Preparation And Research Of ScAlN Film Based On Substrate Of Ni Matrix Alloy

With the increasing miniaturization of micro systems, it is valuable to exploit vibration energy by means of vibrating cantilever beam. To obtain greater vibration and lighter weight, piezoelectric films deposited on flexible substrate have been investigated, which opens a new area of research for a wide range of applications. Few investigators have reported flexible substrate of polyimide. However, these polymer-type flexible substrates suffer from disadvantages such as they could not withstand higher temperatures, and a bottom metallic electrode layer has to be deposited to form a metal insulator metal(M-I-M) type structure for the device. So, a flexible substrate that is heat-proof and conductive is a good alternative for the investigation of flexible piezoelectric devices. Hastelloy alloys(C276) are a good choice as the flexible substrate. Among various piezoelectric materials. Al N films with c-axis orientation has been investigated widely for its various advantages, such as high hardness(>20 GPa), wide energy band gap(6.2 e V), and high thermal conductivity(3.9 W/cm K at RT). Recently, Sc Al N films got more and more attention, for great enhancement of piezoelectric response and electromechanical coupling coefficient.In this paper, Sc Al N films has been prepared on substrate of alloy by reactive magnetron sputtering, and master relevant technology, and the effect of sputtering parameters on the quality of Sc Al N film. And then, a comparetion of Sc Al N film deposited on Ni matrix alloy and Si was processed.The main research contents of the project include:1. Combining the test equipment of XRD, AFM, SEM, Precision LC unit, we optimized the sputtering parameters and got the best optimal parameters by DC reactive magnetron sputtering. It is demonstrated that the sputtering atmosphere, substrate temperature and sputtering power have key effect on the Sc Al N films deposition. And Sc Al N film with excellent properties has been prepared, which have FWHM of 1.9°, RMS of 2.624 nm, piezoelectric response of 7.3 p C/N.2. Based on the best optimal parameters, we prepared Sc Al N fims with c-axis and a-axis orientation on Ni matrix alloy, and compared the similarities and differences, and then made a theory exploration. We found that Sc Al N films with excellent properties could been prepared base on substrate of Ni alloy. However, higher power should been provided for higher surface energy and lattice mismatch. And Volmer-Weber has been demonstrated by RF sputtering.