  Whispering-gallery mode crystalline resonators currently maintain the best
quality factor (Q) record, however, compact on-chip packaging is still a
challenge although various coupling architectures have been developed. Here, a
chemical etching method is proposed to fabricate a miniaturized tapered fiber
waveguide on silicon substrate. The Marangoni effect is implemented to reduce
the surface roughness of the cone region. The optical loss of 0.1 dB/mm is
obtained, and the Q of on-chip crystalline resonator exceeds 108. Additionally,
TEC is implanted in the package to actively customize the temperature, and the
temperature response of 18 pm/K is consistent with the theoretical calculation.
