An antifuse-type one time programming memory cell includes a select device, a following device and an antifuse transistor. A first terminal of the select device is connected with a bit line. A second terminal of the select device is connected with a first node. A select terminal of the select device is connected with a word line. A first terminal of the following device is connected with the first node. A second terminal of the following device is connected with a second node. A control terminal of the following device is connected with a following control line. A first drain/source terminal of the antifuse transistor is connected with the second node. A gate terminal of the antifuse transistor is connected with an antifuse control line. A second drain/source terminal of the antifuse transistor is in a floating state.

A memory cell formed on the surface of a p-well of a semiconductor substrate includes a drain region and a source region that are formed with a channel region therebetween; an insulating film that is formed to cover the channel region; a gate that is formed on the insulating film; sidewall spacers that are formed to be positioned at side surfaces of the gate and directly above the channel region; a salicide block film that is formed to cover a portion of the drain region, a portion of the source regio, the gat, and the sidewall spacers; a drain salicide layer and a source salicide layer that are formed at the salicide block film and on the drain region and the source region exposed from the salicide block film; and a nitride film that is formed to cover the salicide block film, the drain salicide layer, and the source salicide layer.

Memory devices, systems including memory devices, and methods of operating memory devices and systems are provided, in which at least a subset of a non-volatile memory array is configured to behave as read-only memory by not implementing erase or write commands. In one embodiment of the present technology, a memory device is provided, comprising a non-volatile memory array, and circuitry configured to store one or more addresses of the non-volatile memory array, to compare an address of a received command to the one or more addresses, and at least in part based on the comparison, determine not to implement the received command. The circuitry can be further configured to return an error message after determining not to implement the received command.

Memory devices, systems including memory devices, and methods of operating memory devices and systems are provided, in which at least a subset of a non-volatile memory array is configured to behave as read-only memory by not implementing erase or write commands. In one embodiment of the present technology, a memory device is provided, comprising a non-volatile memory array, and circuitry configured to store one or more addresses of the non-volatile memory array, to compare an address of a received command to the one or more addresses, and at least in part based on the comparison, determine not to implement the received command. The circuitry can be further configured to return an error message after determining not to implement the received command.

A physically unclonable function (PUF) circuit includes a at least a PUF bit storage transistor. The at least a PUF bit storage transistor has a gate-to-source/drain breakdown voltage lower than a gate-to-channel breakdown voltage and a gated source/drain junction breakdown voltage.

A memory device is provided. The memory device includes a first transistor and a second transistor connected in series with the first transistor. The second transistor is programmable between a first state and a second state. A bit line connected to the second transistor. A sense amplifier connected to the bit line. The sense amplifier is operative to sense data from the bit line. A feedback circuit connected to the sense amplifier, wherein the feedback circuit is operative to control a bit line current of the bitline.

A memory device is provided. The memory device includes a first transistor and a second transistor connected in series with the first transistor. The second transistor is programmable between a first state and a second state. A bit line connected to the second transistor. A sense amplifier connected to the bit line. The sense amplifier is operative to sense data from the bit line. A feedback circuit connected to the sense amplifier, wherein the feedback circuit is operative to control a bit line current of the bitline.

A physically unclonable function (PUF) circuit includes a program control transistor, a program select transistor, a read select transistor, and a PUF bit storage transistor. The PUF bit storage transistor has a drain region coupled to the read select transistor, a source region coupled to a source line and the program select transistor, a channel region, a gate dielectric layer, and a gate electrode coupled to the program select transistor. The gate dielectric layer has a first portion formed on the drain region, a second portion formed on the source region, and a main portion formed on the channel region and between the first portion and the second portion, thicknesses of the first portion of the gate dielectric layer and the second portion of the gate dielectric layer being smaller than a thickness of the main portion of the gate dielectric layer.

A physically unclonable function (PUF) circuit includes a program control transistor, a program select transistor, a read select transistor, and a PUF bit storage transistor. The PUF bit storage transistor has a drain region coupled to the read select transistor, a source region coupled to a source line and the program select transistor, a channel region, a gate dielectric layer, and a gate electrode coupled to the program select transistor. The gate dielectric layer has a first portion formed on the drain region, a second portion formed on the source region, and a main portion formed on the channel region and between the first portion and the second portion, thicknesses of the first portion of the gate dielectric layer and the second portion of the gate dielectric layer being smaller than a thickness of the main portion of the gate dielectric layer.

A memory device is provided. The memory device includes a first transistor and a second transistor connected in series with the first transistor. The second transistor is programmable between a first state and a second state. A bit line connected to the second transistor. A sense amplifier connected to the bit line. The sense amplifier is operative to sense data from the bit line. A feedback circuit connected to the sense amplifier, wherein the feedback circuit is operative to control a bit line current of the bit-line.