(福州大學(xué) 材料科學(xué)與工程學(xué)院，福州 350116)
摘 要: 采用射頻磁控濺射Mg-Si二元復(fù)合靶制備Mg2Si熱電薄膜，研究濺射功率、真空退火溫度及退火時間對其性能的影響，探究較優(yōu)的Mg2Si薄膜制備工藝。利用掃描電子顯微鏡(SEM)、X射線衍射儀(XRD)、霍爾效應(yīng)測試儀、薄膜Seebeck系數(shù)測量系統(tǒng)對薄膜特性進行測試。由薄膜斷面的能譜分析可知，Mg、Si元素在薄膜中分布均勻，且薄膜中Mg與Si摩爾比為2:1，與Mg2Si相的組成摩爾比相符；XRD測試結(jié)果表明，濺射功率、真空退火溫度及退火時間對薄膜的成膜質(zhì)量均有影響。霍爾效應(yīng)測試及Seebeck系數(shù)測量結(jié)果表明:所制備的Mg2Si薄膜均為n型半導(dǎo)體薄膜，其Seebeck系數(shù)的取值范圍為-278.648~-483.562 μV/K，薄膜電導(dǎo)率的取值范圍為1.240~46.926 S/cm；120 W濺射功率下沉積的Mg2Si薄膜經(jīng)400 ℃真空退火保溫3 h后，獲得最大功率因子，其值為0.364 mW/(m？K2)。
關(guān)鍵字: Mg2Si薄膜；射頻磁控濺射；工藝優(yōu)化；熱電性能
（School of Materials Science and Engineering, Fuzhou University, Fuzhou 350116, China）
Abstract:The Mg2Si thermoelectric thin films were fabricated by radio frequency magnetron sputtering with the Mg-Si binary composite target. The effects of sputtering power, vacuum annealing temperature and annealing time on the qualities of Mg2Si thin films were studied to find out the optimal preparation process. The properties of the thin films were tested by scanning electron microscope (SEM), X-ray diffraction (XRD), Hall effect tester, film Seebeck coefficient measurement system. As showed in energy dispersive X-ray spectrum of the Mg2Si thin film profile, Mg and Si in the thin films distribute uniformly and the mole ratio of Mg to Si in thin films is about 2:1, which is consistent with the mole ratio of Mg2Si phase. XRD results show that the sputtering power, vacuum annealing temperature and annealing time have effects on the film quality. The test results of Hall measurement and Seebeck coefficients measurement reveal that all the samples are n-type. The Seebeck coefficients are in the range of -278.648- -483.562 μV/K, and the electrical conductivities are in the range of 1.240-46.926 S/cm. Among all, the Mg2Si thin film deposited with 120 W and annealed at 400 ℃ for 3 h have the highest power factor of 0.364 mW/(m？K2).
Key words: Mg2Si thin film; radio frequency magnetron sputtering; optimal preparation process; thermoelectric properties
