A two-transistor memory cell based upon a thyristor for an SRAM integrated circuit is described together with methods of operation. The memory cell can be implemented in different combinations of MOS and bipolar select transistors, or without select transistors, with thyristors in a semiconductor substrate with shallow trench isolation. Standard CMOS process technology can be used to manufacture the SRAM.

A memory cell based upon thyristors for an SRAM integrated circuit can be implemented in different combinations of MOS and bipolar select transistors, or without select transistors, with thyristors in a semiconductor substrate with shallow trench isolation. Standard CMOS process technology can be used to manufacture the SRAM cells. Special circuitry provides lowered power consumption during standby.

A method of forming a complementary lateral bipolar SRAM device. The device includes: a first set and second set of lateral bipolar transistors forming a respective first inverter device and second inverter device, the first and second inverter devices being cross-coupled for storing a logic state. In each said first and second set, a first bipolar transistor is an PNP type bipolar transistor, and a second bipolar transistor is an NPN type bipolar transistor, each said NPN type bipolar transistor having a base terminal, a first emitter terminal, a second emitter terminal, and a collector terminal. Emitter terminals of the PNP type transistors of each first and second inverter devices are electrically coupled together and receive a first applied wordline voltage. The first emitter terminals of each said NPN transistors of said first inverter and second inverter devices are electrically coupled together and receive a second applied voltage. The second emitter terminal of one NPN bipolar transistor of said first inverter is electrically coupled to a first bit line conductor, and the second emitter terminal of the NPN bipolar transistor of said second inverter device is electrically coupled to a second bit line.

A method of forming a complementary lateral bipolar SRAM device. The device includes: a first set and second set of lateral bipolar transistors forming a respective first inverter device and second inverter device, the first and second inverter devices being cross-coupled for storing a logic state. In each said first and second set, a first bipolar transistor is an PNP type bipolar transistor, and a second bipolar transistor is an NPN type bipolar transistor, each said NPN type bipolar transistor having a base terminal, a first emitter terminal, a second emitter terminal, and a collector terminal. Emitter terminals of the PNP type transistors of each first and second inverter devices are electrically coupled together and receive a first applied wordline voltage. The first emitter terminals of each said NPN transistors of said first inverter and second inverter devices are electrically coupled together and receive a second applied voltage. The second emitter terminal of one NPN bipolar transistor of said first inverter is electrically coupled to a first bit line conductor, and the second emitter terminal of the NPN bipolar transistor of said second inverter device is electrically coupled to a second bit line.

A semiconductor device includes: a first cell; a second cell; a first match line and a second match line; a first search line pair, first data being transmitted through the first search line pair; a second search line pair, second data being transmitted through the second search line pair; a first logical operation cell connected to the first search line pair and the first match line, and configured to drive the first match line based on a result of comparison between information held by the first and second cells and the first data; and a second logical operation cell connected to the second search line pair and the second match line, and configured to drive the second match line based on a result of comparison between information held by the first and second cells and the second data.

A semiconductor device includes: a first cell; a second cell; a first match line and a second match line; a first search line pair, first data being transmitted through the first search line pair; a second search line pair, second data being transmitted through the second search line pair; a first logical operation cell connected to the first search line pair and the first match line, and configured to drive the first match line based on a result of comparison between information held by the first and second cells and the first data; and a second logical operation cell connected to the second search line pair and the second match line, and configured to drive the second match line based on a result of comparison between information held by the first and second cells and the second data.

A two-transistor memory cell based upon a thyristor for an SRAM integrated circuit is described together with a process for fabricating it. The memory cell can be implemented in different combinations of MOS and bipolar select transistors, or without select transistors, with thyristors in a semiconductor substrate with shallow trench isolation. Standard CMOS process technology can be used to manufacture the SRAM.

A method of forming a complementary lateral bipolar SRAM device. The device includes: a first set and second set of lateral bipolar transistors forming a respective first inverter device and second inverter device, the first and second inverter devices being cross-coupled for storing a logic state. In each said first and second set, a first bipolar transistor is an PNP type bipolar transistor, and a second bipolar transistor is an NPN type bipolar transistor, each said NPN type bipolar transistor having a base terminal, a first emitter terminal, a second emitter terminal, and a collector terminal. Emitter terminals of the PNP type transistors of each first and second inverter devices are electrically coupled together and receive a first applied wordline voltage. The first emitter terminals of each said NPN transistors of said first inverter and second inverter devices are electrically coupled together and receive a second applied voltage. The second emitter terminal of one NPN bipolar transistor of said first inverter is electrically coupled to a first bit line conductor, and the second emitter terminal of the NPN bipolar transistor of said second inverter device is electrically coupled to a second bit line.

A method of forming a complementary lateral bipolar SRAM device. The device includes: a first set and second set of lateral bipolar transistors forming a respective first inverter device and second inverter device, the first and second inverter devices being cross-coupled for storing a logic state. In each said first and second set, a first bipolar transistor is an PNP type bipolar transistor, and a second bipolar transistor is an NPN type bipolar transistor, each said NPN type bipolar transistor having a base terminal, a first emitter terminal, a second emitter terminal, and a collector terminal. Emitter terminals of the PNP type transistors of each first and second inverter devices are electrically coupled together and receive a first applied wordline voltage. The first emitter terminals of each said NPN transistors of said first inverter and second inverter devices are electrically coupled together and receive a second applied voltage. The second emitter terminal of one NPN bipolar transistor of said first inverter is electrically coupled to a first bit line conductor, and the second emitter terminal of the NPN bipolar transistor of said second inverter device is electrically coupled to a second bit line.

A two transistor ternary random access memory (TTTRAM) circuit includes an voltage/current input, an input/output switch, a first transistor, a first pull up resistor, a second transistor, and a second pull up resistor. The first transistor has a first emitter, a first collector connected to the input/output switch, and a first base. The first pull up resistor is connected to the first emitter and the voltage/current input. The second transistor has a second emitter connected to ground, a second collector, and a second base connected to the input/output switch. The second pull up resistor is connected to the first base, the second collector, and the voltage/current input.