射频磁控溅射ZrW_2O_8薄膜的高温退火研究

Effects of Post-Deposition Annealing on ZrW_2O_8 Thin Films by Radio Frequency Magnetron Sputtering

采用ZrW2O8陶瓷靶材,以射频磁控溅射法在不同基片上沉积制备ZrW2O8薄膜。利用X射线衍射(XRD)仪和扫描电子显微镜(SEM)研究靶材性能和退火温度、气氛以及基片对薄膜的相组成、表面形貌的影响。结果表明:ZrW2O8靶材具有较高的纯度和致密度,磁控溅射制备的薄膜为非晶态,在730℃左右通氧条件下退火后得到择优生长的ZrW2O8薄膜;在750℃左右退火得到三方相ZrW2O8薄膜;在1200℃密闭的条件下淬火得到立方相ZrW2O8薄膜;在15到700℃温度区间内,制备的立方相ZrW2O8薄膜负热膨胀系数为–14.47×10-6K-1,随着退火温度的提高,薄膜出现一些孔洞和裂纹。

The ZrW2O8 thin film of negative thermal expansion CNTE）, as a novel functional material, has various potential applications in optics, microelectronics and micro-machine. The ZrW208 thin films were deposited on different substrates by RF magnetron sputtering with pure ZrW2Os ceramic as target. The performance of target and the effects of post-deposition annealing temperature, atmosphere and substrate on the microstructure and morphology of the ZrW208 thin films were investigated by X-ray diffraction （XRD） and scanning electron microscopy （SEM）. The results indicate that the target is compact and composed of pure ZrW2Os. The as-deposited ZrW208 film shows an amorphous phase. The ZrW2Os film with preferred orientation can be prepared in oxygen atmosphere by annealing at 730 ℃, the trigonal ZrW2Os film can be prepared by annealing at 750 ℃, and the cubic ZrW208 film can be prepared in a sealed cell at 1200 ℃, and the negative thermal expansion coefficient of the resulting cubic ZrW208 film is -14.47×10-6 K-1 in the temperature range from 15 ℃ to 700 ℃. With the increase of armealing temperature, some holes and deficiencies appear in the surface of films.