In order to overcome the problems of traditional fabrication of semiconductor field effect transistors (FET), such as material damage, limited alignment accuracy, the difficulty of transferring the electrode and high cost, a fabrication technique of semiconductor FET based on a flexible stencil technology was proposed. Ultra-violet lithography technology can be used to fabricate the flexible stencil. Then, the stencil was directly scooped up, heated and dried. The metal was deposited by ion beam sputtering technique, and N-channel depletion FET was obtained by transferring semiconductor CdSe nanobelts to the electrode, which confirmed the functionality and the feasibility of this technique. The technique has low cost and low material damage, and it provides a new way to fabricate integrated semiconductor devices.