Intel Corporation

Stmicroelectronics S.r.l.

Enzo M Donze

Ferdinando Bedeschi

Richard Edward Fackenthal

Meenatchi Jagasivamani

Ravi Annavajjhala

Claudio Resta

Guido Torelli

Ravi Prakash Gutala

Roberto Gastaldi

Salvatore Polizzi

Rich Fackenthal

Anthony Suk Ko

Alessandro Cabrini

Greg Komoto

Meenatchi Jagasivmani

Patrick Wu

A partition may be made up of two planes of memory cells in a phase change memory. These planes may be configured so that they are not adjacent to one another. In some embodiments, this may mean that the adjacent planes may share sensing circuits, reducing the overall size of the memory array. In addition, by using non-adjacent planes to make up a partition, the planes may be spaced in a way which reduces resistance of power conveying lines. This may mean that smaller sized lines may be used, further reducing the size of the overall array.

Interleaved array architecture

The leakage current and power consumption of phase change memories may be reduced using adaptive word line biasing. Depending on the particular voltage applied to the bitline of a programmed cell, the word lines of unselected cells may vary correspondingly. In some embodiments, the word line voltage may be caused to match the bitline voltage of the programmed cell.

Adaptive wordline programming bias of a phase change memory

In a phase change memory, the memory array may be written in relatively small chunks. The writing of data to the array and, particularly, the writing of set data, may be accelerated using a hardware accelerator. The hardware accelerator may include an edge detector which detects a short duration signal pulse to trigger the writing of the set data to a cell. As a result, the writing of data may be accelerated, reducing the time to write in some cases.

Accelerating phase change memory writes

A method for programming multilevel PCM cells envisages: forming an amorphous region of amorphous phase change material in a storage element of a PCM cell by applying one or more reset pulse; and forming a conductive path of crystalline phase change material through the amorphous region by applying one or more set pulse, a size of the conductive path defining a programmed state of the PCM cell and an output electrical quantity associated thereto, and being controlled by the value of the reset pulse and set pulse. The step of forming an amorphous region envisages adaptively and iteratively determining, during the programming operations, a value of the reset pulse optimized for electrical and/or physical properties of the PCM cell, and in particular determining a minimum amplitude value of the reset pulse, which allows programming a desired programmed state and a desired value of the output electrical quantity.

Method for multilevel programming of phase change memory cells using adaptive reset pulses

Program failures during programming can be corrected during reading using an error correcting code. This allows an array to pass programming more readily, speeding the operation of the memory and avoiding the need to continually reprogram or to issue an error message that the programming was unsuccessful. This makes the memory more user friendly and robust.

Programming bit alterable memories

A phase change memory includes a float buffer which stores the result of a comparison between the current state of data in the phase change memory cells and an intended next state of each of those cells. The float buffer indicates which cells need to be programmed in order to achieve the new states and which cells happen to already be in the new states. Then, after programming of the cells, the float buffer indicates which cells still need to be programmed. Thus, a control stage uses the information in the float buffer to program only those cells whose states need to be changed.

Method of storing an indication of whether a memory location in phase change memory needs programming

A memory device including a memory array comprising a set of phase change memory cells configured to store data. The memory device further includes a protection register including a set of protection cells configured to store protection information of the memory cells. The protection cells of the protection register are memory cells of the memory array.

Protection register for a phase-change memory

In a current reference generator device, a voltage reference generator stage generates a reference voltage (V) and an active element output stage receives the reference voltage (V) and outputs a reference current (I) as a function of the reference voltage (V). A control stage is operatively coupled to the voltage reference generator stage and to the active element output stage and controls a first trimmable parameter (m) associated to the voltage reference generator stage and a second trimmable parameter associated to the active element output stage, so as to compensate for changes in a value of the reference current (I) due to manufacturing process deviations.

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Agrate Brianza, Italy

Enzo M Donze