在這一系列對氮化鎵材料的研究中，透過調變氮化鎵成核層上的條件，加以搭 配電性量測的結果，研究出利於氮化鎵的成長條件。從 XRD 的分析及室溫下 I-V 曲 線擬合串聯電阻的數值顯示出其成核層腔體條件不只以 Nakamura 提出的低溫環境，
加以高壓條件對於樣品的磊晶品質確實大有改善。但受限於未摻雜氮化鎵為高阻值 的材料特性，以致於電性量測時受到高阻抗因素而造成量測上的誤判。加以樣品 807、808、810 及 811 疑似有大量缺陷捕捉載子的行為而有較大漏電流的形成，從逆 偏 I-V 曲線中，與溫度無關的電流變化加以低溫擬合出遠大於 1 的 ideal factor 和 較小的 barrier height 皆顯示此樣品的電流傳導機制不是以 pure thermionic emission 為主，而是疑似有缺陷捕捉載子而形成的穿隧電流產生。在 C-F 量測中，
樣品 807 與 810 從反曲點擬合出的樣品阻值為 105 Ω，以致於在 DLTS 的量測頻率 F=1 MHz 其電容值受到 RC 效應而被拉至接近於零，因此在 DLTS 的量測中疑似缺陷訊號過 於微弱以致於此兩片樣品無法透過量測更深入針對缺陷能階做探討。反到是樣品 808 及 811 由於其阻值降低一個數量級，因此我們可以透過在 F=1 MHz 時的電性量測對 樣品做更進一步的探討。此兩片樣品在 DLTS 都量測到同一缺陷能階，但其缺陷訊號 受到樣品阻值影響以致於有峰值反向導致主峰值的溫度有所平移甚至峰值訊號過於 微弱等影響。因此，我們若想針對此缺陷能階做探討，首當其推我們必須先解決樣 品阻抗對量測的影響。
為了改善實驗所量測到高阻抗的氮化鎵材料，於是我們另外磊晶一片樣品 normal，其結構與樣品 807 相似，也就是整片磊晶層皆為低壓 200 mbar 的腔體條件，
其差異在於多磊晶一層 n 型氮化鎵材料於成核層和未摻雜氮化鎵的中間。實驗結果 顯示此 n 型材料的磊晶層將有助於降低樣品電阻達 3 個數量級且有減少漏電流的形 成。變溫 I-V 量測也顯示其電流傳導機制是以 pure thermionic emission 為主，故 此樣品的研究效應大於另外四片。
由於我們都知道氮化鎵因為其本質缺陷--氮錯位的存在，而使得藍光二極體的 發光效率降低。於是透過此片樣品 normal 的研究，我們藉由 DLTS 量測出此缺陷能 階位於導電帶下方 0.5 eV，捕獲截面積為 10-16 cm-3，並且此能階將不受到缺陷內電 子濃度影響而改變。
為了更進一步研究此缺陷的電性行為，我們透過 DLTS 量測載子跳回缺陷時所需 克服的能障。藉由調變 filling pulse width，可發現其能障會受到缺陷內載子濃度 的增加而變小，引用 Tadeusz Wosinski[1]所提出的缺陷理論分析，進而求得缺陷內 無電子為 empty state 時的能障高度為 0.37 eV，參考文獻指出此缺陷疑似為氮原子 取代鎵空穴而成 (NGa ↔VGa+Ni)。於是我們大膽假設此缺陷會產成一個類似 Schottky 的 intrinsic barrier height 為 0.52 eV (
φ
B0 =Vbi+φ
n =0.37+0.15)，於是，我們認定此缺陷同時具有 emission 等於 capture 的相同能障。
引述 InAs QDs 的模型，此結構透過 Nitrogen 的摻雜，會使得其 band 受到 QDs 內電子濃度影響而產生一個 intrinsic barrier height，套用此模型觀念於我們所 量測到的缺陷能階，認定此缺陷由於只有一個穩態能階為 0.5 eV，又其會產生一個 barrier 且其能障會受到缺陷內電子濃度影響，進而計算出其 intrinsic barrier height 為 0.52 eV，表現出 dot-like defect 的電性特質。
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