resonant coil with high phase stability

Hi, all, my current project requires a high phase stability (<1 mill
degree @ 10 MHz / oC) resonant surface coil. I am trying to use a LC
resonant circuit to drive this surface coil, but its phase stability
is really poor (about 40-80 mill degree @ 10 MHz / oC ). I guess the
main problem comes from the used capacitor whose value is easily
changed by temperature. so my question is that can the crystal
oscillator help me more? or is there any other method to achieve this
requirement?

Thanks a lot.
.