本篇論文利用氮化鋁鎵/氮化鎵高速電子遷移率電晶體以及改變閘極金屬之特性製作出氯離子以及壓力感測器。 在氯離子感測器方面，我們利用陽極氧化法改質閘極材料，在閘極上鍍上一層氯化銀。當此感應器處於有氯離子濃度之液體時，其表面電會會隨之改變，使得氮化鋁鎵/氮化鎵高速電子遷移率電晶體中的二微電子氣體之濃度會隨之改變而影響此電元件之導電性，我們量得其偵測極限為1E-8M. 在壓力感應器方面，我們利用一具有壓電特性之聚合物材料(PVDF)作為改質閘極之材料，因其具有電偶極子在其中，所已經過極化後，其為一極佳的壓電材料。當此材料受到壓力時，其電偶極子的距離會被壓縮而減少，進而影響氮化鋁鎵/氮化鎵高速電子遷移率電晶體中的二微電子氣體之濃度以及元件之導電性。我們測的期偵測極限為1psig. We demonstrated two kind of sensor, including one liquid and one gas sensor, using AlGaN/GaN HEMT. For Chloride ion sensor, we use AgCl as modified gate material, which was grown by anodization. When the AgCl gate encountered some chloride ion in the liquid, the electrical potential of AgCl will changed and induced some excess charge in the 2-DEG in AlGaN/GaN HEMT. This will increase the Ids in the HEMT. The limit of detection was 1E-8M. For pressure sensor, we use PVDF as modified gate material, which is a polarized polymer. After high voltage polarization, it will show good polarization. when the PVDF encountered some gas pressure, the distance of the dipole moment inside will change and induced some concentration difference of the 2-DEG in the HEMT. this will change the Ids and the limit of detection was 1psig
