本文關(guān)鍵詞： 陽極氧化 電子束蒸發(fā) 絕緣層 Mg-Al合金薄膜　出處：《深圳大學(xué)》2017年碩士論文　論文類型：學(xué)位論文

【摘要】：顯示屏是人機交互的界面,越來越成為人們工作生活中不可或缺的角色。非晶氧化物半導(dǎo)體薄膜晶體管(AOS-TFT)具有載流子遷移率高(1~100 cm2V-1s-1)、薄膜均勻性好、工藝溫度相對較低、薄膜對可見光透明、與現(xiàn)有a-Si TFT制備工藝兼容等優(yōu)點,是下一代顯示技術(shù)的有力競爭者。但AOS-TFT難免使用高真空、高能量等昂貴真空設(shè)備進行氧化物薄膜蒸鍍,一方面使得氧化物薄膜的氧空位難以控制,另一方面不利于TFT的低溫制備,無法滿足電子紙、透明顯示等新型顯示器件的發(fā)展需求。陽極氧化法設(shè)備簡單,成本低廉,能實現(xiàn)TFT的低溫制備,本文首次探索陽極氧化Mg-Al合金實現(xiàn)復(fù)合氧化物薄膜的制備,并對其結(jié)構(gòu)、絕緣性能等進行了研究,主要工作和研究結(jié)果如下:1.對比電子束蒸發(fā)和磁控濺射蒸鍍方式,發(fā)現(xiàn)單源電子束蒸發(fā)和磁控濺射難以控制薄膜的Mg、Al比例,采用Mg、Al金屬兩種靶材,通過雙源電子束蒸發(fā)可以很好控制薄膜的成分比例。2.經(jīng)合金薄膜的EDS、SEM等表征,其結(jié)果表明,在優(yōu)化電子束蒸發(fā)的束流大小、靶材、基板溫度的工藝參數(shù)下,通過調(diào)整束流能夠得到期望比例的Mg-Al合金薄膜,合適的束流和高純Mg粒、Al粒靶材以及180℃的基板溫度,可以提高薄膜的質(zhì)量,得到表面形貌平整、致密的合金薄膜。3.在陽極氧化方面,首先通過鋁膜的陽極氧化制備氧化鋁簿膜,并獲得了性能較好的氧化鋁絕緣層,以此驗證金屬陽極氧化制備氧化物薄膜的可行性。在此基礎(chǔ)上,進行了通過陽極氧化Mg-Al合金薄膜制備Mg-Al復(fù)合氧化物薄膜的研究。研究表明,陽極氧化中恒定電流大小、恒定電壓大小、恒壓時長以及Mg-Al合金薄膜成分比例均對氧化膜的絕緣性能有影響。采用合適比例的Mg-Al合金薄膜和2mA-85V、3mA-85V的恒流恒壓參數(shù)可以得到質(zhì)量較高的氧化物薄膜,適當(dāng)延長恒壓氧化的時間可進一步減少薄膜的缺陷,降低薄膜的漏電流。4.薄膜經(jīng)過退火處理,可以降低薄膜的粗糙度和缺陷,進一步降低漏電流。綜合優(yōu)化工藝參數(shù),陽極氧化薄膜的漏電流為10-4mA/cm2量級,擊穿電壓約為20V,相對介電常數(shù)8.35,將氧化膜作為TFT的絕緣層,器件表現(xiàn)出一定的場控效應(yīng)。
[Abstract]:The display screen is the interface of human-computer interaction. Amorphous oxide semiconductor thin film transistors (AOS-TFTs) have a high carrier mobility of 100 cm2V-1s-1). The film has the advantages of good uniformity, relatively low process temperature, transparent to visible light and compatible with the existing a-Si TFT fabrication process. However, AOS-TFT inevitably uses high vacuum, high energy and other expensive vacuum equipment for oxide film evaporation. On the one hand, the oxygen vacancy of oxide film is difficult to control. On the other hand, it is not conducive to the preparation of TFT at low temperature and can not meet the development needs of new display devices such as electronic paper, transparent display, etc. The anodizing process is simple in equipment and low in cost, and can realize the low temperature preparation of TFT. In this paper, the preparation of composite oxide films by anodic oxidation of Mg-Al alloy was investigated for the first time, and its structure and insulation properties were studied. The main work and results are as follows: 1. Compared with the methods of electron beam evaporation and magnetron sputtering evaporation, it is found that the ratio of mg / Al in single source electron beam evaporation and magnetron sputtering is difficult to control. The composition ratio of Al metal target can be well controlled by double source electron beam evaporation. The results show that the composition ratio of Al metal target can be well controlled by EDS- SEM of the alloy film. The desired ratio of Mg-Al alloy film, appropriate beam current and high purity mg particles can be obtained by adjusting the beam current under the optimized parameters of beam size, target material and substrate temperature of electron beam evaporation. Al particle target and substrate temperature of 180 鈩，

本文編號：1452041