A first amorphous film including hafnium, oxygen and a first element is formed, and a plurality of grains including a second element which differs from any of hafnium, oxygen and the first element is formed on the first amorphous film. An insulating film including a third element that differs from any of hafnium and the second element is formed over the plurality of grains and the first amorphous film, thereby forming a plurality of grains including the second element and the third element. A second amorphous film including the same materials as those of the first amorphous film is formed on the plurality of grains and the first amorphous film. By performing heat treatment, the first amorphous film and the second amorphous film are crystallized to form a first ferroelectric film which is an orthorhombic and a second ferroelectric film which is an orthorhombic, respectively.

An operation method of a multi-bits read only memory includes a step of applying a gate voltage to a conductive gate, a first voltage to a first electrode, and a second voltage to a second electrode. The multi-bits read only memory of the present invention includes a substrate and a transistor structure with the conductive gate mounted between the first electrode and the second electrode, a first oxide located between the first electrode and the conductive gate, and a second oxide located between the second electrode and the conductive gate. The present invention creates an initial state wherein the transistor structure is not conducting, an intermediate state wherein the first oxide is punched through by the first voltage, and a fully opened state wherein both the first oxide and the second oxide are punched through. The aforementioned states allow storage of multiple bits on the read only memory.

An operation method of a multi-bits read only memory includes a step of applying a gate voltage to a conductive gate, a first voltage to a first electrode, and a second voltage to a second electrode. The multi-bits read only memory of the present invention includes a substrate and a transistor structure with the conductive gate mounted between the first electrode and the second electrode, a first oxide located between the first electrode and the conductive gate, and a second oxide located between the second electrode and the conductive gate. The present invention creates an initial state wherein the transistor structure is not conducting, an intermediate state wherein the first oxide is punched through by the first voltage, and a fully opened state wherein both the first oxide and the second oxide are punched through. The aforementioned states allow storage of multiple bits on the read only memory.

A hybrid memory structure including a substrate, a flash memory, a first resistive random access memory (RRAM), and a second RRAM is provided. The flash memory is located on the substrate. The flash memory includes a gate, a first doped region, and a second doped region. The gate is located on the substrate. The first doped region is located in the substrate on one side of the gate. The second doped region is located in the substrate on another side of the gate. The first RRAM is electrically connected to one of the gate, the first doped region, and the second doped region. The second RRAM is electrically connected to another of the gate, the first doped region, and the second doped region.

Various embodiments provide a flash memory with an improved gate structure and a method of creating the same. The flash memory includes a plurality of memory cells that include a memory gate, a selection gate, a gate dielectric layer, and a protective cap formed on an upper surface of the gate dielectric layer. The protective cap protects the gate dielectric layer, and prevents the memory and selection gates from being unintentionally electrically connected to each other by conductive material.

A semiconductor device includes: a stack structure including conductive patterns and insulating layers, which are alternately stacked; a channel structure penetrating the stack structure; and a memory layer penetrating the stack structure, the memory layer being disposed between the channel structure and the stack structure. The memory layer includes memory parts and dummy parts, which are alternately arranged. Each of the memory parts includes a first part between the insulating layers and a second part between the dummy parts. The first part of the memory parts have ferroelectricity.

A method of manufacturing a memory structure including the following steps is provided. A first pad layer is formed on a substrate. Isolation structures are formed in the first pad layer and the substrate. At least one shape modification treatment is performed on the isolation structures. Each shape modification treatment includes the following steps. A first etching process is performed on the first pad layer to reduce a height of the first pad layer and to form first openings exposing sidewalls of the isolation structures. After the first etching process is performed, a second etching process is performed on the isolation structures to modify shapes of the sidewalls of the isolation structures exposed by the first openings. The first pad layer is removed to form a second opening between two adjacent isolation structures.

Cu-based nanostructures have excellent catalytic, electronic, and plasmonic performance due to their unique chemical and physical properties. A range of Cu materials including foil, spherical nanoparticles, nanowires, and nanocubes have been explored for catalyzing CO.sub.2 electroreduction. However, practical application of the CO.sub.2 electroreduction reaction requires Cu catalysts hold a high percentage of exposed surface atoms for improved product selectivity. The present disclosure describes a high temperature reduction method to prepare Cu nanosheets with size range from about 40 nm to about 13 μm in a hydrophobic system. The purity of trioctyphosphine (TOP) plays an important role for shape-controlled synthesis of Cu nanosheets. The morphology evolution was investigated by adjusting the feeding molar ratio of TOP/Cu-tetradecylamine complex. The Cu nanosheets formed by the methods of the present disclosure have high surface area and stability in solution for more than three months. These Cu nanosheets have applications in reducing CO.sub.2 to fuels.

An example memory device includes a channel positioned between and electrically connecting a first diffusion region and a second diffusion region, and a tunnel dielectric layer, a multi-layer charge trapping layer, and a blocking dielectric layer disposed between the gate structure and the channel. The multi-layer charge trapping layer includes a first dielectric layer disposed abutting a second dielectric layer and an anti-tunneling layer disposed between the first and second dielectric layers. The anti-tunneling layer includes an oxide layer. The first dielectric layer includes oxygen-rich nitride and the second dielectric layer includes oxygen-lean nitride.

An embedded flash memory device includes a gate stack, which includes a bottom dielectric layer extending into a recess in a semiconductor substrate, and a charge storage layer over the bottom dielectric layer. The charge storage layer includes a portion in the recess. The gate stack further includes a top dielectric layer over the charge storage layer, and a metal gate over the top dielectric layer. Source and drain regions are in the semiconductor substrate, and are on opposite sides of the gate stack.