Cypress Semiconductor Corporation

Fujitsu Corporation

Ramtron International Corporation

Infineon Technologies LLC

Fan Chu

Shan Sun

Glen Richard Fox

Alan D DeVilbiss

Brian Lee Eastep

Katsuyoshi Matsuura

Jayant Ashokkumar

Hideyuki Noshiro

Yoshimasa Horii

Takeyasu Saito

Joseph S Tandingan

George Hickert

Jesse J Siman

Xiao-Hong Du

Soichiro Ozawa

Kapil Jain

Bob Sommervold

Edwin Kim

Franklin Brodsky

Craig V Taylor

Ko Nakamura

Jarrod Eliason

Tomohiro Takamatsu

Thomas Davenport

Donald J Verhaeghe

Judith E Allen

Philip Rochette

Qidao Li

Mari Tani

Patrick O'Connell

Lawrence Teresi

Patrick F O'connell

A method of operating a memory device that includes the steps of receiving a read command and a target address in a non-volatile memory (NVM) array, in which the NVM array is divided into a plurality of blocks based on row and column addresses, performing a read operation on NVM cells in the target address and coupling an output of each NVM cell read to a sensing circuit, generating a local reference voltage based on a base reference voltage and an adjustment reference voltage corresponding to the target address of the NVM cells being read and a block that the NVM cells belong thereto, and offsetting the base reference voltage with the adjustment reference voltage, and coupling the local reference voltage to the sensing circuit. Other embodiments are also described.

Local reference voltage generator for non-volatile memory

A memory device including a reference voltage (V) generator and method for operating the same to improve memory sensing margin, and extend operational temperature range and life of the device are disclosed. Generally, the device further includes an array of non-volatile memory cells divided into a plurality of blocks, a sensing circuit coupled to the array to receive and compare memory signals therefrom to the Vto read data from the cells. The Local reference voltage generator is configured to provide one of a number of reference voltages to the sensing circuit based on which of the blocks is being read. The array can be divided based on row and column addresses of cells in the blocks. Where the cells include 1T1C ferroelectric random access memory (F-RAM) cells, and the reference voltages are selected based on a lowest P-term or highest U-term of the cells in the block being read.

A memory device and method of operating the same are disclosed. Generally, the device includes an array of Ferro-electric Random Access Memory cells. Each cell includes a first transistor coupled between a bit-line and a storage node (SN) and controlled by a first wordline (WL), a second transistor coupled between a reference line and the SN and controlled by a second wordline (WL), and a ferro-capacitor coupled between the SN and a plateline. The device further includes a sense-amplifier coupled to the bit-line and reference line, and a processing-element configured to issue control signals to WL, WL, the plateline and the sense-amplifier. The cell is configured and operated to generate a bit-level reference in which a first voltage pulse is applied to the plateline during a read cycle for the data pulse and a second voltage pulse serves as a reference pulse and as a clear pulse.

2T1C ferro-electric random access memory cell

Disclosed herein is an apparatus that includes a ferroelectric capacitor disposed on a damascene barrier film, and fabrication methods thereof. The damascene barrier film includes a hydrogen barrier region and an oxygen barrier region, with the oxygen barrier being in contact with a bottom surface of the ferroelectric capacitor. Other embodiments are also disclosed herein.

Damascene oxygen barrier and hydrogen barrier for ferroelectric random-access memory

An apparatus that includes a reference generating circuit configured to generate a reference signal for a non-volatile memory (NVM) device, the reference generating circuit including a first circuit comprising at least one metal-oxide-semiconductor capacitor, the first circuit generating a first signal component of the reference signal, and a second circuit comprising at least one ferroelectric capacitor, the second circuit generating a second signal component of the reference signal, in which the second signal component is temperature dependent.

Hybrid reference generation for ferroelectric random access memory

A memory device and array which includes a static random access memory (SRAM) circuit coupled to a non-volatile circuit, such as a ferroelectric-RAM (F-RAM) circuit, in which the F-RAM circuit stores a bit of data from the SRAM circuit during power-out periods, the F-RAM circuit is further coupled to bit-line(s) to output the bit of data stored in the F-RAM circuit when operation power is restored.

Non-volatile static RAM and method of operation thereof

A device including a ferroelectric memory and methods of manufacturing the same are provided. In one embodiment, the device includes a semiconductor die with an integrated circuit fabricated thereon, a stress buffer die mounted to the semiconductor die overlying the integrated circuit, and a molding compound encapsulating the semiconductor die and the stress buffer die. Generally the integrated circuit includes a ferroelectric memory. In some embodiments, the device further includes a polyimide layer between the stress buffer and the semiconductor die. Other embodiments are also provided.

Ferroelectric memories with a stress buffer

An array of ferroelectric memory cells that allows imprint mitigation includes ferroelectric memory cells respectively coupled to word lines, plate lines, and bit lines; a word line driver for driving the word lines; a plate line driver for driving the plate lines; a bit line driver for driving the bit lines; and an isolation device driver for driving isolation devices coupled between the bit lines and a plurality of bit lines. The method for mitigating imprint includes coupling the bit lines to a respective plurality of sense amplifiers, turning on a word line and pulsing a plate line associated with a row of ferroelectric memory cells, disconnecting the bit lines from the respective sense amplifiers, driving the plate line low and the bit lines high, driving the plate line high and the bit lines low, driving the plate line low and floating the bit lines, driving the bit lines with the sense amplifier, and turning off the word line and precharging the bit lines. The method can be performed after each memory access, or can be performed whenever convenient with a counter and a rejuvenate command.

Method for mitigating imprint in a ferroelectric memory

A ferroelectric reference circuit generates a reference voltage proportional to (P+U)/2 and is automatically centered between the bit line voltages corresponding to the P term and the U term across wide temperature and voltage ranges. To avoid fatiguing the reference ferroelectric capacitors generating (P+U)/2, the reference voltage is refreshed once every millisecond. To eliminate the variation of the reference voltage due to the leakage in the ferroelectric capacitors during this period of time, the reference voltage generated from the reference ferroelectric capacitors is digitized when it is refreshed. The digital value is fixed and converted to an analog value which is then fed into sense amplifiers for resolving the data states. The reference voltage is automatically at the center of the switching (P) and non-switching (U) signals and therefore the signal margin is maximized.

Circuit for generating a centered reference voltage for a 1T/1C ferroelectric memory

A method of fabricating a semiconductor device having a ferroelectric capacitor includes the steps of forming a lower electrode layer of the ferroelectric capacitor on an insulation film covering an active device element, forming a ferroelectric film on the lower electrode layer as a capacitor insulation film, crystallizing the ferroelectric film by applying a thermal annealing process in an atmosphere containing a non-oxidizing gas and an oxidizing gas, and forming an upper electrode layer on the ferroelectric film.

Semiconductor device having a ferroelectric capacitor and a fabrication process thereof

A method for fabrication of ferroelectric capacitor elements of an integrated circuit includes steps of deposition of an electrically conductive bottom electrode layer, preferably made of a noble metal. The bottom electrode is covered with a layer of ferroelectric dielectric material. The ferroelectric dielectric is annealed with a first anneal prior to depositing a second electrode layer comprising a noble metal oxide. Deposition of the electrically conductive top electrode layer is followed by annealing the layer of ferroelectric dielectric material and the top electrode layer with a second anneal. The first and the second anneal are performed by rapid thermal annealing.

Process for producing high quality PZT films for ferroelectric memory integrated circuits

A ferroelectric random access memory has a ferroelectric capacitor formed of a stacking of a lower electrode, a PZT film and an upper electrode of SrRuO , wherein the PZT film includes pinholes, with a pinhole density of about 17 &mgr;m or less.

Ferroelectric semiconductor memory device and a fabrication process thereof

A ferroelectric thin film capacitor and a method for producing the same wherein the capacitor dielectric includes multi-layered crystallographic textures. An integrated circuit device, such as a non-volatile memory device, includes at least one capacitor having a top and bottom electrode thereof and a ferroelectric dielectric layer therebetween. The ferroelectric dielectric layer comprises a first ferroelectric layer having a first crystallographic texture forming a main body of the dielectric layer and a second ferroelectric layer having a second differing crystallographic texture forming an interface layer between the main body and one of the top and bottom electrodes.

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Colorado Springs, CO, United States of America

Fan Chu