Abstract: The present invention relates to an integrated circuit which includes complementary MOS transistors (e.g., a CMOS circuit), an EEPROM, and to a method of making the integrated circuit. The EEPROM is incorporated in the circuit in such a manner that it does not adversely affect the high performance, low voltage operation of the CMOS circuit. Also, the EEPROM is designed so that it is programmable at a low voltage which is compatible with the low voltages typically used with the CMOS circuit. The EEPROM includes a floating gate and a control gate which have a large area of overlap so as to provide a high capacitance therebetween. This provides a high ratio (e.g., about two or greater) of the floating gate to control gate capacitance divided by the floating gate to substrate capacitance to provide the EEPROM with the low voltage operation. To make the integrated circuit, standard CMOS process steps using design rules of about two microns or less are used to make the MOS transistors.

Abstract: A p-channel depletion device in a MOSFET is formed and preferably comprises a silicon substrate, an N-well region, P+ source and drain regions, and a polysilicon gate which has been appropriately doped to be of a P- conductivity type. The resulting structure performs analogously to a depletion device formed in accordance with conventional methods wherein a depletion mask and implant are utilized and are characterized by a threshold voltage of approximately +250 millivolts or greater.

Abstract: The present invention relates to an integrated circuit which includes complementary MOS transistors (e.g., a CMOS circuit), an EEPROM, and to a method of making the integrated circuit. The EEPROM is incorporated in the circuit in such a manner that it does not adversely affect the high performance, low voltage operation of the CMOS circuit. Also, the EEPROM is designed so that it is programmable at a low voltage which is compatible with the low voltages typically used with the CMOS circuit. The EEPROM includes a floating gate and a control gate which have a large area of overlap so as to provide a high capacitance therebetween. This provides a high ratio (e.g., about two or greater) of the floating gate to control gate capacitance divided by the floating gate to substrate capacitance to provide the EEPROM with the low voltage operation. To make the integrated circuit, standard CMOS process steps using design rules of about two microns or less are used to make the MOS transistors.