20 KB383 KB17 KB200020262000Koller, LidijaPožun, KarolPraček, Borutletnik:34številka:55 stranistr. 311-315ISSN:1580-2949COBISSID:237738URN:URN:NBN:SI:doc-ZKKKCWVTslInštitut za kovinske materiale in tehnologijeMateriali in tehnologijepolimerirelativna vlažnostsenzorjizamreževanjeVpliv stopnje zamreženja na karakteristike kapacitivnega polimernega senzorja relativne vlažnosti zraka| The effect of the degree of cross-linking on the characteristics of a polymer capacitive-type sensor|A cross-linked polymer film was prepared on a glass substrate by using the photo-irradiation technique and evaluated as a capacity-type humidity sensor. The sensing characteristic were considerably affected by the degree of cross-linking in the film. The sensitivity was enhanced with up to 95% cross-linking, beyond this the sensitivity decreased. This has been explained by the variation in the ability to absorb water with the degree of cross-linking. Similar behaviour was observed for the vapours on the adsorption of the sandwich-cermet (insulator-gold-insulator) type devices prepared with the thin gold metal film as an upper electrode which was deposited by vacuum evaporation. The behaviour was explained by the segment motion of the main chain and the side chain. If the cross-linking reaction proceeds and the film becomes rigid, the segment motion of the main chain is depresssed. As a result, the value of the dielectric loss decreasesVpliv obsevanja polimera z UV-žarki na stekleni podlagi opazujemo po spremembi dielektrične konstante in drugih znanih karakteristik senzorja relativne vlažnosti zraka. Stopnja polimerizacije močno vpliva na občutljivost senzorja pri merjenju spremembe vlage v okolju. Občutljivost senzorja se lahko poveča do 95%, nad to vrednostjo pa njegova občutljivost hitro pade, kljub daljšemu času osvetlitve z UV žarki. To si razlagamo tako, da je količina absorbirane vodne pare odvisna od stopnje polimerizacije. Podoben vpliv povečanja absorpcije vodne pare iz zraka smo opazili pri senzorski strukturi, kjer smo kot zgornjo elektrodo naparili sendvič strukturo SiO-zlato-SiO. Poznano je, da se delež dielektrične obnove poveča s premiki nekaterih segmentov v glavni molekulski verigi in enako velja za premike v stranskih verigah. S povečanjem časa izpostavitve polimera UV-svetlobi postane polimer bolj trd, gibljivost segmentov v glavni molekulski verigi pa se počasi ustavi. Rezultat tega je zmanjšanje dielektričnih izgubTEXTznanstveno časopisjejournalsSlovenian National E-content AggregatorNational and University Library of SloveniaInštitut za kovinske materiale in tehnologije