convert voltage to current

In my project, I need a 20 microampere AC current sinewave signal, which is in 10kHz, it is too low, so I want to use the signal generator to generate a 5V voltage sinewave signal, then convert this voltage signal to current signal,
can I just use a 250k ohm resister to connect the singal generator and then get the current signal? if it doesn't work, how can i do it ?

All you need is a series resistor, you should be fine.