Commissariat &#xc0; L'&#xc9;nergie Atomique Et Aux &#xc9;nergies Alternatives

Centre National De La Recherche Scientifique

Renault S.a.s.

Commissariat a L'energie Atomique

Commissariat À I'energie Atomique

Bertrand Delaet

Marie-Claire Cyrille

Sophie Giroud

Dimitri Houssameddine

Ursula Ebels

Rachid Hida

Sylvain Bacquet

Ivan-Christophe Robin

Bernard Viala

Guillaume Jourdan

Stéphane Caplet

Loic Joet

Jean-François Nodin

Veronique Sousa

Jean-Francois Nodin

Véronique Sousa

Mathilde Cartier

Frédéric Auzas

Marie Claire Cyrille

Marie- Claire Cyrille

A method of manufacturing an electronic device, including: a) forming a plurality of chips, each including a plurality of connection areas and at least one first pad; b) forming a transfer substrate including, for each chip, a plurality of connection areas and at least one second pad, one of the first and second pads being a permanent magnet and the other one of the first and second pads being either a permanent magnet or made of a ferromagnetic material; and c) affixing the chips to the transfer substrate to connect the connection areas of the chips to the connection areas of the transfer substrate, by using the magnetic force between the pads to align the connection areas of the chips with the corresponding connection areas of the transfer substrate.

Process for manufacturing an LED-based emissive display device

A permanent magnet comprising an antiferromagnetic layer and a ferromagnetic layer having a first sub-layer made of a first type of ferromagnetic material, the first type of ferromagnetic material being an at least partially crystallized alloy of iron and cobalt, and a second sub-layer made of a second type of ferromagnetic material, this second type of ferromagnetic material also being an alloy of iron and cobalt in which the proportion of face-centered cubic crystals is less than the proportion of face-centered cubic crystals in the first type of ferromagnetic material.

Permanent magnet comprising an antiferromagnetic layer and a ferromagnetic layer

A magnetic field gradient sensor includes a support and a structure having at least a first and a second mobile element, at least one magnetic sensor, each magnetic sensor being mechanically secured to one of the first and/or second mobile elements so as to be able to apply a mechanical force to the structure in the presence of a magnetic field gradient, a coupler for coupling between the first and second mobile elements so that the structure can be moved in at least one balanced mechanical mode in the presence of a magnetic field gradient, and a sensor for measuring the movement of the structure at least in balanced mode.

Magnetic field gradient sensor with reduced sensitivity to vibrations

A permanent magnet including, at least once per group of ten consecutive ferromagnetic layers, a growth layer directly interposed between a top antiferromagnetic layer of a previous pattern and a bottom antiferromagnetic layer of a following pattern. This growth layer is entirely realized in a nonmagnetic material chosen from the group made up of the following metals: Ta, Cu, Ru, V, Mo, Hf, Mg, NiCr and NiFeCr, or it is realized by a stack of several sublayers of nonmagnetic material disposed immediately on one another, at least one of these sublayers being entirely realized in a material chosen from the group. The thickness of the growth layer is greater than 0.5 nm.

Permanent magnet comprising a stack of N patterns

A permanent magnet includes a stack of N patterns stacked immediately one above the other in a stacking direction, each pattern including an antiferromagnetic layer made of antiferromagnetic material, a ferromagnetic layer made of ferromagnetic material, the directions of magnetization of the various ferromagnetic layers of all the patterns all being identical to one another. At least one ferromagnetic layer includes a first sub-layer made of CoFeB whose thickness is greater than 0.05 nm, and a second sub-layer made of a ferromagnetic material different from CoFeB and whose thickness is greater than the thickness of the first sub-layer.

A permanent magnet includes at least two antiferromagnetic layers and at least two first ferromagnetic layers. A magnetization direction of each first ferromagnetic layer is set, by an exchange coupling, with one of the antiferromagnetic layers of the stack, parallel to and in the same direction as the magnetization directions of the other first ferromagnetic layers. The permanent magnet also includes at least one second ferromagnetic layer. A magnetization direction of each second ferromagnetic layer is pinned only by RKKY (Ruderman-Kittel-Kasuya-Yosida) coupling with at least one of the first ferromagnetic layers or with at least one other of the second ferromagnetic layers.

Permanent magnet comprising a stack of ferromagnetic and antiferromagnetic layers

A sensor of magnetic fields along a direction of measurement comprising N magneto-resistive transducers TM, a resistance of each transducer TMvarying linearly to within &#xb1;x% as a function of an intensity of a magnetic field to be measured within a maximum range [a; b] of intensity of the magnetic field to be measured and non-linearly outside of this range, the index i being an identifier of the transducer TM. The sensor further comprises a generator which generates N magnetic fields CMusing at least one permanent magnet, where each magnetic field CMexhibits an intensity Iin the direction of measurement. The intensity Ibeing constant and independent of the intensity of the magnetic field to be measured and each transducer TMbeing placed inside a respective magnetic field CM. Each transducer TMplaced inside the magnetic field CMforming a measurement block for which the range in which the resistance of the transducer TMof said block varies linearly to within &#xb1;x% is offset by Iand becomes [a+I; b+I]. Each intensity Ibeing different from the others so as to obtain N different ranges [a+I; b+I], being an integer number greater than or equal to two. There is further included a computer capable of selecting one or more measurement blocks for which the intensity of the magnetic field to be measured lies within the range [a+I; b+I] of the block, and establishing the measurement of the intensity of the magnetic field on the basis of the measurement of only the one or more measurement blocks selected.

Magnetic field sensor

A method for measuring a first magnetic field and the temperature of a magneto-resistive transducer includes producing, by the magneto-resistive transducer, a measurement signal dependent on the intensity of the first magnetic field and on the temperature of the magneto-resistive transducer. The method includes establishing a measurement of the intensity of the first magnetic field on the basis of the measurement signal produced and a measurement of the temperature of the magneto-resistive transducer. The method also includes generating a second magnetic field to combine with the first magnetic field to form a resultant magnetic field. The method further includes extracting from the measurement signal, the component which is dependent solely on the second magnetic field and establishing the temperature of the magneto-resistive transducer on the basis of the component extracted.

Method and device for measuring a magnetic field and the temperature of a magneto-resistive transducer

A magnetic field sensor has a magnetoresistive rod having a stack of stacked layers that include a pinned layer having a fixed magnetization direction almost perpendicular to a longitudinal direction, a free layer comprising a magnetostrictive material having a coefficient of magnetostriction greater than 20 ppm to 25&#xb0; C. and a longitudinal axis of easiest magnetization, the magnetization changing when the free layer is exposed to a magnetic field, a non-magnetic spacer layer interposed between the free and pinned layers to form a tunnel junction or spin valve, and a stress-generating layer for exerting uniaxial stress essentially such that a product of stress and magnetostriction coefficient is greater than 500 ppm&#xb7;MPa at 25&#xb0; C. The rod's length is at least ten times its greatest width.

The invention relates to a radiofrequency oscillator which incorporates: a spin-polarized electric current magnetoresistive device (), a terminal () for controlling the frequency or amplitude of the oscillating signal, a servo loop () connected between the output terminal and the control terminal for applying a control signal to the control terminal in order to slave a characteristic of the oscillating signal to a reference value, the servo loop () comprising: a sensor () of the amplitude of the oscillating signal oscillations, and a comparator () capable of generating the control signal according to the measured amplitude and the reference value.

Magnetoresistive radiofrequency oscillator and method for generating an oscillating signal

The invention relates to a radiofrequency oscillator which incorporates: a spin-polarized electric current magnetoresistive device () for generating an oscillating signal at an oscillation frequency on an output terminal (), and a terminal () for controlling the frequency or amplitude of the oscillating signal, and a feedback loop () comprising an amplifier () provided with: an input connected to the output terminal () of the magnetoresistive device () so as to amplify the portion of an oscillating signal detected at the output terminal, and an output connected to the control terminal () so as to inject onto said control terminal the amplified portion of the oscillating signal which is phase-related to the oscillating signal generated at the output terminal.

A radiofrequency oscillator comprises: a free layer (), a current injector () for injecting spin-polarized current into the free layer, this injector having a spin-polarized current injection face () directly in contact with the free layer, a magnetoresistive contact () having a measurement face () directly in contact with the free layer, in order to form, in combination with the free layer, a tunnel junction for measuring the precession of the magnetization of the free layer, a conducting pad () directly in contact with the free layer in order to make an electrical current flow through the injector without passing through the magnetoresistive contact. At least part of the measurement face () and part of the injection face () are placed facing each other on each side of the free layer ().

Magnetoresistive radiofrequency oscillator

This magnetic device integrates a magneto-resistive stack, the stack comprising at least two layers made out of a ferromagnetic material, separated from each other by a layer of non-magnetic material; and means for causing an electron current to flow perpendicular to the plane of the layers, with at least one integrated nano-contact intended to inject the current into the magneto-resistive stack. The nano-contact is made in a bilayer composed of a solid electrolyte on which has been deposited a soluble electrode composed of a metal that has been at least partially dissolved in the electrolyte.

Magnetic device with integrated magneto-resistive stack

This radio-frequency oscillator includes a magnetoresistive device in which an electric current is able to flow. The magnetoresistive device includes a first magnetic layer, known as a 'trapped layer', whereof the magnetization is of fixed direction. The magnetoresistive device further includes a second magnetic layer known as a 'free layer' and a non-magnetic layer, known as an &#x201c;intermediate layer&#x201d;, interposed between the first and second layer, known as the intermediate layer. The oscillator further includes means capable of causing an electron current to flow in said layers constituting the aforementioned stack and in a direction perpendicular to the plane which contains said layers. One of the three layers constituting the magnetoresistive device includes at least one constriction zone of the electric current passing through it.

Growing community of inventors

Bernin, France

Bertrand Delaet