1. An antifuse having upper and lower electrodes and amorphous silicon material disposed between generally parallel opposing portions of the upper electrode and the lower electrode, the amorphous silicon material comprising in an unprogrammed state the type of silicon material that results from a plasma enhanced chemical vapor deposition of silicon without subsequent exposure to temperatures in excess of 500 degrees Centigrade, and the opposing portions of the upper and lower electrodes contacting said amorphous silicon material being of a low silicon-diffusible material and being spaced apart a particular distance and having a particular area for limiting, in conjunction with the amorphous silicon material, current through the amorphous silicon to about 10 nanoamperes or less at 5.5 volts in the unprogrammed state, wherein the opposing portions of the upper and lower electrodes are spaced apart the particular distance for attaining a resistance through the amorphous silicon material in a programmed state under 200 ohms.