Design of low insertion loss, single-mode polymeric waveguides

本发明提供了有机光波导器件，它是通过光刻法形成的并且采用了传播损耗低的聚合物材料。光波导具有基底(2)；处于基底表面上的聚合物缓冲体层(4)；处于缓冲体层表面上薄的聚合物下包覆体层(6)；处于下包覆体层表面上的透光性芯体聚合物图案(8)，以及处于芯体顶表面和芯体侧壁上以及一部分下包覆体层上的聚合物上包覆体层(10)，下包覆体层的厚度是芯体厚度的约10％～约50％。芯体的折射率n#-[c]大于上包覆体层的折射率n#-[o]，而且也大于下包覆体层的折射率n#-[u]；其中Δn＝n#-[c]-n#-[o]，并且其中n#-[c]与缓冲体折射率n#-[b]之差至少为Δn的约1.5倍。 The invention provides organic optical waveguide devices which are lithographically formed and employ polymeric materials having low propagation loss. An optical waveguide has a substrate; a polymeric buffer layer on a surface of the substrate; a thin, polymeric undercladding layer on a surface of the buffer layer; a pattern of a light-transmissive, polymeric core on the surface of the undercladding layer; and a polymeric overcladding layer on a top surface of the core and on sidewalls of the core and on a portion of the undercladding layer; the undercladding layer having a thickness of from about 10 percent to about 50 percent a thickness of the core. The core has an index of refraction nc which is greater than an index of refraction of the overcladding layer no and also greater than an index of refraction of the undercladding layer nu; wherein DELTAn=nc-no, and wherein the difference between nc and the index of refraction of the buffer nb is at least about 1.5 times DELTAn.