argon and trifluoromethane ar chf 3 under reactive ion etching conditions at 120 watts for sufficient time to allow the etching rates to be determined for comparative purposes a similar substrate was vapour coated with 1 2 u03bcm of poly ethyl 2 cyanoacrylate peca and the plasma etching rate of this resist relative to sio 2 was also measured under similar conditions the results obtained were as follows ______________________________________ resist etch sio sub 2 etch resist sio sub 2 etchresist rate u00e5 min sup 1 rate u00e5 min sup 1 rate ratio______________________________________ptsca 106 312 0 34peca 180 292 0 62______________________________________ these results demonstrate a significant improvement in the etch resistance of the silicon containing cyanoacrylate resist compared to a similar photoresist which does not contain silicon the etch rate of ptsca resist in an oxygen plasma was also determined in a related experiment in this case the etch resistance was compared not only to peca but also to a number of commercially available photoresist products the results obtained are as follows ______________________________________ etch rate relative etchresist o sub 2 plasma u00e5 min sup 1 resistance to peca______________________________________ptsca 162 30 09peca 5000 1az 4330 hoechst 2814 1 8microposit 2400 shipley 2172 2.