Effect of temperature on SAW devices

Hi,

I'm trying to simulate the effect of temperature on Surface Acoustic Waves (SAW) devices . I'm using the module "Piezoelectric devices" and so I get the response of the admittance in a certain range of frequency. The problem is that when I modify the substrate temperature there is no change in the response of the admittance. Can someone help me with this? It should include more modules in the simulation? Thanks