用不同材料修飾改變基板表面特性，由X 光晶格繞射來判定五環素在排列上 並無相變化的產生，但在電性上則有明顯的變化。以電流電壓曲線和電容電壓曲 線互相比較，發現電晶體開啟順序和電荷開始累積的順序是ㄧ樣的，但是數值上 的差異是很明顯的，為了更了解這差異的來源，可使用儀器和引入模型來幫助分 析。
先利用電容的特性曲線計算被捕陷電量。為了分析捕捉陷阱的來源，我們分 為晶粒內部和晶粒邊界(grain boundary)兩部份來探討。晶粒內部可利用X光晶格 繞射的強度來觀察排列的情況，發現強度越強排列越整齊的，捕捉的載子是最少 的。而晶粒邊界必須分成兩個部份討論，X-Y平面與Z軸方向。X-Y平面則是先使 用原子力顯微鏡掃描五環素的表面形貌，之後利用MATLAB程式分析邊界長度，
五環素的厚度有100 Å與 600 Å，由程式分析的結果發現不同厚度可得到相同的 趨勢，邊界長度越長的元件，會越慢開啟；而Z軸方向晶粒有 300 Å，所以Z方向 的晶粒邊界陷阱捕捉是可以忽略的。緊接著利用接觸角量測經修飾之後的表面 能，推測五環素成長的模型。五環素的表面能比PVP和SiNx小，所以會形成層狀 結構，晶粒較大，邊界長度較短；而PMMA和HMDS修飾後表面的表面能比五環 素小，形成島狀結構，晶粒較小，邊界長度較長。邊界長度越長的元件，會使得 載子在傳輸時容易被陷阱捕捉，元件會較慢開啟；反之，邊界長度短的元件，載 子傳輸時不易被捕捉，元件開啟的時間就會較早。
元件經過不同材料修飾後改變整體捕捉陷阱密度，主要是因為五環素排列整 齊度與晶粒邊界多寡，造成元件特性的差異。元件開啟電壓主要是晶粒邊界多寡 決定，由此可知如果想要做出可調變的元件，可以利用不同材料的修飾層來調變 Vto。
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