A system and method are disclosed for providing drain avalanche hot carrier (DAHC) programming for non-volatile memory (NVM) applications. A memory cell of the present invention comprises a program transistor and a control capacitor, each having a gate coupled together to form a floating gate. The size of the program transistor is selected to create a coupling ratio between the program transistor and the control capacitor that is large enough to facilitate a Fowler-Nordheim erase process and small enough to facilitate DACH programming. A source bias voltage is supplied to the source of the program transistor to increase the hot electron injection rate and to decrease the hot electron generation rate in the memory cell.
A system and method are disclosed for providing EEPROM devices that combine the high endurance features of complex and expensive EEPROM devices and the low manufacturing costs of CMOS compatible EEPROM devices. A memory cell of the invention comprises a control capacitor, an erase capacitor, and a program capacitor, each of which comprises an NMOS transistor. The gates of the three NMOS transistors are connected together to form a floating gate. The drain of the NMOS transistor of the program capacitor is separately connected so that the program capacitor can also serve as a read transistor. A memory cell of the invention can be programmed or erased in an array of memory cells without disturbing the other memory cells in the array.
A system and method are disclosed for enhancing the performance of erase operations in CMOS compatible EEPROM memory cells. An EEPROM memory cell is described in which the erase voltage and the coupling ratio of the EEPROM memory cell are simultaneously decreased while maintaining the erase performance (e.g., erase speed) of the EEPROM memory cell. Significant improvement in the endurance of CMOS compatible EEPROM devices is obtained due to the enhanced erase performance of the EEPROM memory cells of the present invention.
A system and method is disclosed for providing a CMOS compatible single poly electrically erasable programmable read only memory (EEPROM) with memory cells that comprise an NMOS program transistor. In a first embodiment the memory cells of the EEPROM comprise a PMOS control capacitor. In a second embodiment the memory cells of the EEPROM comprise an NMOS control capacitor. A well bias voltage is applied to the NMOS program transistor instead of a gate bias voltage. The well bias voltage enables the injection of (1) channel hot electrons, (2) second hot electrons initiated by the channel hot electrons, and (3) drain impact ionization hot electrons into a floating gate of the NMOS program transistor.