本篇研究利用簡便的溶液製程，以旋轉塗佈法沉積高熵高介電常數的(Al, Ti, V, Zr, Hf)Ox薄膜，並製備成金氧半電容(MOS)以及金氧半場效電晶體(MOSFET)以研究其電性及熱穩定性。透過測試各式各樣的加溫製程參數，包含旋轉塗佈後的烤乾溫度、烤乾後的退火溫度以及混合氣退火(FGA)的溫度和製程氣壓，高熵氧化物(HEO)薄膜性質得到最佳化。其MOS元件在電容—電壓(C-V)及電流—電壓(I-V)量測中表現出優異的電性，並經計算得出在1 kHz之下擁有約為33的介電常數。透過XPS分析，得知薄膜的表面的組成元素及其價態(Al3+, Ti4+, V4+/V5+, Zr4+, Hf4+, 以及O2-)。HEO薄膜的熱穩定性則藉由 900 °C的5秒快速熱退火處理(RTA)來進行探討。經過RTA的HEO薄膜仍保持近乎非晶質的狀態，並且再經過FGA後表現出改善的C-V特性以及可接受的漏電流值。而HEO製備而成MOSFET元件，展現出1.75 V的閾值電壓、102的開關電流比、149 cm2/Vs的飽和遷移率以及214 mV/dec的亞閾值擺幅。

This study reports the fabrication of high-k high-entropy (Al, Ti, V, Zr, Hf)Ox films through spin-coating and the study of electrical properties and thermal stability of resulting advanced MOS and MOSFET devices. Various annealing conditions were studied, including drying temperature after spin-coating, annealing temperature after drying, and forming gas annealing (FGA) profiles, to optimize the high-entropy oxide (HEO) films. The favorable HEO-film-resulting MOS devices exhibited excellent capacitance-voltage (C-V) and current-voltage (I-V) characteristics; the deduced dielectric constant at 1 kHZ was approximately 33. The valence states of all the constitutive elements (i.e., Al3+, Ti4+, V4+/V5+, Zr4+, Hf4+, and O2-) were determined through XPS. The HEO films were further subjected to rapid thermal annealing (RTA) at 900 °C for 5 s to affirm their thermal stability. The sample after both RTA and FGA exhibited the robust C-V and reasonably low I-V characteristics. The threshold voltage of 1.75 V, on/off ratio of 102, saturated mobility of 149 cm2/Vs, and subthreshold swing of 214 mV/dec was obtained for the resulting MOSFETs.

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