질산망간의 건식-복사열분해 온도에 따른 탄탈륨 콘덴서 특성 연구

Abstract

The characteristics of manganese dioxide(MnO2) layer for the solid electrolyte of tantalum condenser formed in accordance with its pyrolysis temperature by a dry-radiational pyrolysis instead of a traditional wet-convectional pyrolysis of manganese nitrate was studied. As a result of TG/DSC analysis, manganese nitrate was started to be pyrolyzed at the temperature range from 180 to 230 oC through dehydration process and was transformed into MnO2 single phase at the temperature range from 230 to 250 oC. Tantalum pellets were pyrolyzed at intervals of 20 oC from 200 to 300 oC in a radiational furnace on the basis of TG/DSC results and then re-anodized. There were nothing particular physical problems on the dielectric layer after pyrolysis. The condensers pyrolyzed between 240 and 260 oC recorded better properties like as a higher withstanding voltage and a lower leakage current. According to the impedance and SEM analysis results on the tantalum condenser pyrolytically decomposed 3 times with 30 wt% manganese nitrate aqueous solution, it was verified that uniform and stable manganese dioxide layers were formed by a dry-radiational pyrolysis and its properties like as capacitance, dissipation factor, internal resistance and frequency dependency were improved with the increase of the pyrolysis temperature