Hello Yoonsun,
The figure that Umesh indicated gives a good picture of the relationship between dBc and dBFS. As you have noted, the AD9467 datasheet SFDR specification is in dBFS, and the amplitude of the test signal (carrier) is -1dBFS. SFDR = 92dBFS means that the span from Full-Scale to the worst spur is 92dB. Because the test signal (carrier) is 1dB below Full-Scale (-1dBFS), you would subtract 1dB from SFDR(dBFS) to get SFDR(dBc).
For Ain = -1dBFS, 92dBFS - 1dB = 91dBc.
If you are comparing several ADCs, you also need to consider what the Full-Scale input swing is. For the AD9467, the Full-Scale input swing is 2.5Vpp differential. For a direct comparison, you would need to compare to other ADCs with similar Full-Scale input swing.
Please take care.
Doug