Method of fabricating a programmable read-only memory cell incorporating an antifuse utilizing ion implantation

A method of fabricating a semiconductive programmable read only memory cell, comprising:

• (a) locally oxiding selected surface regions of a body of monocrystalline semiconductor of first type conductivity to produce a plurality of isolated semiconductor regions in said body;
• (b) introducing dopant impurities of opposite second type conductivity in a first one of said isolated semiconductor regions to produce a first region of second type conductivity forming a semiconductive junction with said body at a location beneath the surface of said body;
• (c) implanting ions of sufficiently high energy and density within a surface layer of said first region to convert said surface layer to amorphous form that is electrically and irreversibly switchable from high resistance state to low resistance state;
• and
• (d) introducing dopant impurities of first type conductivity in a second one of said isolated semiconductor regions lying adjacent to said first isolated region to form a low resistance contact region at the surface of said body.