Martin Fabrice, Jan Marc-Etienne, Rey-Mermet Samuel, Belgacem Brahim, Su Dong, Cantoni Marco, Muralt Paul
Ceramics Laboratory, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland.
IEEE Trans Ultrason Ferroelectr Freq Control. 2006 Jul;53(7):1339-43. doi: 10.1109/tuffc.2006.1665082.
Polycrystalline A1N thin films were deposited by RF reactive magnetron sputtering on Pt(111)/Ti electrode films. The substrates were tilted by an angle ranging from 40 degrees to 70 degrees with respect to the target normal. A low deposition temperature and a high sputter gas pressure were found ideal for tilted growth. The resulting grain tilt angle amounts to about half the substrate tilt angle. For coupling evaluation, 5 GHz solidly mounted resonator structures have been realized. The tilted grain A1N films exhibited a permittivity in the 9.5-10.5 range and loss tangent of 0.3%. Two shear modes as well as the longitudinal mode could be clearly identified. The coupling coefficient k2(eff) of the fundamental thickness shear mode (TS0) was found to be about 0.5%, which is compatible with a c-axis tilt of about 6 degrees.
通过射频反应磁控溅射在Pt(111)/Ti电极薄膜上沉积多晶AlN薄膜。衬底相对于靶法线倾斜40度至70度。发现低沉积温度和高溅射气体压力有利于倾斜生长。所得晶粒倾斜角约为衬底倾斜角的一半。为了进行耦合评估，实现了5GHz固态安装谐振器结构。倾斜晶粒的AlN薄膜的介电常数在9.5-10.5范围内，损耗角正切为0.3%。可以清楚地识别出两种剪切模式以及纵向模式。发现基模厚度剪切模式（TS0）的耦合系数k2(eff)约为0.5%，这与约6度的c轴倾斜度相符。
