Kepler Computing Inc.

The disclosed technology generally relates to ferroelectric materials and semiconductor devices, and more particularly to semiconductor memory devices incorporating doped polar materials. In one aspect, a semiconductor device comprises a capacitor which in turn comprises a polar layer comprising a base polar material doped with a dopant. The base polar material includes one or more metal elements and one or both of oxygen or nitrogen. The dopant comprises a metal element that is different from the one or more metal elements and is present at a concentration such that a ferroelectric switching voltage of the capacitor is different from that of the capacitor having the base polar material without being doped with the dopant by more than about 100 mV. The capacitor stack additionally comprises first and second crystalline conductive oxide electrodes on opposing sides of the polar layer. The capacitor stack further comprises first and second barrier metal layers on respective ones of the first and second crystalline conductive oxide electrodes on opposing sides of the polar layer.

The disclosed technology generally relates to ferroelectric materials and semiconductor devices, and more particularly to semiconductor memory devices incorporating doped polar materials. In one aspect, a semiconductor device comprises a capacitor which in turn comprises a polar layer comprising a base polar material doped with a dopant. The base polar material includes one or more metal elements and one or both of oxygen or nitrogen. The dopant comprises a metal element that is different from the one or more metal elements and is present at a concentration such that a ferroelectric switching voltage of the capacitor is different from that of the capacitor having the base polar material without being doped with the dopant by more than about 100 mV. The capacitor stack additionally comprises first and second crystalline conductive oxide electrodes on opposing sides of the polar layer. The capacitor stack further comprises first and second barrier metal layers on respective ones of the first and second crystalline conductive oxide electrodes on opposing sides of the polar layer.

A low power sequential circuit (e.g., latch) uses a non-linear polar capacitor to retain charge with fewer transistors than traditional CMOS sequential circuits. In one example, a sequential circuit includes pass-gates and inverters, but without a feedback mechanism or memory element. In another example, a sequential uses load capacitors (e.g., capacitors coupled to a storage node and a reference supply). The load capacitors are implemented using ferroelectric material, paraelectric material, or linear dielectric. In one example, a sequential uses minority, majority, or threshold gates with ferroelectric or paraelectric capacitors. In one example, a sequential circuit uses minority, majority, or threshold gates configured as NAND gates.

An adder with first and second majority gates. For a 1-bit adder, output from a 3-input majority gate is inverted and input two times to a 5-input majority gate. Other inputs to the 5-input majority gate are same as those of the 3-input majority gate. The output of the 5-input majority gate is a sum while the output of the 3-input majority gate is the carry. Multiple 1-bit adders are concatenated to form an N-bit adder. The input signals are driven to first terminals of non-ferroelectric capacitors while the second terminals are coupled to form a majority node. Majority function of the input signals occurs on this node. The majority node is then coupled to a first terminal of a non-linear polar capacitor. The second terminal of the capacitor provides the output of the logic gate. A reset mechanism initializes the non-linear polar capacitor before addition function is performed.

The disclosed technology generally relates to ferroelectric materials and semiconductor devices, and more particularly to semiconductor memory devices incorporating doped polar materials. In one aspect, a semiconductor device comprises a capacitor which in turn comprises a polar layer comprising a base polar material doped with a dopant. The base polar material includes one or more metal elements and one or both of oxygen or nitrogen. The dopant comprises a metal element that is different from the one or more metal elements and is present at a concentration such that a ferroelectric switching voltage of the capacitor is different from that of the capacitor having the base polar material without being doped with the dopant by more than about 100 mV. The capacitor stack additionally comprises first and second crystalline conductive oxide electrodes on opposing sides of the polar layer. The capacitor stack further comprises first and second barrier metal layers on respective ones of the first and second crystalline conductive oxide electrodes on opposing sides of the polar layer.

Endurance mechanisms are introduced for memories such as non-volatile memories for broad usage including caches, last-level cache(s), embedded memory, embedded cache, scratchpads, main memory, and storage devices. Here, non-volatile memories (NVMs) include magnetic random-access memory (MRAM), resistive RAM (ReRAM), ferroelectric RAM (FeRAM), phase-change memory (PCM), etc. In some cases, features of endurance mechanisms (e.g., randomizing mechanisms) are applicable to volatile memories such as static random-access memory (SRAM), and dynamic random-access memory (DRAM). The endurance mechanisms include a wear leveling scheme that uses index rotation, outlier compensation to handle weak bits, and random swap injection to mitigate wear out attacks.

A new class of logic gates are presented that use non-linear polar material. The logic gates include multi-input majority gates. Input signals in the form of digital signals are driven to non-linear input capacitors on their respective first terminals. The second terminals of the non-linear input capacitors are coupled a summing node which provides a majority function of the inputs. The majority node is then coupled driver circuitry which can be any suitable logic gate such as a buffer, inverter, NAND gate, NOR gate, etc. In the multi-input majority or minority gates, the non-linear charge response from the non-linear input capacitors results in output voltages close to or at rail-to-rail voltage levels. Bringing the majority output close to rail-to-rail voltage eliminates the high leakage problem faced from majority gates formed using linear input capacitors.

A new class of logic gates are presented that use non-linear polar material. The logic gates include multi-input majority gates. Input signals in the form of digital signals are driven to non-linear input capacitors on their respective first terminals. The second terminals of the non-linear input capacitors are coupled a summing node which provides a majority function of the inputs. The majority node is then coupled driver circuitry which can be any suitable logic gate such as a buffer, inverter, NAND gate, NOR gate, etc. In the multi-input majority or minority gates, the non-linear charge response from the non-linear input capacitors results in output voltages close to or at rail-to-rail voltage levels. Bringing the majority output close to rail-to-rail voltage eliminates the high leakage problem faced from majority gates formed using linear input capacitors.

The disclosed technology generally relates to ferroelectric materials and semiconductor devices, and more particularly to semiconductor memory devices incorporating doped polar materials. In one aspect, a semiconductor device comprises a capacitor which in turn comprises a polar layer comprising a base polar material doped with a dopant. The base polar material includes one or more metal elements and one or both of oxygen or nitrogen. The dopant comprises a metal element that is different from the one or more metal elements and is present at a concentration such that a ferroelectric switching voltage of the capacitor is different from that of the capacitor having the base polar material without being doped with the dopant by more than about 100 mV. The capacitor stack additionally comprises first and second crystalline conductive oxide electrodes on opposing sides of the polar layer. The capacitor stack further comprises first and second barrier metal layers on respective ones of the first and second crystalline conductive oxide electrodes on opposing sides of the polar layer

The disclosed technology generally relates to ferroelectric materials and semiconductor devices, and more particularly to semiconductor memory devices incorporating doped polar materials. In one aspect, a semiconductor device comprises a capacitor, which in turn comprises a polar layer comprising a crystalline base polar material doped with a dopant. The base polar material includes one or more metal elements and one or both of oxygen or nitrogen, wherein the dopant comprises a metal element that is different from the one or more metal elements and is present at a concentration such that a ferroelectric switching voltage of the capacitor is different from that of the capacitor having the base polar material without being doped with the dopant by more than about 100 mV. The capacitor additionally comprises first and second crystalline conductive or semiconductive oxide electrodes on opposing sides of the polar layer, wherein the polar layer has a lattice constant that is matched within about 20% of a lattice constant of one or both of the first and second crystalline conductive or semiconductive oxide electrodes. The first crystalline conductive or semiconductive oxide electrode serves as a template for growing the polar layer thereon, such that at least a portion of the polar layer is pseudomorphically formed on the first crystalline conductive or semiconductive oxide electrode.