polymer waveguide structures utilizing a single-mask process

A fabrication process for high precision passive fiber chip coupling is pre sented. The difficulties of structuring highly nonplanar surfaces were solv ed by using an electrophoretic photoresist and introducing additional struc tures to prevent wide holes. The method involves only a single lithographic step for structuring the polymer waveguide and fiber aligning structures i n Si and thereby minimizing the horizontal displacement. The loss due to fi ber displacement is about 0.7 dB per front face.