Facility Agriculture: Energy Saving and SterilizationDepartment of Materials Science Engineering / Wuu, Dong-Sing / Distinguished Professor
設施農業:節能栽培與滅菌【材料科學與工程學系/武東星特聘教授】
 
論文篇名 英文:Impact of thermal-induced sapphire substrate erosion on material and photodetector characteristics of sputtered Ga2O3 films
中文:熱引起藍寶石基板腐蝕對濺鍍之氧化鎵薄膜於材料和光感測器特性的影響
期刊名稱 JOURNAL OF ALLOYS AND COMPOUNDS
發表年份,卷數,起迄頁數 2020, 823, 153755
作者 Li, Hui; Yuan, Shuo-Huang; Huang, Tsun-Min; Chen, Hsuan-Jen; Lu, Fu-Hsing; Zhang, Sam; Wuu, Dong-Sing(武東星)*
DOI 10.1016/j.jallcom.2020.153755
中文摘要 透過結合濺鍍製程及後退火製程,在c面藍寶石基板上沉積單晶β相氧化鎵(β- Ga2O3)膜。發現高熱導致藍寶石襯底腐蝕對濺射的β-Ga2O3薄膜材料特性的影響。高溫退火爐管和快速熱退火(RTA)都在空氣環境中進行後退火處理。在退火過程後,所有沉積的薄膜結構從非晶態轉變為單斜晶結構,而穿透率在可見光可達80%。同時,在β-Ga2O3/藍寶石結構中,特別是經過高溫退火爐管退火之試片,可觀察到由熱能引起的相互擴散現象。即使高溫熱處理可以提高Ga2O3薄膜的結晶度,但由於熱誘導的鋁(Al)擴散問題,在800oC以上退火的試片中仍觀察到光響應下降。因此提出了透過濺鍍製程於藍寶石基板上之薄膜會互相擴散之機制,並分析其現象對材料和光電感測器特性的影響。最後,於800oC-RTA處理的Ga2O3薄膜,光/暗電流比為1.78×105,響應度為0.553 A/W(在5 V偏壓下),可獲得最佳的金屬-半導體-金屬光電探測器性能。
英文摘要 Monoclinic β-phase gallium oxide (β-Ga2O3) films were deposited on c-plane sapphire substrates using a combination of sputtering and post annealing processes. The effect of thermal-induced sapphire substrate erosion on material characteristics of sputtered β-Ga2O3 film has been investigated. Both the furnace and rapid thermal annealing (RTA) were performed in the air ambient for the post thermal treatments. After the annealing process, all the deposited films transformed from amorphous to monoclinic crystalline structure with excellent transmittance above 80% in the visible region. Meanwhile, a thermal-induced interdiffusion phenomenon has been observed in β-Ga2O3/sapphire architecture, particularly for furnace-annealed samples. Even though high-temperature post thermal treatments can enhance the crystallinity of the Ga2O3 films continuously, a degraded photodetector performance is observed for the samples annealed above 800 oC due to the thermal-induced aluminum (Al) diffusion issue. The interdiffusion mechanism for the sputtered Ga2O3-on-sapphire films is proposed and its effects on material and photodetector characteristics are elucidated. An optimum metal-semiconductor-metal photodetector performance is achieved for the 800 oC -RTA-treated Ga2O3 sample with the photo/dark current ratio of 1.78 × 105 and responsivity of 0.553 A/W (at 5 V bias).