本論文以超音波噴塗熱裂解法研製非晶型氧化銦錫鋅全透明薄膜電晶體，超音波噴塗熱裂解法具備低成本、非真空、高沉積速率之優勢，且能沉積出高品質及良好均勻度的薄膜，本次實驗利用此方法沉積氧化銦錫鋅主動層和氧化鋁介電層。非晶氧化銦錫鋅為極具潛力的材料由於與非晶氧化銦鎵鋅相比擁有更高的遷移率和穩定性。為了提升元件整體透光度使其平面顯示器中有更佳的應用，我們致力於製備全透明薄膜電晶體，在電極上，我們選用了三種透明導電氧化物:氧化鋅鋁、氧化鋅鎵和氧化銦錫，並分別探討在不同射頻濺鍍功率下，對於薄膜電晶體之電性影響，分別找出最佳化的濺鍍功率，並且比較之。
我們研究出元件搭配最佳化的氧化銦錫作為電極有最高的電子遷移率。在線性區轉換特性有著開關電流比~109、次臨界擺幅123 mV/dec、場效電子遷移率38.95 cm2/V-s和臨界電壓2.52"V" ，較高的電子遷移率歸因於最佳化的氧化銦錫有著最低的電阻率。元件搭配最佳化的氧化鋅鎵和氧化鋅鋁分別有著場效電子遷移率9.29 cm2/V-s和7.75 cm2/V-s，開關電流比皆為~108，元件電性主要受限於最佳化的氧化鋅鎵和氧化鋅鋁電阻率與常見之透明導電氧化物相比仍較大，因此影響了元件在導通電流的表現。
在薄膜電晶體穩定性之測試當中，閘極負偏壓照光測試常常被用來作為穩定度的指標，造成閘極負偏壓照光穩定性變化的主要原因來自照光後產生的電洞被侷限在介電層或通道層與介電層間，以及主動層中的電中性氧空缺照光後產生的電子被侷限在通道表面。在本次實驗中，我們用閘極加偏壓-5伏特以及持續照光3000秒，分別測試元件搭配最佳化電極氧化鋅鎵、氧化鋅鋁和氧化銦錫的穩定度，偏移量分別為-0.43 V、-0.43 V以及-0.57 V，元件搭配最佳化電極氧化鋅鎵、氧化鋅鋁有著比搭配最佳化氧化銦錫較佳的穩定性，我們推測氧化銦錫的能隙相較於氧化鋅鎵與氧化鋅鋁小，因此對於照光比較敏感，而影響整體元件在照光穩定度的表現。
在本論文中，成功以超音波噴塗熱裂解法製備非晶型氧化銦錫鋅全透明薄膜電晶體，此沉積薄膜方法在製程時間以及成本皆相當具有優勢。在元件電性表現方面擁有高透光度、高電子遷移率、高穩定性等優點，因此下個世代平面顯示器產業需要更大面積以及更高解析度的應用中，非晶型氧化銦錫鋅為極具潛力之材料，有望在未來取代市面上常見之非晶型氧化銦鎵鋅。

In this thesis, we fabricated amorphous ITZO all transparent thin-film transistors (TTFTs) by Ultrasonic Spray Pyrolysis Deposition (USPD). USPD has the advantages of low cost, non-vacuum, high deposition rates, and can deposit thin films with good quality and good uniformity. In this work, we deposited the ITZO channel layer and the Al2O3 dielectric layer by USPD. Amorphous ITZO is a highly promising material mainly because of its higher mobility and stability compared to amorphous IGZO. In order to improve the transmittance of the devices, we were committed to fabricating fully transparent TFTs. In the selection of electrodes, we selected three transparent conductive oxides: AZO, GZO, and ITO. We separately explored their electrical performance in contact with the TFTs under different RF sputter power, find out the optimized RF power, and compare them.
a-ITZO TTFTs in contact with optimized ITO electrodes exhibited the highest electron mobility. In the linear region, the device exhibited Ion/Ioff of ~109, field-effect mobility (μFE) of 38.95 cm2/V-s, subthreshold swing (S.S.) of 123 mV/dec, and threshold voltage (Vth) of 2.52" V" . The higher mobility was attributed to the optimized ITO had the lowest resistivity. The devices in contact with optimized GZO and AZO electrodes respectively exhibited μFE of 9.29 cm2/V-s and 7.75 cm2/V-s, the Ion/Ioff were both ~108. The electrical properties of the devices were mainly limited by the resistivity of optimized GZO and AZO, which were still relatively large compared to the general transparent conductive oxides, thus affecting the on-current performance of the devices.
In the TFTs stability test, the negative bias illumination stress (NBIS) has been recognized as the significant index for metal oxide TFTs. In this experiment, a-ITZO TTFTs with optimized GZO, AZO, and ITO electrodes were stress under VGS of for a stress duration of 3000s. The negative Vth shift were -0.43 V, -0.43 V, and -0.57 V respectively. The devices in contact with GZO and AZO electrodes exhibited more stable against NBIS test than ITO electrode. We speculated that the narrower bandgap of ITO than GZO and AZO was more sensitive to illumination and caused more severe device degradation.
In this study, the a-ITZO TTFTs were successfully fabricated by USPD. The USPD method has considerable advantages in process time and cost. In the electrical performance, the devices we fabricated have the advantages of high transmittance, high electron mobility, and good stability. Therefore, a-ITZO TFTs become as an alternative for a-IGZO TFTs in the next-generation of the flat panel display industry which requires higher electron mobility and larger sized.

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