本論文研究使用有機高分子介電層之N型有機薄膜電晶體(organic thin-film transistors, OTFTs)。以自行調配的交聯聚4-乙基苯酚(C-PVP)，PVP與PMF為8:4 wt%的C-PVP取代二氧化矽當作有機薄膜電晶體的絕緣層，同時用不同PVP與PMF重量百分濃度比的C-PVP作為修飾層。並使用自行合成的十八烷基駢苯衍生物(N,N'-dioctadecyl-3,4,9,10- perylene tetracarboxylic diimide, PTCDI-C18H37)作為半導體主動層材料製作有機薄膜電晶體元件，量測其電特性與薄膜特性比較之間差異。
本實驗分為兩個部份，第一部分研究以不同PVP與PMF重量百分比濃度C-PVP修飾層對元件電特性之影響。由於PTCDI-C18H37直接成長在PVP與PMF為8:4 wt%的C-PVP絕緣層上所製作的元件，次臨界擺幅(S.S.)與OFF電流(IOFF)過大。可能是因為C-PVP絕緣層與PTCDI-C18H37薄膜的表面能的非極性項不匹配所造成，所以我們在絕緣層旋轉塗佈上不同PVP與PMF重量百分濃度比例的C-PVP當作修飾層，改善PTCDI-C18H37成膜環境。從XRD分析可發現PTCDI-C18H37薄膜成長在以PVP與PMF為4:2 wt% C-PVP修飾層所製作的元件有最大的結晶尺寸。所測量出的元件電特性也較其他PVP與PMF重量百分濃度比例C-PVP作為修飾層所製成的元件佳。由AFM分析結果推測PTCDI-C18H37薄膜的結晶品質可能是受到C-PVP修飾層表面孔洞數量及面積所影響。接著將修飾層硬烤時間加倍，發現C-PVP修飾層表面孔洞缺陷隨硬烤時間增加變大，使PTCDI-C18H37薄膜結晶性下降而影響載子傳輸。其中以PTCDI-C18H37薄膜成長在以PVP與PMF為2:4 wt%的C-PVP修飾層所製作的元件電特性與薄膜特性變化最小，所以推論PVP與PMF為2:4 wt%的C-PVP修飾層有較佳的溫度耐性。
本論文第二部份研究將PTCDI-C18H37薄膜成長在不同溫度的PVP與PMF為2:4 wt%之C-PVP修飾層所製作成的元件，比較PTCDI-C18H37薄膜成膜時基板溫度對電特性與薄膜特性的影響。由XRD分析可以發現當基板溫度提高晶格尺寸也增加，表示PTCDI-C18H37薄膜結晶性變好。從拉曼相減光譜也可以看出隨著成膜時基板溫度提高，PTCDI-C18H37薄膜結晶性提高而導致分子振動因自由度下降而減小。但從AFM圖可以看出當基板溫度增加時，C-PVP修飾層表面缺陷變多，所以造成基板溫度為100°C條件下的PTCDI-C18H37薄膜成長受到表面缺陷影響最多，因此所量量測到的PTCDI-C18H37薄膜晶格尺寸最小，以此條件製作的元件量測出的電特性也最差。因此我們發現C-PVP高分子膜對溫度極為敏感，長時間的加溫過程導致C-PVP修飾層表面劣化。由於頂部接觸式(top contact, TC)薄膜電晶體其通通在修飾層表面附近，推測元件電特性表現受到修飾層表面缺陷的影響大於基板加溫效應所提升的結晶性，所以整體元件電特性表現變差。

A polymer, cross-linked poly(4-vinylphenol) (C-PVP), is used as the dielectric layer of organic thin-film transistors (OTFTs) whose organic semiconductor, N,N'-dioctadecyl-3,4,9,10-perylene tetracarboxylic diimide (PTCDI-C18H37), was synthesized. The effects of the concentrations of C-PVP modification dielectric layers on the thin-film properties of PTCDI-C18H37 are studied. An OTFT with a low leakage current is obtained using a C-PVP polymer film with a weight concentration ratio of PVP to PMF of 8:4 as an insulating layer. C-PVP films with weight concentration ratios of PVP to PMF of 2:1, 2:4, 4:2, and 8:4, respectively, are used as the modification layer between the C-PVP (8:4) gate dielectric and PTCDI-C18H37 thin film. X-ray diffraction and Raman spectroscopy analyses show that the degree of molecular freedom and the crystalline size of PTCDI-C18H37 thin films deposited on a C-PVP surface with a concentration ratio of PVP to PMF of 8:4 are smaller than those of films grown at PVP to PMF weight concentrations of 2:1, 2:4, and 4:2. An excellent PTCDI-C18H37-based OTFT is obtained by modifying a device with a C-PVP film whose weight concentration ratio of PVP to PMF is 4:2. The baking time of the C-PVP modification layers is varied to study the thermal effects in the polymers. Long baking time for C-PVP modification layers causes surface defects, reducing the performance of PTCDI-C18H37-based OTFTs.
The PTCDI-C18H37 film is deposited on a SiO2 substrate modified by C-PVP with a weight concentration ratio of PVP to PMF of 2:4 at room temperature, 50, 75, and 100 °C. From the XRD analyses, the crystalline size of the PTCDI-C18H37 film deposited at 75 °C was the largest. A higher deposition temperature causes more holes on the surface of C-PVP modification layers, which indicates that an increase of electron traps results in a decrease of electron mobility.

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