Let Rf = the feedback resistor value
Ri = the input resistor value
There are several things that you can check:
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Is the Op Amp internally compensated for unity gain? If not, check that the external compensation (if there are provisions for this) is adequate for the closed loop gain (Rf/Ri) that you are providing.
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Check that the connections to the OP Amp inputs are short.
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Check that you have adequate power supply bypassing capacitors, with short connections, at the Op Amp power terminals. The capacitors must have low ESR (equivalent series resistance) at the frequency of interest. Usually ceramic types work well.
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Regards,
Kral