Question 16.19: Explain the term antifuse....
Explain the term antifuse.
An antifuse is a programmable element invented by Actel Corporation and is named as programmable low impedance circuit element (PLICE). It is normally an open device in which electrical connection is established by the application of a programmable voltage. The antifuse is a vertical, two-terminal structure. It consists of a polysilicon layer on top. N+ doped silicon on the bottom, and an oxide-nitrite-oxide dielectric layer inbetween. The size of an antifuse is about 1.8 \mu \mathrm{m}^{2}. It has a low resistance, typically 500 \Omega when programmed and over 100 \mathrm{M} \Omega when in the unprogrammed state. The antifuse is a very attractive alternative to EPROM, EEPROM, or RAM for use as a programmable element in a large programmable gate array. It is a one time programmable device.