Waveguide structures by ion irradiation of polymeric materials

To fulfil these requirements two problems had to be solved masking the structures 7 pm wide and creating symmetric waveguide layers. For technical applications of a device the coupling between the fiber and the waveguide de- 

Two possible methods of developing structures with the required dimensions are outlined in Fig. 22 (a) irradiation through a fineestanding mask, (b) embossing of the structure directly into the polymeric substrate. 

Both methods will be described briefly and the problems discussed. Manufacture of a freestanding ma.sk is described in more detail in [I60, so only a short summary of the important features is given here. 

Rapid change of substrates with a specially developed substrate holder would be necessary for a high production rate. One disadvantage which appeared during the experiments was the sensitivity of the mask to temperature 

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