本研究的目標為製備鉍銅硒氧(BiCuSeO)薄膜，並期望鉍銅硒氧薄膜能以磊晶的方式成長至(001)鈦酸鍶單晶基板上。我們嘗試以溶膠凝膠法、脈衝雷射沉積法、射頻磁控濺鍍法，三種不同薄膜製備方式合成、沉積鉍銅硒氧薄膜；而脈衝雷射沉積及射頻磁控濺鍍所用的靶材之製備方式也將於內文中詳盡討論。
在溶膠凝膠法製程中，我們嘗試不同條件最後成功配置含Bi、Cu、Se元素之 sol-gel溶液，隨後在不同氣氛下對塗佈在矽基板上的sol-gel薄膜進行熱處理。然而在熱處理過程中發現薄膜中的Bi、Se元素相當容易揮發，特別是Se元素，會於溶膠溶液逐漸蒸乾的過程中先行揮發，導致成分嚴重偏離化學計量比，無法形成BiCuSeO相。
以脈衝雷射沉積法沉積BiCuSeO薄膜，實驗結果顯示雷射能量密度需大於0.65 J/cm2以上才可將各元素依靶材比例沉積於基板上，而基板溫度為400˚C時較適合BiCuSeO薄膜成長。如若要薄膜形成BiCuSeO相，雷射能量密度需再提高至0.90~1.80 J/cm2，且薄膜亦會隨雷射能量密度提高而變得緻密。於SrTiO3基板上成長之BiCuSeO薄膜，雷射能量密度需達到1.50 J/cm2才可形成(001)之擇優取向，但薄膜中含有其他雜相。此外，經霍爾效應量測得知BiCuSeO薄膜電導率約介於102~103 S×m-1之間。
利用射頻磁控濺鍍法沉積BiCuSeO薄膜，最初以製程壓力50 mtorr、功率60~80W沉積薄膜，但發現鍍率過快(23.3~31.6 nm/min)不利於磊晶成長。將功率降低至30W(即減少鍍率)，基板溫度設置在300~500˚C之間沉積BiCuSeO薄膜，但所得薄膜之成分嚴重偏離化學計量比。進而降低製程壓力至10 mTorr，而功率則稍增至40W，發現於基板溫度100~350˚C範圍皆可形成BiCuSeO相。濺鍍於SrTiO3基板之薄膜其結構會隨基板溫度變化，常溫時為非晶結構，100˚C時開始出現BiCuSeO相且有(110)擇優取向，150˚C時BiCuSeO薄膜擇優取向更趨明顯，而200˚C~300˚C時擇優取向則變差，350˚C時BiCuSeO薄膜完全退化為多晶隨機取向。由霍爾效應量測可知薄膜皆為P-type，電導率約為10~103 S×m-1，其中以150˚C沉積於SrTiO3基板之薄膜電導率最高，可能因其有最佳(110)擇優取向所致。對(110)擇優取向薄膜進行精密X射線繞射分析，發現薄膜在基板平面有兩組不同晶粒取向，即薄膜晶粒之[001]方向大約分別平行於基板之[110]和[1 ̅10]方向，兩組晶粒取向之間夾角為90˚。

In this study, the growth of BiCuSeO (BCSO) films on Si and (001) SrTiO3 substrates was attempted by a number of techniques, including sol-gel, pulse laser deposition (PLD) and RF magnetron sputtering. The growth with sol-gel technique was unsuccessful due to the preferential losses of Bi and Se during the sintering process of the coated gel films. In the PLD growth, the films of BCSO phase were obtained when the substrate temperature was set at 400 C and the laser fluence between 0.90~1.80 J/cm2. The porosity of the deposited films was found to decrease as the laser fluence increased. For the BCSO films grown on SrTiO3, a preferred (001) texture was developed when the fluence was increased to 1.50 J/cm2, although the films also contained some secondary phases. The conductivity of the PLD grown BCSO films was measured to be 102~103 Sm-1. The sputtering growth was carried out in Ar atmosphere. The BCSO films could be grown with the following sputtering parameters: Ar pressure 10 mTorr, sputter power 40W, and substrate temperature 100~350C. The microstructures and textures of the films grown on SrTiO3 varied significantly with the substrate temperature. The films grown at room temperature was amorphous, while those grown at 100C showed the desired BCSO phase with a preferred (110) orientation. The increase of substrate temperature to 150˚C led to a better (110) texture. However, further increase of the substrate temperature to 200~300C resulted in the degradation of the (110) texture and the texture disappeared at 350C. High-resolution X-ray analysis indicated that the (110) textured films consisted of two in planed orientations with the films [001] axis roughly parallels to the substrates [110] and [1 ̅10] axes, respectively, i.e. the two in-plane orientations had a relative angle of 90. All the BCSO films grown by sputtering were confirmed to be P-type by the Hall-effect measurement with the conductivity being 101~103 Sm-1. The films grown on SrTiO3 at 150 C showed the highest conductivity, presumably due to their high degree of (110) texture.

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