- 學位論文
獨立式氮化鋁單晶基板特性研究
Characteristic of freestanding Aluminum Nitride Single Crystal Substrate
摘要
本論文使用反應性射頻磁控濺鍍法，在藍寶石和矽基板表面，所成長的鹽(NaCl)薄膜緩衝層上，設定反應性氣體為純氮及濺鍍工作氣壓為1.5x10-3 torr的製程條件，沉積氮化鋁(AlN)薄膜，分析氮化鋁的結晶性及光學性質，並將樣品浸泡於水，溶解鹽(NaCl)緩衝層，嘗試得到獨立的氮化鋁(AlN)薄片。 氮化鋁薄膜經由X光繞射，分析樣品的結晶面向及結晶品質，在反應性濺鍍氣體: 氬氣(Ar)與氮氣(N2)流量比為0(sccm) : 2(sccm)時，藍寶石基板及矽基板上的AlN薄膜皆為多晶結構，當氬氣(Ar)與氮氣(N2)流量比調為0(sccm) : 3(sccm)時，多晶的情況有明顯變化，當基板溫度為500O C時，具鹽(NaCl)緩衝層藍寶石基板上的氮化鋁(AlN)薄膜，其晶向結構為(002)優選取向。 因薄膜與基板間有氯化鈉緩衝層，所形成的多晶面向AlN薄膜樣品，其拉曼散射量測結果，在624 cm-1 與656 cm-1皆有氮化鋁的拉曼散射訊號。光學性質方面，在氬氣(Ar)與氮氣(N2)流量比為0:2的製程條件下，AlN薄膜在光波長633nm處的折射率為2.020，流量比為0:3時，該處的折射率升至2.037，AlN薄膜在光波長633nm處的消光係數在純氮的製程條件下約為 1.2x 10-3
並列摘要
In this thesis, we deposited AlN thin films on the substrates of NaCl/Sapphire wafer and NaCl/Silicon wafer by reactive RF magnetron sputtering system with 100% N2 reactive gas in working pressure 1.5x10-3 torr. Then to analyze crystallinity and optical property of AlN thin films. After that to soak the sample in water to dissolve the salt (NaCl) buffer layer to obtain freestanding AlN flake. The crystal orientation and crystal quality of AlN films is analyzed by X-ray diffractometer(XRD). The AlN films on the substrates of NaCl/Sapphire and NaCl/Silicon are all polycrystalline, as the flow ratio of reactive sputtering gas: argon (Ar) to nitrogen (N2) is 0 (sccm): 2 (sccm). The polycrystalline situation of AlN films changes significantly, as the flow ratio of reactive sputtering gas: argon (Ar) to nitrogen (N2) is adjusted to 0 (sccm): 3 (sccm) and the substrate temperature is 500O C, the crystal structure of the AlN film on the NaCl/Sapphire substrate becomes (002) preferred orientation. Due to the buffer layer of NaCl between the film and the substrate, as the substrate temperature is 400O C, the polycrystalline-oriented AlN film is formed, and its Raman scattering measurement results are 624 cm-1 and 656 cm-1 of AlN raman scattering signals. For optical properties, the refractive index of AlN film at the 633nm wavelength is 2.020 as the flow ratio of argon (Ar) to nitrogen (N2) is 0:2, and the refractive index of AlN film at the 633nm wavelength rises to 2.037 as the flow ratio of argon (Ar) to nitrogen (N2) is 0:3, and the extinction coefficient of AlN film at the 633nm wavelength is about 1.2 x 10-3 under all pure nitrogen processes.