温度对飞秒激光沉积ZnO/Si薄膜的结构和性能的影响

Effect of Temperature on Structure and Properties of Femtosecond Laser Deposited Silicon Based Zinc Oxide Thin Films

通过飞秒脉冲激光（50Is，800nm，1kHz，2mJ）沉积技术在n型Si（100）单晶基片上制备了ZnO薄膜。详细研究了基片温度变化以及退火处理对ZnO薄膜的结构、表面形貌及光学性质的影响。X射线衍射（XRD）结果表明，不同温度下（20-350℃）生长的ZnO薄膜具有纤锌矿结构，并且呈c轴择优取向；当基片温度为80℃时，薄膜沿（002）晶面高度择优生长；当基片温度为500℃时薄膜沿（103）晶面择优生长，场发射扫描电子显微镜（FEEM）结果表明薄膜呈纳米晶结构，并观察到了ZnO的六方结构。进一步通过透射光谱的测量讨论了基片温度及退火处理对ZnO薄膜光学透射率的影响，结果表明退火后薄膜的透射率增大。

Zinc oxide films were prepared on n type Si（100） substrate using femtosecond laser deposition with laser parameters as follows： pulse width 50 fs, wavelength 800 nm, repeat frequency 1 kHz, and pulse energy 2 mJ. The effects of substrate temperature change and annealing on the structure, surface morphology and optical properties of the ZnO films were discussed. The X-ray diffraction （XRD） results showed the ZnO films deposited under different temperature （20-350 ℃） were with wurtzite structure and highly c-axis oriented. When the substrate silicon was 80 ℃ the film was highly （002）-oriented, and （103）-oriented at 500 ℃. The nano-crystal structure of the films and hexagonal structure of ZnO were observed with a field-emission electron microscope （FEEM）. The effects of substrate temperature and annealing on the optical transmissivity of ZnO films were discussed by transmitted spectra, and the transmissivity was increased after annealing.