摘要:
A method for forming a ferroelectric material film, more particularly a lead zirconate titanate (PZT) film by the sol-gel method wherein a lowered oxidative sintering temperature may be adopted in preparing the ferroelectric material film with a perovskite crystalline structure, thereby reducing the risk of oxidation of metal electrodes and other circuits when the ferroelectric material film is employed as a dielectric in semiconductor devices, such as in a capacitor, for example. The method contemplates the preparation of a raw material solution containing an organometallic compound of a metallic element forming the ferroelectric material film, alkanolamine and/or stabilizer comprising a .beta.-diketone, with the concentration of the stabilizer being sufficient to provide a mole ratio to the total metal atoms of (stabilizer/total metal atoms)>3. The method then involves coating the raw material solution, drying the coated raw material solution to form a dried film, and sintering the dried film to form the ferroelectric material film wherein the oxidative sintering is carried out at a relatively low temperature of about 450.degree. C. in forming the ferroelectric material film with a perovskite crystalline structure.
摘要:
A capacitor, electrode, or wiring structure having an alpha ray emitting source (in particular, a Pt electrode), and an alpha ray shielding layer 18, having at least one type selected from the group of simple metals of nickel, cobalt, copper, and tungsten, their compounds or alloys made of at least two types of these simple metals, and compounds and alloys made of these simple metals and silicon is provided. It is possible to shield off the alpha ray effectively, to suppress generation of soft errors, to enable the use of Pt and other new materials in making the electrodes and wiring, and to reduce the cost of the mold resin.
摘要:
A dielectric capacitor is provided which has a reduced leakage current. The surface of a first electrode (38) of the capacitor is electropolished and a dielectric film (40) and a second electrode (37) are successively laminated on it. The convex parts pointed end (38a) existing on the surface of the first electrode is very finely polished uniformly by dissolving according to electropolishing, a spherical curved surface in which the radius of curvature has been enlarged is formed, and the surface of the first electrode is flattened. Therefore, concentration of electrolysis can be prevented during the operation at the interface of the first electrode and the dielectric film, and the leakage current can be reduced considerably.
摘要:
A ferroelectric memory structure is described for the 1T1C arrangement in a ferroelectric capacitor cell array for FeRAM memory device applications. The device structure provides an accurate reference voltage and a simple sensing scheme for the sense amplifier used for reading the state of a target memory cell of the FeRAM array. A reference circuit generates a reference voltage which is a function of a charge shared between a plurality of FeRAM dummy cells. Each dummy cell of the plurality of FeRAM dummy cells is selectively coupleable to a plurality of bitlines. A shorting transistor in the reference circuit couples two bitlines or two bitline-bars neighboring the selected target memory cell. One dummy cell is coupled to a select one of the two shorted bitlines or bitline-bars, and another dummy cell is coupled to a another of the two shorted bitlines or bitline-bars, wherein at least one dummy cell is biased to a “0” state, and at least one other dummy cell is biased to a “1” state. As charge sharing takes place between the bias states of the dummy cells and the shorted bitlines, an averaged reference voltage is produced which is substantially centered between the “0” or “1” states. A sense amplifier receives a sense signal from the target memory cell on an associated bitline, and the averaged reference voltage is received on another bitline input of the sense amplifier. Thus, a new ferroelectric memory structure provides a centered reference voltage and a simple sensing scheme for the accurate sensing of the logic state of an FeRAM 1T1C cell for a read operation.
摘要:
To provide a method that can be used to form a high-qualility ferroelectric film by forming good nuclei when using the sputtering method to manufacture a PZT capacitor or other forroelectric capacitors using Ir or other electrode substances in addition to Pt for the electrode. In the method for manufacturing a PZT ferroelectric capacitor CAP, after titanium film 31 is deposited on Ir electrode 6, lead oxide 32 is deposited at a substrate temperature higher than the crystallization temperature of lead titanate using the sputtering method. Lead zirconate titanate 34 is then deposited at a substrate temperature higher than the aforementioned substrate temperature using the sputtering temperature. Afterwards, a heat treatment of the deposited film is performed to produce PZT film 17.
摘要:
A metal oxide capacitor is manufactured by sequentially laminating a metal oxide film and a secon electrode on a first electrode. The metal oxide film is formed and then heat-treated in an atmosphere with an oxygen pressure higher than 1 atm.
摘要:
A ferroelectric memory structure is described for the 1T1C arrangement in a ferroelectric capacitor cell array for FeRAM memory device applications. The device structure provides an accurate reference voltage and a simple sensing scheme for the sense amplifier used for reading the state of a target memory cell of the FeRAM array. A reference circuit generates a reference voltage which is a function of a charge shared between a plurality of FeRAM dummy cells. Each dummy cell of the plurality of FeRAM dummy cells is selectively coupleable to a plurality of bitlines. A shorting transistor in the reference circuit couples two bitlines or two bitline-bars neighboring the selected target memory cell. One dummy cell is coupled to a select one of the two shorted bitlines or bitline-bars, and another dummy cell is coupled to a another of the two shorted bitlines or bitline-bars, wherein at least one dummy cell is biased to a “0” state, and at least one other dummy cell is biased to a “1” state. As charge sharing takes place between the bias states of the dummy cells and the shorted bitlines, an averaged reference voltage is produced which is substantially centered between the “0” or “1” states. A sense amplifier receives a sense signal from the target memory cell on an associated bitline, and the averaged reference voltage is received on another bitline input of the sense amplifier. Thus, a new ferroelectric memory structure provides a centered reference voltage and a simple sensing scheme for the accurate sensing of the logic state of an FeRAM 1T1C cell for a read operation.
摘要:
A ferroelectric memory structure is described for the 1T1C arrangement in a ferroelectric capacitor cell array for FeRAM memory device applications. The device structure provides an accurate reference voltage and a simple sensing scheme for the sense amplifier used for reading the state of a target memory cell of the FeRAM array. A reference circuit generates a reference voltage which is a function of a charge shared between a plurality of FeRAM dummy cells. Each dummy cell of the plurality of FeRAM dummy cells is selectively coupleable to a plurality of bitlines. A shorting transistor in the reference circuit couples two bitlines or two bitline-bars neighboring the selected target memory cell. One dummy cell is coupled to a select one of the two shorted bitlines or bitline-bars, and another dummy cell is coupled to a another of the two shorted bitlines or bitline-bars, wherein at least one dummy cell is biased to a “0” state, and at least one other dummy cell is biased to a “1” state. As charge sharing takes place between the bias states of the dummy cells and the shorted bitlines, an averaged reference voltage is produced which is substantially centered between the “0” or “1” states. A sense amplifier receives a sense signal from the target memory cell on an associated bitline, and the averaged reference voltage is received on another bitline input of the sense amplifier. Thus, a new ferroelectric memory structure provides a centered reference voltage and a simple sensing scheme for the accurate sensing of the logic state of an FeRAM 1T1C cell for a read operation.
摘要:
A ferroelectric memory structure is described for the 1T1C arrangement in ferroelectric capacitor cell array for FeRAM memory device applications. The device structure provides an accurate reference voltage and a simple sensing scheme for the sense amplifier used for reading the state of a target memory cell of the FeRAM array. A reference circuit generates a reference voltage which is a function of a charge shared between a plurality of FeRAM dummy cells. Each dummy cell of the plurality of FeRAM dummy cells is selectively coupleable to a plurality of bitlines. A shorting transistor in the reference circuit couples two bitlines or two bitline-bars neighboring the selected target memory cell. One dummy cell is coupled to a select one of the two shorted bitlines or bitline-bars, and another dummy cell is coupled to a another of the two shorted bitlines or bitline-bars, wherein at least one dummy cell is biased to a “0” state, and at least one other dummy cell is biased to a “1” state. As charge sharing takes place between the bias states of the dummy cells and the shorted bitlines, an averaged reference voltage is produced which is substantially centered between the “0” or “1” states. A sense amplifier receives a sense signal from the target memory cell on an associated bitline, and the averaged reference voltage is received on another bitline input of the sense amplifier. Thus, a new ferroelectric memory structure provides a centered reference voltage and a simple sensing scheme for the accurate sensing of the logic state of an FeRAM 1T1C cell for a read operation.
摘要:
A capacitor and electrode structure comprising a PZT ferroelectric layer 17 with a primary component (Pb) and secondary component (Ti), a lower electrode layer 16 formed on the underside of the ferroelectric layer and made up of a special element (Pt) and Ti, and compounds thereof, and a diffusion barrier layer 18 which is formed on the underside of the lower electrode layer and which functions as a diffusion barrier with respect to Pb. The capacitor and the electrode structure, which may be a component of a semiconductor memory device, suppress fluctuations in the composition of the ferroelectric layer in PZT, etc., so as to maintain the intended performance of the PZT ferroelectric layer, thereby simplifying and stabilizing film fabrication, and preventing the degradation of electrical characteristics and adverse effects on lower layers.