Ferroelectric Nonvolatile Memory Structures (epo) Patents (Class 257/E21.663)
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Patent number: 7629183Abstract: A method for fabricating a semiconductor device includes the steps of forming a PbTiOx film having a predominantly (111) orientation on a lower electrode as a nucleation layer by an MOCVD process with a film thickness exceeding 2 nm, and forming a PZT film having a predominantly (111) orientation on the nucleation layer, wherein the step of forming the PbTiOx film is conducted under an oxygen partial pressure of less than 340 Pa.Type: GrantFiled: June 12, 2006Date of Patent: December 8, 2009Assignee: Tokyo Electron LimitedInventors: Kenji Matsumoto, Masayuki Nasu, Tomoyuki Sakoda
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Patent number: 7622346Abstract: A ferroelectric capacitor formation method necessary for stably fabricating an FeRAM and a semiconductor device fabrication method. After a PZT film is deposited on a lower electrode layer, the PZT film is crystallized by performing heat treatment in an atmosphere of a mixed gas which contains O2 gas and Ar gas. In this case, the flow rate of the O2 gas is controlled by one mass flow controller. The flow rate of the Ar gas used for purging and the flow rate of the Ar gas used for adjusting O2 gas concentration are controlled by different mass flow controllers. Before raising the temperature, the O2 gas, the Ar gas used for purging, and the Ar gas used for adjusting O2 gas concentration are made to flow at predetermined flow rates. Only the Ar gas used for purging is stopped, raising the temperature is begun, and the heat treatment is performed. At this time the O2 gas and the Ar gas used for adjusting O2 gas concentration flow at the predetermined flow rates.Type: GrantFiled: June 20, 2006Date of Patent: November 24, 2009Assignee: Fujitsu Microelectronics LimitedInventors: Mitsushi Fujiki, Katsuyoshi Matsuura, Genichi Komuro
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Publication number: 20090280578Abstract: A ferroelectric memory device includes a field effect transistor formed on a semiconductor substrate, an interlayer insulation film formed on the semiconductor substrate so as to cover the field effect transistor, a conductive plug formed in the interlayer insulation film in contact with the first diffusion region, and a ferroelectric capacitor formed over the interlayer insulation in contact with the conductive plug, wherein the ferroelectric capacitor includes a ferroelectric film and upper and lower electrodes sandwiching the ferroelectric film respectively from above and below, the lower electrode being connected electrically to the conductive plug, a layer containing oxygen being interposed between the conductive plug and the lower electrode, a layer containing nitrogen being interposed between the layer containing oxygen and the lower electrode, a self-aligned layer being interposed between the layer containing nitrogen and the lower electrode.Type: ApplicationFiled: July 14, 2009Publication date: November 12, 2009Applicant: FUJITSU MICROELECTRONICS LIMITEDInventor: Naoya SASHIDA
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Patent number: 7611911Abstract: A method (and resulting structure) of patterning a magnetic thin film, includes using a chemical transformation of a portion of the magnetic thin film to transform the portion to be non-magnetic and electrically insulating.Type: GrantFiled: October 8, 2003Date of Patent: November 3, 2009Assignee: International Business Machines CorporationInventors: David William Abraham, Eugene John O'Sullivan
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Patent number: 7579640Abstract: A hybrid memory device includes a plurality of regions including a memory cell array region upon which are formed a plurality of memory cells and a logic circuit region upon which is formed a logic circuit device, and is provided with a liner oxide layer formed on a region covering the logic circuit region except the memory cell array region and a cover layer formed on the liner oxide layer while extending to the memory cell array region.Type: GrantFiled: September 19, 2005Date of Patent: August 25, 2009Assignee: Oki Semiconductor Co., Ltd.Inventors: Yoko Kajita, Ichiro Koiwa, Takao Kanehara, Kinya Ashikaga, Kazuhide Abe
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Patent number: 7563667Abstract: In a method for forming a semiconductor device, a device isolation layer is formed in a capacitor region of a silicon substrate, and a bottom electrode and a dielectric layer are formed on the device isolation layer. Insulation sidewalls are formed on both sides of the bottom electrode. A top electrode is formed on the dielectric layer, and simultaneously a gate electrode is formed in a transistor region of the silicon substrate. Source/drain impurity regions are formed in the silicon substrate at both sides of the gate electrode.Type: GrantFiled: December 13, 2007Date of Patent: July 21, 2009Assignee: Dongbu HiTek Co., Ltd.Inventors: Choul Joo Ko, Yong Jun Lee
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Publication number: 20090166602Abstract: A phase-change memory device and a method of manufacturing the same, wherein the phase-change memory device includes a semiconductor substrate having a switching device, a phase-change layer formed on the semiconductor substrate having the switching device to change a phase thereof as the switching device is driven, and a bottom electrode contact in contact with the switching device through a first contact area and in contact with the phase-change layer through a second contact area, which is smaller than the first contact area.Type: ApplicationFiled: July 8, 2008Publication date: July 2, 2009Applicant: HYNIX SEMICONDUCTOR, INC.Inventor: Kyong-Soo Kum
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Patent number: 7535745Abstract: A ferroelectric memory device, which includes a vertical ferroelectric capacitor having an electrode distance smaller than a minimum feature size of lithography technology being used and suitable for the miniaturization, and a method of manufacturing the same are disclosed. According to one aspect of the present invention, it is provided a ferroelectric memory device comprising an MIS transistor formed on a substrate, and a ferroelectric capacitor formed on an interlevel insulator above the MIS transistor, wherein a pair of electrodes of the ferroelectric capacitor are disposed in a channel length direction of the MIS transistor to face each other putting a ferroelectric film in-between, and wherein a distance between the electrodes of the ferroelectric capacitor is smaller than a gate length of the MIS transistor.Type: GrantFiled: June 19, 2006Date of Patent: May 19, 2009Assignee: Kabushiki Kaisha ToshibaInventor: Susumu Shuto
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Patent number: 7527985Abstract: A method for manufacturing a memory device comprises patterning a dielectric layer and a conductive layer to align near the center of the top surface of a first contact drain plug and near the center of the top surface of a second contact drain plug. A first electrode is formed on the right sidewalls of the patterned dielectric layer and the conductive layer. A sidewall insulating member has a first sidewall surface and a second sidewall surface where the first sidewall surface of the sidewall insulating member is in contact with a sidewall of the first electrode. A second electrode is formed by depositing an electrode layer overlying the top surface of the sidewall insulating member and the second sidewall of the insulating member and isotropically etching the electrode layer to form the second electrode.Type: GrantFiled: October 24, 2006Date of Patent: May 5, 2009Assignee: Macronix International Co., Ltd.Inventors: Erh-Kun Lai, ChiaHua Ho, Kuang Yeu Hsieh
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Patent number: 7521743Abstract: Disclosed is a nonvolatile magnetic memory device including a magntoresistance device having a recording layer formed of a ferromagnetic material for storing information by use of variation in resistance depending on the magnetization inversion state. The plan-view shape of the recording layer includes a pseudo-rhombic shape having four sides, at least two of the four sides each include a smooth curve having a central portion curved toward the center of the pseudo-rhombic shape. The easy axis of magnetization of the recording layer is substantially parallel to the longer axis of the pseudo-rhombic shape. The hard axis of magnetization of the recording layer is substantially parallel to the shorter axis of the pseudo-rhombic shape. The sides constituting the plan-view shape of the recording layer are smoothly connected to each other.Type: GrantFiled: June 8, 2005Date of Patent: April 21, 2009Assignee: Sony CorporationInventor: Hajime Yamagishi
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Publication number: 20090097299Abstract: A first electrode is formed on a stacked-layer film, which is formed of a ferroelectric layer and a semiconductor layer, at the ferroelectric layer and a plurality of second electrodes are formed on the stacked-layer film at the semiconductor layer side. Each of parts of the semiconductor layer located in regions in which the second electrodes are formed functions as a resistance modulation element (memory) using the polarization assist effect of the ferroelectric layer. Information (a low resistance state or a high resistance state) held in a memory is read by detecting a value of a current flowing in each part of the semiconductor layer. Information is written in a memory by inverting a polarization of the ferroelectric layer.Type: ApplicationFiled: September 12, 2008Publication date: April 16, 2009Inventors: Hiroyuki TANAKA, Yasuhiro SHIMADA, Yukihiro KANEKO
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Patent number: 7517702Abstract: A method for making an electronic device may include forming a poled superlattice comprising a plurality of stacked groups of layers and having a net electrical dipole moment. Each group of layers of the poled superlattice may include a plurality of stacked semiconductor monolayers defining a base semiconductor portion and at least one non-semiconductor monolayer thereon. The at least one non-semiconductor monolayer may be constrained within a crystal lattice of adjacent base semiconductor portions, and at least some semiconductor atoms from opposing base semiconductor portions may be chemically bound together through the at least one non-semiconductor monolayer therebetween. The method may further include coupling at least one electrode to the poled superlattice.Type: GrantFiled: December 21, 2006Date of Patent: April 14, 2009Assignee: MEARS Technologies, Inc.Inventors: Samed Halilov, Xiangyang Huang, Ilija Dukovski, Jean Augustin Chan Sow Fook Yiptong, Robert J. Mears, Marek Hytha, Robert John Stephenson
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Publication number: 20090039341Abstract: The present invention relates to non-volatile ferroelectric memory devices (30) comprising a transistor (22) and a capacitor (23), and more particularly to non-volatile electrically erasable programmable ferroelectric memory elements, and a method for processing such non-volatile ferroelectric memory devices (30). The method according to the invention comprises a limited number of mask steps because a gate dielectric layer of the transistor (22) and a dielectric layer of the capacitor (23) are made from the same organic or inorganic ferroelectric layer (14).Type: ApplicationFiled: November 29, 2004Publication date: February 12, 2009Inventors: Albert W. Marsman, Dagobert Michel De Leeuw, Gerwin Hermanus Gelinck
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Patent number: 7488609Abstract: A method of forming a barrier layer of a tunneling magnetoresistive (TMR) device by forming first and second MgO barrier layers by different sputtering methods, but in the same sputtering system module. A first magnesium-oxide (MgO) barrier layer is formed over one of the TMR device's ferromagnetic layers by a DC magnetron sputter deposition from an Mg target in an oxygen environment. In the same module, a second MgO barrier layer is formed over the first MgO film by an RF sputter deposition from an MgO target and in an environment free of oxygen. Prior to the formation of the first MgO barrier layer, an optional Mg protection layer can be deposited on the ferromagnetic layer and oxidized by a first optional oxygen treatment. After deposition of the first MgO barrier layer, a second optional oxygen treatment may be conducted. After deposition of the second MgO barrier layer, a second Mg protection layer may be deposited by DC sputter deposition, followed by an optional third oxygen treatment.Type: GrantFiled: November 16, 2007Date of Patent: February 10, 2009Assignee: Hitachi Global Storage Technologies Netherlands B.V.Inventors: Tsann Lin, Daniele Mauri
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Patent number: 7473565Abstract: A semiconductor device comprises a bottom electrode, a top electrode, and a dielectric film provided between the bottom electrode and the top electrode and made of a perovskite type ferroelectrics containing Pb, Zr, Ti and O, the dielectric film comprising a first portion formed of a plurality of crystal grains partitioned by grain boundaries having a plurality of directions.Type: GrantFiled: July 11, 2005Date of Patent: January 6, 2009Assignees: Kabushiki Kaisha Toshiba, Infineon Technologies AGInventors: Osamu Arisumi, Keitaro Imai, Koji Yamakawa, Bum-ki Moon
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Patent number: 7471551Abstract: The direction of magnetization of a reading ferromagnetic material 5R forming a spin filter when reading is the same as that of a pinned layer 1. In this case, a torque that works on the spin of a free layer 3 due to a spin polarized current becomes “zero.” When the element size is made small so as to improve the integration degree of the magnetic memory, according to the scaling law, the writing current can be made small. In the present invention, the resistance to the spin injection magnetization reversal due to a reading current is high, so that the magnitude of the writing current can be lowered.Type: GrantFiled: May 23, 2007Date of Patent: December 30, 2008Assignee: TDK CorporationInventor: Tohru Oikawa
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Publication number: 20080283888Abstract: A spin transistor includes a non-magnetic semiconductor substrate having a channel region, a first area, and a second area. The channel region is between the first and the second areas. The spin transistor also includes a first conductive layer located above the first area and made of a ferromagnetic material magnetized in a first direction; and a second conductive layer located above the second area and made of a ferromagnetic material magnetized in one of the first direction and a second direction that is antiparallel with respect to the first direction. The channel region introduces electron spin between the conductive layers. The spin transistor also includes a gate electrode located between the conductive layers and above the channel region; and a tunnel barrier film located between the non-magnetic semiconductor substrate and at least one of the conductive layers.Type: ApplicationFiled: July 8, 2008Publication date: November 20, 2008Applicant: Kabushiki Kaisha ToshibaInventors: Yoshiaki SAITO, Hideyuki SUGIYAMA
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Patent number: 7449346Abstract: A method of manufacturing a ferroelectric thin film with good crystallinity and improved surface roughness includes: forming on a substrate a metal nitride-based precursor layer containing one selected from the group consisting of TiN, ZrxTi(1-x)N (0<x<1), FeN, and NbN; forming on the metal nitride-based precursor layer a mixed gas atmosphere containing oxygen (O2) and one reactive gas selected from the group consisting of PbO(g), Bi2O3(g), and K2O(g); annealing the metal nitride-based precursor layer in the mixed gas atmosphere and forming a ferroelectric thin film containing one selected from the group consisting of PbTiO3, PbZrxTi(1-x)O3 (0<x<1), Bi2Ti2O7, Bi4Ti3O12, BiFeO3, and KNbO3.Type: GrantFiled: September 8, 2006Date of Patent: November 11, 2008Assignee: Samsung Electronics Co., Ltd.Inventor: Simon Buehlmann
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Patent number: 7423283Abstract: Recesses are formed in the drain and source regions of an MOS transistor. An ohmic contact layer is formed in the recesses, and a stressed silicon-nitride layer is formed over the ohmic contact layer. The recesses allow the stressed silicon nitride layer to provide strain in the plane of the channel region. In a particular embodiment, a tensile silicon nitride layer is formed over recesses of an NMOS transistor in a CMOS cell, and a compressive silicon nitride layer is formed over recesses of a PMOS transistor in the CMOS cell. In a particular embodiment the stressed silicon nitride layer(s) is a chemical etch stop layer.Type: GrantFiled: June 7, 2005Date of Patent: September 9, 2008Assignee: XILINX, Inc.Inventors: Yuhao Luo, Deepak Kumar Nayak
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Patent number: 7402496Abstract: A complementary metal-oxide-semiconductor (CMOS) device includes a substrate with a first active region and a second active region; a first gate structure and a second gate structure, respectively disposed on the first active region and the second active region; a first spacer structure and a second spacer structure respectively disposed on sidewalls of the first gate structure and the second gate structure; a first LDD and a second LDD respectively disposed in the substrate at both sides of the first gate structure and the second gate structure; an epitaxial material layer, disposed in the first active region and located on a side of the first LDD; and a passivation layer, disposed on the first gate structure, the first spacer structure, and the first LDD and covering the second active region, wherein the passivation layer comprises a carbon-containing oxynitride layer.Type: GrantFiled: September 11, 2006Date of Patent: July 22, 2008Assignee: United Microelectronics Corp.Inventors: Che-Hung Liu, Po-Lun Cheng, Chun-An Lin, Li-Yuen Tang, Hung-Lin Shih, Ming-Chi Fan, Hsien-Liang Meng, Jih-Shun Chiang
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Patent number: 7400005Abstract: A semiconductor memory device, which prevents the penetration of hydrogen or moisture to a ferroelectric capacitor from its surrounding area including a contact plug portion, comprises a ferroelectric capacitor formed above a semiconductor substrate, a first hydrogen barrier film formed on an upper surface of the ferroelectric capacitor to work as a mask in the formation of the ferroelectric capacitor, a second hydrogen barrier film formed on the upper surface and a side face of the ferroelectric capacitor including on the first hydrogen barrier film, and a contact plug disposed through the first and second hydrogen barrier films, and connected to an upper electrode of the ferroelectric capacitor, a side face thereof being surrounded with the hydrogen barrier films.Type: GrantFiled: June 2, 2005Date of Patent: July 15, 2008Assignee: Kabushiki Kaisha ToshibaInventors: Yoshinori Kumura, Iwao Kunishima, Hiroyuki Kanaya, Tohru Ozaki, Kazuhiro Tomioka
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Patent number: 7394090Abstract: A non-volatile memory comprising: a first substrate (100) and a second substrate (110), the first substrate (100) having a plurality of switching elements (4) arranged in matrix, and a plurality of first electrodes (18) connected to the switching element (4), the second substrate (110) having a conductive film (32), and a recording layer (34) whose resistance value changes by application of an electric pulse, wherein the plurality of first electrodes (18) are integrally covered by the recording layer (34), the recording layer (34) thereby being held between the plurality of first electrodes (18) and the conductive film (32); the first substrate (100) further comprising a second electrode (22), the second electrode (22) being electrically connected to the conductive film (32), the voltage of which is maintained at a set level while applying current to the recording layer (34). This non-volatile memory achieves high integration at low cost.Type: GrantFiled: May 14, 2007Date of Patent: July 1, 2008Assignee: Matsushita Electric Industrial Co., Ltd.Inventors: Kiyoyuki Morita, Noboru Yamada, Akihito Miyamoto, Takashi Ohtsuka, Hideyuki Tanaka
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Patent number: 7390679Abstract: A method for manufacturing a ferroelectric capacitor, includes the steps of: forming a ferroelectric capacitor layer having a lower electrode layer, a ferroelectric layer and an upper electrode layer on a base substrate; forming a titanium oxide layer on the ferroelectric capacitor layer; patterning the titanium oxide layer by high-temperature etching between 200° C. and 500° C. to thereby form a mask pattern; and etching the ferroelectric capacitor layer by using the mask pattern as a mask, to thereby form a ferroelectric capacitor having a lower electrode, a ferroelectric film and an upper electrode.Type: GrantFiled: March 1, 2007Date of Patent: June 24, 2008Assignee: Seiko Epson CorporationInventor: Mamoru Miyaji
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Publication number: 20080142859Abstract: Methods and associated structures of forming a microelectronic device are described. Those methods may forming a conductive layer on a substrate, patterning the conductive layer, forming at least one nanodot on the patterned conductive layer, and forming a thin film ferroelectric material on the at least one nanodot.Type: ApplicationFiled: December 19, 2006Publication date: June 19, 2008Inventors: Qing Ma, Li-Peng Wang
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Patent number: 7368298Abstract: An Ir film, an IrOx film, a Pt film, a PtO film and a Pt film are formed, and thereafter a PLZT film is formed. Then, heat treatment at 600° C. or lower is performed by the RTA method in an atmosphere containing Ar and O2 to thereby crystallize the PLZT film. Subsequently, an IrOx film and an IrO2 film are formed. Then, these films are patterned at once. Thereafter, an alumina film is formed as a protective film. Subsequently, heat treatment at 650° C. for 60 minutes in an oxygen atmosphere is performed as recovery annealing. Note that no heat treatment is performed from the crystallization of the PLZT film to the recovery annealing.Type: GrantFiled: April 30, 2004Date of Patent: May 6, 2008Assignee: Fujitsu LimitedInventor: Wensheng Wang
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Patent number: 7323349Abstract: A method of fabricating resistor memory array includes preparing a silicon substrate; depositing a bottom electrode, a sacrificial layer, and a hard mask layer on a substrate P+ layer; masking, patterning and etching to remove, in a first direction, a portion of the hard mask, the sacrificial material, the bottom electrode; depositing a layer of silicon oxide; masking, patterning and etching to remove, in a second direction perpendicular to the first direction, a portion of the hard mask, the sacrificial material, the bottom electrode;, and over etching to an N+ layer and at least 100 nm of the silicon substrate; depositing of a layer of silicon oxide; etching to remove any remaining hard mask and any remaining sacrificial material; depositing a layer of CMR material; depositing a top electrode; applying photoresist, patterning the photoresist and etching the top electrode; and incorporating the memory array into an integrated circuit.Type: GrantFiled: May 2, 2005Date of Patent: January 29, 2008Assignee: Sharp Laboratories of America, Inc.Inventors: Sheng Teng Hsu, Jong-Jan Lee, Jer-Shen Maa, Douglas J. Tweet, Wei-Wei Zhuang
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Patent number: 7309617Abstract: The invention relates to a method for fabricating a reference layer for MRAM memory cells and an MRAM memory cell equipped with a reference layer of this type. A reference layer of this type comprises two magnetically coupled layers having a different Curie temperature. When cooling from a temperature above the Curie temperature TC1 of the first layer in an external magnetic field, the magnetization of the second layer is oriented by a second-order phase transition along the field direction of the external magnetic field. Upon further cooling below the Curie temperature TC2 of the second layer, the latter is oriented antiparallel with respect to the first layer as a result of the antiferromagnetic coupling between the two layers.Type: GrantFiled: March 11, 2003Date of Patent: December 18, 2007Assignee: Infineon Technologies AGInventors: Manfred Ruehrig, Ulrich Klostermann
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Patent number: 7297558Abstract: A W plug (24) is formed and a W oxidation preventing barrier metal film (25) is formed thereon. After that, an SiON film (27) thinner than the W oxidation preventing barrier metal film (25) is formed and Ar sputter etching is performed on the SiON film (27). As a result, the shape of the surface of the SiON film (27) becomes gentler and deep trenches disappear. Next, an SiON film (28) is formed on the whole surface. A voidless W oxidation preventing insulating film (29) is composed of the SiON (28) film and the SiON film (27).Type: GrantFiled: April 15, 2005Date of Patent: November 20, 2007Assignee: Fujitsu LimitedInventors: Yasutaka Ozaki, Tatsuya Yokota, Nobutaka Ohyagi
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Patent number: 7291505Abstract: The invention relates to a ferroelectric device (10) with a body (11) comprising a substrate (1) and a ferroelectric layer (2) provided with a connection conductor (3) on a side facing away from the substrate (1), which ferroelectric layer contains an oxygen-free ferroelectric material (2) and is used to form an active electrical element (4), in particular a memory element (4). Such a device forms an attractive non-volatile memory device. In accordance with the invention, a conductive layer (5) is present between the substrate (1) and the ferroelectric layer (2), which conductive layer forms a further connection conductor (5) of the ferroelectric layer (2), and the active electrical element (4) is obtained as a result of the fact that the ferroelectric layer (2) forms a Schottky junction with at least one of the connection conductors (3, 5).Type: GrantFiled: July 10, 2003Date of Patent: November 6, 2007Assignee: NXP B.V.Inventors: Paul Van Der Sluis, Martijn Henri Richard Lankhorst, Ronald Martin Wolf
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Publication number: 20070254383Abstract: A method of manufacturing a ferroelectric thin film with good crystallinity and improved surface roughness includes: forming on a substrate a metal nitride-based precursor layer containing one selected from the group consisting of TiN, ZrxTi(1-x)N (0<x<1), FeN, and NbN; forming on the metal nitride-based precursor layer a mixed gas atmosphere containing oxygen (O2) and one reactive gas selected from the group consisting of PbO(g), Bi2O3(g), and K2O(g); annealing the metal nitride-based precursor layer in the mixed gas atmosphere and forming a ferroelectric thin film containing one selected from the group consisting of PbTiO3, PbZrxTi(1-x)O3 (0<x<1), Bi2Ti2O7, Bi4Ti3O12, BiFeO3, and KNbO3.Type: ApplicationFiled: September 8, 2006Publication date: November 1, 2007Inventor: Simon Buehlmann
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Publication number: 20070176218Abstract: A dual-gate non-volatile memory cell includes a first dielectric layer extending over a first gate, a semiconductor region extending over the first dielectric layer, a second dielectric layer comprising tunnel oxide extending over the semiconductor region, a ferroelectric layer extending over the second dielectric layer, and a second gate extending over the ferroelectric layer.Type: ApplicationFiled: May 11, 2006Publication date: August 2, 2007Applicant: Hynix Semiconductor Inc.Inventor: Hee-Bok Kang
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Patent number: 7244981Abstract: A plurality of select gates are formed over a substrate. In one embodiment, the select gates are formed vertically on the sidewalls of trenches. The substrate includes a plurality of diffusion regions that are each formed between a pair of planar select gates. In a vertical embodiment, the diffusion regions are formed at the bottom of the trenches and the tops of the mesas formed by the trenches. An enriched region is formed in the substrate adjacent to and substantially surrounding each diffusion region in the substrate. Each enriched region has a matching conductivity type with the substrate. A gate insulator stack is formed over the substrate and each of the plurality of select gates. A word line is formed over the gate insulator stack.Type: GrantFiled: February 25, 2005Date of Patent: July 17, 2007Assignee: Micron Technology, Inc.Inventor: Arup Bhattacharyya
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Patent number: 7217969Abstract: A method of forming an integrated ferroelectric/CMOS structure which effectively separates incompatible high temperature deposition and annealing processes is provided. The method of the present invention includes separately forming a CMOS structure and a ferroelectric delivery wafer. These separate structures are then brought into contact with each and the ferroelectric film of the delivery wafer is bonded to the upper conductive electrode layer of the CMOS structure by using a low temperature anneal step. A portion of the delivery wafer is then removed providing an integrated FE/CMOS structure wherein the ferroelectric capacitor is formed on top of the CMOS structure. The capacitor is in contact with the transistor of the CMOS structure through all the wiring levels of the CMOS structure.Type: GrantFiled: March 7, 2003Date of Patent: May 15, 2007Assignee: International Business Machines CorporationInventors: James William Adkisson, Charles Thomas Black, Alfred Grill, Randy William Mann, Deborah Ann Neumayer, Wilbur David Pricer, Katherine Lynn Saenger, Thomas McCarroll Shaw
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Patent number: 7214977Abstract: A ferroelectric thin film formed of a highly oriented polycrystal in which 180° domains and 90° domains arrange at a constant angle to an applied electric field direction in a thin film plane and reversely rotate in a predetermined electric field.Type: GrantFiled: October 4, 2005Date of Patent: May 8, 2007Assignee: Seiko Epson CorporationInventors: Takeshi Kijima, Yasuaki Hamada, Eiji Natori
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Patent number: 7186573Abstract: A method of forming an integrated ferroelectric/CMOS structure which effectively separates incompatible high temperature deposition and annealing processes is provided. The method of the present invention includes separately forming a CMOS structure and a ferroelectric delivery wafer. These separate structures are then brought into contact with each and the ferroelectric film of the delivery wafer is bonded to the upper conductive electrode layer of the CMOS structure by using a low temperature anneal step. A portion of the delivery wafer is then removed providing an integrated FE/CMOS structure wherein the ferroelectric capacitor is formed on top of the CMOS structure. The capacitor is in contact with the transistor of the CMOS structure through all the wiring levels of the CMOS structure.Type: GrantFiled: October 31, 2005Date of Patent: March 6, 2007Assignee: International Business Machines CorporationInventors: James William Adkisson, Charles Thomas Black, Alfred Grill, Randy William Mann, Deborah Ann Neumayer, Wilbur David Pricer, Katherine Lynn Saenger, Thomas McCarroll Shaw
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Patent number: 7151001Abstract: A fabrication method of a self-aligned ferroelectric gate transistor using a buffer layer of high etching selectivity is disclosed. A stacked structure is formed with a buffer layer with high etching selectivity inserted between a silicon substrate and a ferroelectric layer, and etching is performed on a portion where a source and a drain will be formed and then stopped at the buffer layer, thereby fabricating a self-aligned ferroelectric gate transistor without damage to the silicon thin film, and thus, an integration degree of a chip can be improved.Type: GrantFiled: August 23, 2004Date of Patent: December 19, 2006Assignee: Korea Institute of Science and TechnologyInventors: Yong-Tae Kim, Seong-Il Kim, Chun-Keun Kim, Sun-Il Shim
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Patent number: 7132298Abstract: This disclosure relates to a system and method for creating nano-object arrays. A nano-object array can be created by exposing troughs in a corrugated surface to nano-objects and depositing the nano-objects within or orienting the nano-objects with the troughs.Type: GrantFiled: December 23, 2003Date of Patent: November 7, 2006Assignee: Hewlett-Packard Development Company, L.P.Inventors: Pavel Kornilovich, Peter Mardilovich, James Stasiak
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Patent number: 7109540Abstract: A method of manufacturing a semiconductor device is provided including: forming a groove in an insulation film; forming a lower electrode material film on the insulation film and in the groove; forming a ferroelectric material film on the lower electrode material film, on the insulation film and in the groove; forming an upper electrode material film on the ferroelectric material film, on the insulation film and in the groove; forming a capacitive element within the groove by removing the upper electrode material film and the ferroelectric material film from the insulation film and leaving the upper electrode material film and the ferroelectric material film within the groove by CMP-polishing the insulation film and the groove.Type: GrantFiled: November 9, 2004Date of Patent: September 19, 2006Assignee: Seiko Epson CorporationInventor: Toshihiko Higuchi
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Patent number: 7081380Abstract: A method of forming a conductive pattern of a semiconductor device includes forming a conductive layer is on a substrate, forming a polishing protection layer on the substrate including over the conductive layer, and forming a step compensation layer on the polishing protection layer to reduce the step presented by the layer that is the polishing protection layer. The conductive layer is the exposed by removing select portions of the step compensation layer and the polishing protection layer. The conductive pattern is ultimately formed on the substrate by etching the exposed conductive layer. By planarization the intermediate structure several times once the step compensation layer is formed, a highly uniform conductive layer is sure to be formed.Type: GrantFiled: February 23, 2004Date of Patent: July 25, 2006Assignee: Samsung Electronics Co., Ltd.Inventors: Don-Woo Lee, Chul-Soon Kwon, Chang-Yup Lee
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Patent number: 7034374Abstract: A common pinned layer is shared by multiple memory cells in an MRAM device. The common pinned layer includes a plurality of domain wall traps that prevent the formation of domain walls within a region of the common pinned layer corresponding to a given memory cell. Therefore, the memory cells can advantageously be formed such that the domain walls, to the extent they exist, fall between (rather than within) the memory cells, thereby improving the performance of the MRAM device.Type: GrantFiled: August 22, 2003Date of Patent: April 25, 2006Assignee: Micron Technology, Inc.Inventor: Joel A. Drewes
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Patent number: 7026677Abstract: The present invention provides a magnetic memory device capable of performing stable operation efficiently using a magnetic field generated by write current and formed with high precision while realizing a compact configuration. Since a plating film is used for at least a part of a magnetic yoke, as compared with the case of formation by a dry film forming method, sufficient thickness and higher dimensional precision can be obtained. Consequently, a more stabilized return magnetic field can be generated and high reliability can be assured. Neighboring memory cells can be disposed at narrower intervals, so that the invention is suitable for realizing higher integration and higher packing density.Type: GrantFiled: July 20, 2004Date of Patent: April 11, 2006Assignee: TDK CorporationInventors: Akifumi Kamijima, Hitoshi Hatate