氫離子感測電極的電化學機制及五氧化二鉭與氧化銥薄膜之研究

Abstract

離子感應場效電晶體（Ion-Sensitive Field Effect Transistor）最早由P. Bergveld在1970初期提出後，材料改良、電極的微小化與結構的改善等，都相繼廣泛的討論。隨著固態電子工程建構技術的進步，離子感應場效電晶體已經可以做到次微米大小的程度。 在白金電極上，先後濺鍍氧化銥薄膜與五氧化二鉭薄膜，製作成氫離子感測電極。五氧化二鉭薄膜對氫離子具有單一選擇性，將五氧化二鉭完全覆蓋於氧化銥薄膜上，使得氧化銥薄膜只能對氫離子與電子進行氧化還原反應，改變自身的費米能階。所製作出來的氫離子感測元件，可在室溫與常壓下工作，並改進氧化銥薄膜易被其他氧化還原物質影響的缺點，且具有良好的電位穩定性和再現性等優點。

The ion-sensitive field effect transistor was put forward by P. Bergveld in 1970. And improvement of materials and structures has been researched extensively. With the progress of electronic engineering of solid states and thin films technology, ion-sensitive field effect transistor could be reached the submicron degree. The pH-sensing device was be constructed by RF sputtered IrO2 and Ta2O5 films on platinum electrode. It needs Ta2O5 to sort out H+ in order to maintain steady potential difference. Ta2O5 covers IrO2 thoroughly and prevents IrO2/Ir[OH]3 from oxidation by O2. Our sensor could work well under the room temperature and normal atmosphere. We still overcame the problem of that IrO2 was disturbed by O2 and possessed stable potential difference and reproducibility.