A Novel 14 V Programmable 4 kbit MOS PROM Using a Poly-Si Resistor Applicable to On-Chip Programmable Devices

A novel fusible-link-type 4 kbit MOS programmable read only memory (PROM) has been developed with n-channel silicon-gate technology. The programmable element is a poly-Si resistor which makes an irreversible resistivity transition. A low programming voltage of 10 V and a small programming current of 4 mA is obtained by optimizing the undoped poly crystalline silicon (poly-Si) deposition conditions and reducing the electrode area of a poly-Si resistor. The fabrication is compatible with conventional silicon-gate processing. New clock generator and clamping circuits result in low-voltage and high-speed programming. High-speed reading is achieved by adopting a dual X-line layout. The fabricated 4 kbit PROM can be programmed within 5 μS by applying a voltage of less than 14 V. Measured access time is less than 130 ns and active power dissipation is 125 mW at 300 ns cycle time with a single 5 V supply.