from the region surrounding the drain and source openings and finally the metal layers are heated until they alloy with each other and the gaas surface fig3 shows a top view of the structure illustrated in fig2 after ohmic contacts 115 and 116 are formed in regions 113 as illustrated in fig4 a photoresist layer 120 is deposited spun on ohmic contacts 115 and 116 and dielectric layer 110 by standard optical photolithographic techniques an area 125 of photoresist layer 120 corresponding to the base area of gate electrode is selectively removed the thickness of photoresist layer 120 is in the range of 1 to 1 5 microns a distance w across area 125 taken in the plane of fig4 is preferrably in the range of 0 65 to 1 micron the structure is then metallized a metal layer 130 typically made of aluminum having a thickness in the range of 1000 to 1500 angstroms is deposited by angle evaporation techniques on photoresist layer 120 sidewall 121 of photoresist layer 120 and dielectric layer 110 however thicknesses as low as 500 angstroms can be used during the aluminum metal deposition gaas wafer 100 is tilted at an angle in the range of 10 to 14 degrees off the plane normal to the incident aluminum beam indicated by arrows 122 the result of having the aluminum evaporation occur at an angle in the range of 10 to 14 degrees is that the photoresist layer sidewall 128 shadows an area 129 of.