24results about How to "Improve ferroelectric properties" patented technology

The invention discloses a doped hafnium oxide-based ferroelectric film based on doping distribution regulation and control and a preparation method and application thereof, an x-y-x structural unit is selected according to the doping concentration, an ALD technology is repeatedly adopted on a substrate to obtain [(Hf0. 5Zr0. 5O2) y-Alx-(Hf0. 5Zr0. 5O2) y] z ferroelectric films with different doping concentrations, x is the number of cycles of a dopant, y is the number of cycles of the dopant, y is the number of cycles of the dopant, y is the number of cycles of the dopant, y is the number of cycles of the dopant, and z is the number of cycles of the dopant. Y is the total number of cycles of hafnium oxide and zirconium oxide, z is the number of repetitions of an x-y-x structural unit, and the doping concentration of the ferroelectric film is x / 2y; a top electrode and a bottom electrode are plated on a [(Hf < 0.5 > Zr < 0.5 > O < 2 >) < y >-Al < x >-(Hf < 0.5 > Zr < 0.5 > O < 2 >) < y >] < z > ferroelectric film, and then high-temperature annealing treatment is performed to obtain the doped hafnium oxide-based ferroelectric film based on doping distribution regulation and control. According to the invention, the distribution of doped elements is accurately regulated and controlled, so that the insulating property, ferroelectric property and durability of the material are remarkably improved, and the requirements of future high-performance electronic devices are met. The technical innovation opens up a new direction for application of ferroelectric materials and promotes further development of related fields.

The invention relates to an ultrathin hafnium oxide ferroelectric film capacitor based on electrode optimization and a preparation method thereof, and the method can effectively inhibit the production of an interface dead layer and excessive oxygen vacancies at the bottom of an HYO ferroelectric film through constructing a capacitor with a six-layer structure of a substrate, a bottom electrode layer, an oxide intercalation layer, a metal layer, an HYO ferroelectric film layer and a top electrode layer. The HYO ferroelectric film layer is grown through an atomic layer deposition method, and a large-area high-quality ferroelectric film with good uniformity can be grown; the capacitor with a six-layer structure is rapidly annealed in an inert atmosphere, so that the formation of a ferroelectric orthogonal phase in the HYO ferroelectric film can be promoted, the ferroelectricity is improved, the coercive field and the leakage current are reduced, and the fatigue characteristic is enhanced; meanwhile, the whole preparation process is simple and controllable, and the prepared ferroelectric film is good in quality and has commercial production and application potential.

The invention discloses a high-energy-storage high-entropy ceramic dielectric material based on barium titanate. The material has the following chemical composition: Ba0.2 [(K0. 5Na0. 5) Bi] x (SrCaMg) (2 / 3) (0.4-x) TiO3, and x is equal to 0.16 to 0.20. The high-entropy ceramic is constructed by introducing six A-site cations (K, Na, Bi, Sr, Ca and Mg) into BaTiO3, so that the structure of the high-entropy ceramic is optimized, and the energy storage performance of the high-entropy ceramic is improved. The introduced ions are divided into a ferroelectric phase group and a non-ferroelectric phase group according to ion characteristics, and the ferroelectric phase and the non-ferroelectric phase are relatively balanced. The material has a thin and narrow ferroelectric hysteresis loop and high breakdown field strength, and the energy storage performance is greatly improved on the premise of ensuring certain energy storage efficiency.

This application discloses a two-dimensional germanium-based perovskite ferroelectric semiconductor material, its preparation method, and its applications, belonging to the field of materials science. The molecular formula of the two-dimensional germanium-based perovskite ferroelectric semiconductor material is [CH3(CH2)]. n The molecule is NH3]2CsGe2I7, where n = 2, 3, or 4. This material possesses excellent physicochemical properties, such as semiconductor characteristics, ferroelectricity, and piezoelectricity. The preparation method of this invention allows for the preparation of this material using a simple solution method at low cost. This material has potential applications in ferroelectric, optoelectronic, and other fields.

The invention discloses a room-temperature ferroelectric material with an extremely low coercive field, a large spontaneous polarization value and a high Curie temperature and a preparation method and application thereof, the room-temperature ferroelectric material is a zero-dimensional organic-inorganic hybrid perovskite crystal material, has the following chemical formula (C2H8N) 4PbBr6, has the spontaneous polarization value of 2.3 [mu] C / cm < 2 > and the coercive field of 0.11 kV / cm, and has the Curie temperature of greater than 400 K, and the room-temperature ferroelectric material is a ferroelectric material with an extremely low coercive field, a large spontaneous polarization value and a high Curie temperature. Wide application prospects are realized in low-loss nonvolatile memories, sensors, capacitors, optical modulators, electromagnetic nondestructive testing and battery technologies.

The invention relates to the technical field of preparation of thin film materials, and particularly provides a BaTiO3 ferroelectric thin film with high energy storage at low temperature and a method and application of the BaTiO3 ferroelectric thin film. The preparation method of the BaTiO3 ferroelectric film comprises the following steps: processing a substrate, depositing a bottom electrode on the substrate, depositing a buffer layer on the bottom electrode, depositing a barium titanate dielectric layer on the buffer layer, and depositing a top electrode on the barium titanate dielectric layer. The step of depositing the buffer layer on the bottom electrode comprises the following steps of: adopting a LaNiO3 target material, keeping the temperature at 200 DEG C, and depositing the buffer layer on the substrate in a radio frequency or direct current magnetron sputtering mode; and the total film thickness of the buffer layer is 0-50nm. The problems that in the prior art, a barium titanate film prepared through an in-situ preparation method at the temperature of 200 DEG C is poor in performance, application requirements cannot be met, and the performance of a BaTiO3 ferroelectric film is regulated and controlled by the thickness of a buffer layer are solved.

The application discloses an iron-based barium sodium niobate ceramic material with high energy storage performance and a preparation method thereof. 4‑2x Sm 2x Na2Fe x Nb 10‑x O 30 , wherein 1<=x<=1.25. Barium carbonate, samarium oxide, sodium carbonate, ferrous oxide and niobium pentoxide are used as raw materials, and a standard solid-phase method is adopted to sinter the iron-based barium sodium niobate ceramic material. In the product formula, iron is used to replace niobium in the barium sodium niobate, which is lead-free, environment-friendly, rich in iron reserves and low in price, and is beneficial to control the cost of raw materials. In addition, the iron replacement is beneficial to enhance the relaxor ferroelectric performance of the material, can obtain a more slender hysteresis loop, and improves the energy storage efficiency of the material. The prepared ceramic material has few pores and cracks, high density, and the microstructure is obviously improved, the grain size is more fine and uniform, the ferroelectric polarization intensity and the breakdown field strength are significantly improved, the problem that the barium sodium niobate material is difficult to sinter is solved, and the ferroelectric performance and the energy storage performance are significantly improved.

The invention discloses a method for constructing a polarized bubble-shaped topological domain array. The method comprises the following steps: S1, depositing a calcium-doped bismuth ferrite film through a pulse laser deposition method; s2, turning over an out-of-plane polarization direction of the thin film by using an electric field surface of a PFM needle tip, constructing an out-of-plane single domain, and performing characterization; s3, carrying out one-time point writing in the surface writing area through the PFM needle point pulse voltage, overturning the polarization, and constructing an in-plane center domain; s4, performing secondary dot-writing in the dot-writing area through the PFM pinpoint pulse voltage, and overturning the polarization; and S5, changing the position of the PFM needle tip, repeating the steps S3 and S4, and constructing the bubble-shaped ferroelectric topological domain array. The method for preparing the film sample is simple and environment-friendly, the method for preparing the polarized bubble-shaped topological domain array is simple and easy to implement, and the obtained polarized topological domain array is high in density and good in stability. The invention has potential application value in the aspect of high-density ferroelectric memories.

The invention discloses an annealing-free ferroelectric film material and a device application thereof. The invention provides a lanthanum-doped hafnium zirconium oxide (La: HZO) ferroelectric material using atomic layer deposition. The crystallization temperature and ferroelectric characteristics of the material are regulated and controlled by adjusting the deposition temperature and the oxygen source pulse time; the lanthanum doping proportion is regulated and controlled to control the ferroelectric characteristic and the electric leakage characteristic of the gate dielectric, the ferroelectric material which does not need annealing and is high in remanent polarization intensity and durability is achieved, the requirement for the process temperature needed by the subsequent process is met, and the ferroelectric material can be perfectly compatible with the subsequent process of a modern integrated circuit. Based on the material, a high-performance FeFET and a storage circuit thereof can be realized, and a high-performance FeRAM and a storage circuit thereof can also be realized. Compared with other HfO2 materials needing to be annealed to realize ferroelectricity, the material has lower crystallization temperature, higher remanent polarization under the same thermal budget and smaller electric leakage.

The invention relates to the technical field of ferroelectric materials, in particular to a novel ZnMgO ferroelectric material and a preparation method thereof. The novel ZnMgO ferroelectric material comprises a substrate, a bottom conductive layer, a ZnMgO ferroelectric film layer and a top electrode which are tightly stacked from bottom to top in sequence, the crystal structure of ZnMgO is a single wurtzite crystal structure, and the content of Mg is 10-55%. The thickness of the bottom conducting layer is 50-200 nm, the thickness of the ZnMgO ferroelectric film layer is 100-800 nm, and the thickness of the top electrode is 50-300 nm. The method has the advantages that the ZnMgO ferroelectric material is grown on the metal substrate through molecular beam epitaxy (MBE) low-temperature epitaxy, the single wurtzite high-magnesium component and excellent ferroelectric performance are achieved, the method can be well compatible with a traditional semiconductor technology, and application of the ferroelectric material is promoted.

The invention discloses a preparation method of ferroelectric nano particles with surfaces rich in grain boundary and torsional strain, and relates to a preparation method of ferroelectric nano particles with ultrasonic response. The invention aims to solve the problem that the existing nano enzyme depends on tumor endogenous hydrogen peroxide in tumor treatment. The method comprises the following steps: 1, preparing a bismuth nitrate solution; 2, adding manganese nitrate tetrahydrate and potassium permanganate into the bismuth nitrate solution; and 3, adjusting the pH value, and then carrying out high-temperature reaction. The method is used for preparing the ferroelectric nanoparticles with the surfaces rich in grain boundary and torsional strain.

The invention provides a ferroelectric ceramic material with a large dielectric constant in a wide temperature range and a preparation method of the ferroelectric ceramic material. The ferroelectric ceramic material is prepared by laminating and compounding BZT-xBST ceramic blanks of six critical ferroelectric phase change components (x is 0.1, 0.2, 0.3, 0.4, 0.6 and 0.8) in a system of the ferroelectric ceramic material; the ferroelectric ceramic material is prepared by laminating and compounding six different components of BZT-xBST ceramic blanks, the high dielectric property is successfully realized in a wide temperature range of 5-55 DEG C, and the high dielectric constant (epsilon gt; 21448), the ferroelectric ceramic material can show excellent performance in various application scenes such as capacitors, sensors, energy storage devices and the like, and the blank area that the wide temperature range and the high dielectric constant of the existing ferroelectric ceramic material are difficult to obtain at the same time is filled.

The invention discloses a ferroelectric device processing method, a ferroelectric device and a ferroelectric memory, oxygen atoms are controlled to rapidly permeate into a lattice structure of a ferroelectric film under a supercritical condition, oxygen vacancies are effectively filled, deep oxidation repair can be realized in a low-temperature environment, the ferroelectric characteristic of the device is further improved, and the performance of the ferroelectric device is improved. The residual polarization intensity is increased, the durability of the ferroelectric device is effectively improved, the wake-up effect is relieved, and the data retention time is prolonged.

The invention provides a ferroelectric device of a hafnium oxide-based thin film based on interface engineering and a preparation method of the ferroelectric device. The structure of the ferroelectric device comprises a substrate, a strontium-doped hafnium oxide film located on the substrate and a top electrode located on the strontium-doped hafnium oxide film. The substrate is a niobium strontium titanate substrate, and an interface, connected with the strontium-doped hafnium oxide thin film, on the niobium strontium titanate substrate is a TiO2 stop layer. According to the method, the interface terminal (TiO2 terminal or SrO terminal) of the niobium strontium titanate substrate (NSTO) is accurately controlled, and the strontium-doped hafnium oxide film (HSO) is prepared at the TiO2 terminal, so that the high stability of the ferroelectric orthogonal phase of the HSO film is realized. Compared with the SrO terminal, the HSO interface of the TiO2 terminal can more effectively enhance the ferroelectricity in the HSO thin film, and the stable ferroelectricity can be realized even in the HSO thin film with the thickness of 5nm.

The invention provides a gate stack structure FeFET and a preparation method thereof, and belongs to the technical field of micro-nano electronics. The FeFET structure comprises a silicon substrate, a source laminated layer, a drain laminated layer, a gate metal electrode, a passivation layer and a contact metal electrode, the gate laminated layer comprises an aluminum oxide channel interface layer and a double-layer hafnium zirconium oxide ferroelectric layer, and a thin aluminum oxide middle interface layer is inserted between the double-layer ferroelectric layer to effectively inhibit continuous growth of crystal grains in the ferroelectric layer. A write pulse with a larger amplitude and a shorter width is applied to the gate region of the FeFET structure, so that the consistency and durability of the FeFET device are synergistically optimized; the preparation process of the FeFET is mature, can be quickly applied to large-scale circuit design of the FeFET, and has a wide application prospect.

The present invention belongs to the field of infrared sensor technology, and in particular to a pyroelectric sensor system combined with a thermoelectric cooling device and a preparation method thereof, wherein the pyroelectric sensor system comprises a pyroelectric sensor, a thermoelectric cooling device, and an aluminum heat sink, and the pyroelectric sensor is composed of a tube cap, a lens, a pyroelectric ceramic sensitive element, a circuit board, a base, a conductive gasket, a signal processing chip, and a pin, and the pyroelectric ceramic sensitive element is made of a lead-free pyroelectric ceramic material 0.99 (99.7% Na 0.5 Bi 0.5 TiO3‑0.3%Na 0.5 Bi 4.5 Ti4O 15 )-0.01MnCO3 was polarized. Compared with BNT-NBT, the BNT-NBT-Mn of the present invention has a higher room temperature pyroelectric coefficient of 7.58×10 ‑4 Cm ‑2 K ‑1 and a depolarization temperature of 182°C; and successfully prepared a pyroelectric sensor, whose response rate and detection rate can meet the application requirements; on this basis, continuous monitoring of the pyroelectric sensor was achieved by using temperature control of a thermoelectric cooler.

A method for forming a film comprising hafnium, zirconium and oxygen, the method comprising forming (100) a film by a cyclic vapor deposition process under the action of an electric field (13).

The invention discloses an iron-based sodium barium niobate ceramic material with high energy storage performance and a preparation method thereof, the composition of the iron-based sodium barium niobate ceramic material is Ba (4-2x) Sm (2x) Na2FexNb (10-x) O30, and x is greater than or equal to 1 and less than or equal to 1.25. Barium carbonate, samarium oxide, sodium carbonate, ferric oxide and niobium pentoxide are used as raw materials, and a standard solid-phase method is adopted for sintering to prepare the samarium-doped barium carbonate. According to the product formula, iron is selected to replace niobium in barium sodium niobate, the product is lead-free and environment-friendly, iron reserves are rich, the price is low, the cost of raw materials is favorably controlled, iron replacement is favorable for enhancing the relaxor ferroelectric property of the material, a slender ferroelectric hysteresis loop can be obtained, and the energy storage efficiency of the material is improved. The prepared ceramic material has the advantages of few pores and cracks, high density, obviously improved microstructure, finer and more uniform grain size, obviously improved ferroelectric polarization strength and obviously improved breakdown field strength, solves the problem that the barium sodium niobate material is difficult to sinter, and obviously improves the ferroelectric property and energy storage property.

The invention relates to a lead-free high Curie temperature piezoelectric ceramic material and a preparation method thereof, the chemical formula of the piezoelectric ceramic material is CaBi2Nb1.9 (M'xTa1-x) 0.1 O9, M'represents a first element, and x is more than 0 and less than or equal to 0.5; the ion radius of the first element is # imgabs0 # or # imgabs1 #. According to the invention, M'and Ta are doped into CBN, so that a pseudo-tetragonal phase structure is constructed, the transformation degree from an orthogonal phase to a tetragonal phase is increased, the piezoelectric constant of the piezoelectric ceramic material is improved while the piezoelectric ceramic material is ensured to have high Curie temperature, and in addition, the piezoelectric constant of the piezoelectric ceramic material is improved. Nb is partially replaced by M'and Ta, so that the distortion degree of an NbO6 hexahedron is increased, and the dielectric property and ferroelectric property of the piezoelectric ceramic material are improved.

The present invention relates to a hafnium oxide-based ferroelectric capacitor and a preparation method thereof. The ferroelectric capacitor includes, from bottom to top in sequence, a first bottom electrode (4), a second bottom electrode (5), a hafnium oxide-based ferroelectric thin film (6b), a first top electrode (7), a second top electrode (8), and a substrate (9) which are stacked layer by layer; the first bottom electrode (4) and the second top electrode (8) are conductive layers; the second bottom electrode (5) and the first top electrode (7) are electrodes. Both the second bottom electrode (5) and the first top electrode (7) are HfNx (0 < x ≤ 1.1), and the second bottom electrode (5) and the first top electrode (7) have the same thickness; the substrate includes: silicon, a CMOS addressing, selection, and logic control circuit (1), a metal electrode, and an interlayer dielectric (2). The ferroelectric capacitor of the present invention has good miniaturization and excellent ferroelectric properties.

According to the preparation method of the thin-film capacitor and the thin-film capacitor, an SBT seed layer is deposited on a substrate through an MOCVD technology, the uniformity and crystal orientation of a thin film are ensured, and therefore the ferroelectric performance and insulativity of the capacitor are improved; the thickness control and the high dielectric constant of the thin film are further ensured by combining the main film layer formed by a sol-gel spin coating process; the flexible inner electrode is deposited through magnetron sputtering, and the flexible dielectric layer of the ceramic substrate is superposed, so that the capacitor can still operate stably under the bending condition. And a staged annealing and rapid thermal annealing (RTA) mode is adopted, so that stress and defects in the film layer are effectively reduced, and the structural stability and long-term durability of the film are enhanced. And during packaging, a copper or silver electrode is used, and nickel plating and tin plating treatment is carried out, so that the conductivity and corrosion resistance of the electrode are improved, and the service life of the capacitor is prolonged.

The invention discloses an electrode-free constrained annealing hafnium oxide-based ferroelectric film and a preparation method and application thereof.Hf0. 5Zr0. 5O2 films with a set number of layers and an Al2O3 film are alternately deposited on a substrate through the ALD technology, Alx-(Hf0. 5Zr0. 5O2) y ferroelectric films with different doping concentrations are obtained, x represents the number of layers of Al2O3 deposited through ALD, and y represents the number of layers of Hf0. 5Zr0. 5O2 deposited through ALD; the obtained Al < x >-(Hf < 0.5 > Zr < 0.5 > O < 2 >) < y > ferroelectric film is subjected to high-temperature annealing, and an Al < x >-(Hf < 0.5 > Zr < 0.5 > O < 2 >) < y > ferroelectric film sample is obtained; and plating a top electrode and a bottom electrode on the obtained Alx-(Hf0. 5Zr0. 5O2) y ferroelectric film sample to obtain the hafnium oxide-based ferroelectric film. According to the invention, the performance of the annealed ferroelectric film without electrode constraint is improved, the understanding of the ferroelectric principle of the HfO2 film is deepened, and the development of the novel practical ferroelectric film field is promoted.

The invention relates to the technical field of semiconductor devices, and provides a ferroelectric transistor and a preparation method and application thereof.The preparation method of the ferroelectric transistor comprises the following steps that a semiconductor layer is formed on a substrate, after patterning and etching are completed through a photoetching technology, the semiconductor layer is thermally oxidized at a preset temperature, the semiconductor layer is converted into a ferroelectric layer in situ, and the ferroelectric layer is formed; forming a heterostructure of the two; then photoetching and exposing source and drain electrode patterns, depositing metal through electron beams or thermal evaporation, and finishing source and drain electrode patterning in combination with a Lift-off process; preparing a dielectric layer on the ferroelectric layer by an atomic layer deposition method; and finally, photoetching and exposing the pattern of the top electrode, and completing the preparation of the top electrode through evaporation and Lift-off processes. According to the method, an atomic-scale ultra-flat uniform interface is realized, the adverse effect of an interface defect state and a depolarization field on ferroelectric performance can be effectively inhibited, the device has the advantages of low working voltage, high fatigue resistance and high-speed response, meanwhile, the device has the advantages of low thermal budget, high process compatibility and high expandability, and the overall device is excellent in performance.

The invention relates to the field of ferroelectric tunnel junctions, and discloses a preparation method of a hafnium oxide-based ferroelectric tunnel junction. The method comprises the following steps: firstly, preparing a tungsten bottom electrode on a silicon wafer by adopting electron beam evaporation; depositing a zirconium-doped hafnium oxide ferroelectric film on the tungsten bottom electrode at a low temperature by adopting an atomic layer deposition method; then preparing an insulating layer cerium oxide by adopting magnetron sputtering; finally, preparing tungsten as a top electrode by electron beam evaporation; and performing rapid thermal annealing treatment on the thin film to obtain a target hafnium oxide-based ferroelectric tunnel junction with an MFIM structure. The ferroelectric tunnel junction with the high on-off ratio prepared by the method has excellent ferroelectricity, high on-off ratio and high rectification ratio at the same time.