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

Centre National De La Recherche Scientifique

Commissariat a L'energie Atomique

Université Grenoble Alpes

Aledia

Guy Feuillet

Jesus Zuniga Perez

Philippe Vennegues

Michel El Khoury Maroun

Matthew Charles

Blandine Alloing

Hubert Moriceau

Ivan-Christophe Robin

Hubert Bono

François Templier

Engin Molva

Julien Buckley

Eric Jalaguier

Norbert Moussy

Amélie Dussaigne

Stephane Pocas

Rene Escoffier

Benoit Mathieu

René Escoffier

Stéphane Pocas

Roger Accomo

Stéphanie Gaugiran

Isabelle Bisotto

Claire Bodin-Deshayes

Dang Le Si

Joel Cibert

Roy Dagher

Virginie Brandli

A method for obtaining mesas that are made at least in part of a nitride (N), the method includes providing a stack comprising a substrate and at least the following layers disposed in succession from the substrate a first layer, referred to as the flow layer, and a second, crystalline layer, referred to as the crystalline layer; forming pads by etching the crystalline layer and at least one portion of the flow layer such that: —each pad includes at least: —a first section, referred to as the flow section, formed by at least one portion of the flow layer, and a second, crystalline section, referred to as the crystalline section, framed by the crystalline layer and overlying the flow section, the pads are distributed over the substrate so as to form a plurality of sets of pads; and epitaxially growing a crystallite on at least some of said pads and continuing the epitaxial growth of the crystallites until the crystallites carried by the adjacent pads of the same set coalesce.

Method for producing nitride mesas each intended to form an electronic or optoelectronic device

A process for obtaining a nitride (N) layer preferably obtained from at least one of gallium (Ga), indium (In) and aluminium (Al), may include: on a stack including a substrate and at least the following layers successively disposed from the substrate: a creep layer having a glass transition temperature, T, and a crystalline layer, forming pads by etching the stack so that each pad includes at least a creep segment formed by at least a portion of the creep layer, and a crystalline segment formed by the crystalline layer; and growing by epitaxy a crystallite on each of the pads and continuing the epitaxial growth of the crystallites so as to form the nitride layer. The epitaxial growth may be carried out at a temperature T, such that T≥k1×T, with k1 being 0.8.

Process for obtaining a nitride layer

A method for producing at least one nitride layer includes providing a stack having a plurality of pillars extending from a substrate of the stack. Each pillar includes at least a crystalline section and a summit having a summit surface area The method also includes growing by epitaxy a crystallite from the summit of some the plurality of pillars and continuing the epitaxial growth of the crystallites until the crystallites supported by the pillars coalesce. The plurality of pillars includes at least one retention pillar and separation pillars. The pillars are configured so that once the nitride layer is formed, the at least one retention pillar retains the nitride layer and some of the separation pillars can fracture.

Method for producing a nitride layer

A method for producing an optoelectronic device having nitride-based microLEDs includes providing an assembly having at least one growth substrate and a nitride structure, where the nitride structure has a semipolar nitride layer that includes an active stack and crystallites extending from facets of the growth substrate with a crystalline orientation {111} to the first face of the semipolar nitride layer and providing an integrated control circuit featuring electric connection pads. The assembly is placed on the integrated control circuit, the growth substrate and the crystallites are removed, and trenches are formed in the stack so as to delimit a plurality of islets, each islet being configured to form a microLED.

Method for producing an optoelectronic device comprising microLEDs

A method making it possible to obtain, on an upper surface of a crystalline substrate, a semipolar layer of nitride material comprising any one from among gallium, aluminium or indium, the method comprises the following steps: obtaining, on the upper surface of the crystalline substrate, a plurality of parallel grooves which extend in a first direction, one of the two opposite facets exhibiting a crystal orientation; etching a plurality of parallel slices which extend in a second direction that has undergone a rotation with respect to the first direction of the grooves in such a way as to obtain individual facets exhibiting a crystal orientation; epitaxial growth of the material from the individual facets.

Method making it possible to obtain on a crystalline substrate a semi-polar layer of nitride obtained with at least one of the following materials: gallium (Ga), indium (In) and aluminium (Al)

A method is provided for obtaining a semi-polar nitride layer obtained from a gallium and nitrogen based material on an upper surface of a crystalline substrate of cubic symmetry, including: etching parallel grooves from the upper surface having two opposed inclined facets, one having a crystalline orientation &#x3c;111&#x3e;; forming a mask above the upper surface such that the facets having &#x3c;111&#x3e; orientation are not masked; and then forming the layer by epitaxial growth from the non-masked facets, including: a first epitaxial growth phase to form a seed in parallel grooves; interrupting the first phase when the seed has an inclined facet having a crystalline orientation 0001 and an upper facet having a crystalline semi-polar orientation 101; a surface treatment step including modifying an upper portion of the seed to include silicon; and a second epitaxial growth phase from the inclined facet, continuing until coalescence of seeds of adjacent parallel grooves.

Method of making a semi-polar nitride layer on a crystalline substrate

An optoelectronic device including three-dimensional semiconductor elements predominantly made of a first compound selected from among the group consisting of Compounds III-V, Compounds II-VI, and Compounds IV. Each semiconductor element defines, optionally with insulating portions partially covering said semiconductor element, at least one first surface including contiguous facets angled relative to each other. The optoelectronic device includes quantum dots at least some of the seams between the facets. The quantum dots are predominantly made of a mixture of the first compound and an additional element and are suitable for emitting or receiving a first electromagnetic radiation at a first wavelength.

Optoelectronic device with three-dimensional semiconductor elements

A process allowing at least one semipolar layer of nitride to be obtained, which layer is obtained from a least one among gallium, indium and aluminum on a top surface of a single-crystal layer based on silicon, wherein the process comprises the following steps: etching, from the top surface of the single-crystal layer, a plurality of parallel grooves comprising at least two opposite inclined facets, at least one of two opposite facets having a crystal orientation; masking the top surface of the single-crystal layer such that the facets having a crystal orientation are not masked; and epitaxial growth of the semipolar layer of nitride from the not masked facets; wherein the etching is carried out on a stack comprising the single-crystal layer and at least one stop layer that is surmounted by the single-crystal layer and wherein the etching etches the single-crystal layer selectively with respect to the stop layer so that the etching stops on contact with the stop layer.

Method for obtaining a semi-polar nitride layer on a crystalline substrate

A method for purifying an n-type ZnO and/or ZnMgO substrate to reduce or eliminate the residual extrinsic impurities including introducing a reactive species having strong chemical affinity for at least one of the residual extrinsic impurities, and/or being capable of creating crystalline defects, is introduced in at least one region of the substrate, the reactive species being P, and whereby at least one getter region capable of trapping the said residual extrinsic impurities and/or in which the residual extrinsic impurities are trapped is created in the substrate; then annealing the substrate to cause diffusion of the residual extrinsic impurities towards the getter region and/or to outside the getter region. A method for preparing a p-doped ZnO and/or ZnMgO substrate comprising purifying an n-type ZnO and/or ZnMgO substrate using the above purification method in which one or more reactive species are used not limited to phosphorus alone.

Method for removing residual extrinsic impurities in an N type ZnO or ZnMgO substrate, for P-type doping of this substrate

An assembly method to enable local electrical bonds between zones located on a face of a first substrate and corresponding zones located on a face of a second substrate, the faces being located facing each other, at least one of the substrates having a surface topography. The method forms an intermediate layer including at least one burial layer on the face of the substrate or substrates having a surface topography to make it (them) compatible with molecular bonding of the faces of substrates to each other from a topographic point of view, resistivity and/or thickness of the intermediate layer being chosen to enable the local electrical bonds, brings the two faces into contact, the substrates positioned to create electrical bonds between areas on the first substrate and corresponding areas on the second substrate, and bonds the faces by molecular bonding.

Assembling two substrates by molecular adhesion

A semiconductor heterostructure laser cavity is disclosed which has semiconductor layers epitaxied to define four zones on a substrate. The laser cavity includes a first zone with a composition that varies continuously from a first face to a second face with a gap decreasing from the first face to the second face, the first zone ensuring an optical confinement and light guidance. A second zone constitutes an active emission zone in contact with the second face of the first zone and having at least one quantum well with a gap smaller than that of the first zone. A third zone has a gap larger than that of the at least one quantum well. The third zone ensuring an optical confinement and a light guidance, and having a composition which varies continuously from a first face to a second face with a gap which increases from the first face to the second face, the first face of the third zone being in contact with the active emission zone. A fourth zone constitutes a buffer zone which contacts the second face of the third zone and a substrate, the fourth zone serving as an optical barrier for light guiding, the first and third zones being asymmetrical with respect to the active emission zone to define an asymmetrical GRINSCH structure, one of the first and third zones constituting a surface of the semiconductor heterostructure for ensuring electron excitation and creation of electron-holes.

Asymmetrical semiconductor heterostructure laser cavity and laser

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Saint-Martin d'Uriage, France

Guy Feuillet