We present the results of a comparative 1/f noise study on experimental MODFET’s of two fabrication processes. The two processes differ in the way the gate is etched. The first process uses etching fluids, the second plasma etching. The last process may lead to considerable damage in the semiconductor layer under the gate. We measured both the 1/f noise in the gate source voltage and in the drain source voltage. We compared the results of both processes with the results of commercial available transistors. We found that the 1/f noise in the gate source voltage is increased clearly by the damages caused by the plasma etching, whereas the 1/f noise in the drain source voltage shows no apparent difference between the two production processes.