Polished polyimide substrate

Abstract

Polymer substrates, in particular polyimide substrates, and polymer laminates for optical applications are described. Polyimide substrates are polished on one or both sides depending on their thickness, and single-layer or multi-layer waveguide structures are deposited on the polished polyimide substrates. Optical waveguide devices are machined by laser ablation using a combination of IR and UV lasers. A waveguide-fiber coupler with a laser-machined groove for retaining the fiber is also disclosed.

What is claimed is:  
     
         100 . A substrate for a circuit structure comprising a planar substrate mass of polyimide material having a first side and a second side, said first side being polished to a surface smoothness between about 1 μinch and 20 μinch, capable of receiving a circuit structure, wherein said second side is polished, further comprising a first polymer layer applied to said first polished side of said planar substrate mass.