Brake noise

I have a 2000 Rav4 & there is a squeeking noise coming from the rear brakes when I let off the brakes. The brakes work fine & make no noise when using the brakes. It makes the noise only when I release the break pedal even if the car has been sitting in the garage for a while & the noise is coming from the rear of the car. I was told the pads can be sprayed with something to stop this. Is that true or can someone tell me how to do this?

It is probably the brake cleaner. Since you mentioned pads in your rear drive, you probably have a disk and not drum. Here is what you can do.
1) Chock the front wheels
2) Disengage emergency brake
3) Remove wheels
4) Remove the pads.
5) Clean the rotor and pads with the brake cleaner. Read the instruction on the container.