Thin‐film tunnel junctions using a semiconductor rather than an oxide barrier have been fabricated. Niobium, used for the bottom layer, and the semiconducting center layer were deposited using rf sputtering techniques, while the top layer was evaporated lead. Sputtering was done from high‐purity single‐crystal slices of Ge, Si, and GaAs and from polycrystalline InSb. Superconductive tunneling was observed in most samples. The semiconductor tunnel junctions were somewhat light/heat sensitive and also exhibited a nonlinearI‐Vcharacteristic at voltages greater than the superconducting energy gap to a greater extent than comparable oxide devices. Excess current was noted in the devices at voltages below the superconducting gap and the measured gap of the niobium film was found to be reduced from that of pure material. Although initial devices were inferior to good oxide junctions, present results show that techniques of rf‐bias sputtering and sputter etching have strong possibilities for the production of deposited insulator junctions.