EP1829099A1 - Method for treating the surface of a wafer - Google Patents

Method for treating the surface of a wafer

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Publication number
EP1829099A1
EP1829099A1 EP05823924A EP05823924A EP1829099A1 EP 1829099 A1 EP1829099 A1 EP 1829099A1 EP 05823924 A EP05823924 A EP 05823924A EP 05823924 A EP05823924 A EP 05823924A EP 1829099 A1 EP1829099 A1 EP 1829099A1
Authority
EP
European Patent Office
Prior art keywords
bonding
wafer
donor
cleaning
solution
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP05823924A
Other languages
German (de)
French (fr)
Inventor
Christophe Maleville
Daniel Delprat
Cécile DELATTRE
Frédéric Metral
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Soitec SA
Original Assignee
Soitec SA
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from FR0413922A external-priority patent/FR2880185B1/en
Priority claimed from FR0413930A external-priority patent/FR2880186B1/en
Application filed by Soitec SA filed Critical Soitec SA
Publication of EP1829099A1 publication Critical patent/EP1829099A1/en
Withdrawn legal-status Critical Current

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Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/70—Manufacture or treatment of devices consisting of a plurality of solid state components formed in or on a common substrate or of parts thereof; Manufacture of integrated circuit devices or of parts thereof
    • H01L21/71—Manufacture of specific parts of devices defined in group H01L21/70
    • H01L21/76—Making of isolation regions between components
    • H01L21/762—Dielectric regions, e.g. EPIC dielectric isolation, LOCOS; Trench refilling techniques, SOI technology, use of channel stoppers
    • H01L21/7624—Dielectric regions, e.g. EPIC dielectric isolation, LOCOS; Trench refilling techniques, SOI technology, use of channel stoppers using semiconductor on insulator [SOI] technology
    • H01L21/76251—Dielectric regions, e.g. EPIC dielectric isolation, LOCOS; Trench refilling techniques, SOI technology, use of channel stoppers using semiconductor on insulator [SOI] technology using bonding techniques
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer
    • H01L21/18—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic Table or AIIIBV compounds with or without impurities, e.g. doping materials
    • H01L21/30—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26
    • H01L21/302—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26 to change their surface-physical characteristics or shape, e.g. etching, polishing, cutting
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer
    • H01L21/18—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic Table or AIIIBV compounds with or without impurities, e.g. doping materials
    • H01L21/20—Deposition of semiconductor materials on a substrate, e.g. epitaxial growth solid phase epitaxy

Definitions

  • the present invention relates to the bonding of two wafers comprising semiconductor materials, in order to produce structures that can be used in the fields of microelectronics, optics or optoelectronics.
  • the invention relates more specifically to the activation of the bonding surface of at least one of the two wafers to be bonded, and this, while this latter has optionally been oxidized and / or has undergone implantation of atomic species. .
  • Such an implantation of atomic species makes it possible to form an embrittlement zone, within a so-called "donor" wafer, at a determined depth.
  • the quality of the bonding is essential to achieve a good layer transfer, the quality of this bonding being mainly measured by the bonding energy bonding the two wafers.
  • the implantation step generally brings hydrocarbon-type contaminants to the platelet surface. In the presence of isolated particles or localized surface defects, this contamination can lead to the formation of superficial blisters, after detachment of the thin film and its transfer to the receptor plate, or even to the formation of non-transferred zones.
  • substrates of the SOI type in which the buried oxide layer is very thin, that is to say less than 50 nm (50 nanometers) are more difficult to produce because much more sensitive to the appearance of defects of the "blistering" type. It is therefore also important to reinforce the bonding energy to extend the conditions of use and the application possibilities of the aforementioned "Smart Cut TM” method.
  • the bonding energy must also be reinforced, in order to favor a detachment and a correct layer transfer. Indeed, the existence of contaminants at the bonding interface can lead to a detachment of the layer, at this interface, and not at the weakening zone, thereby creating defects (areas not transferred) on the receptor plate, which correspond to residues on the donor wafer. The lower the bonding energy, the greater the amount of non-transferred areas.
  • the bonding wave has more difficulties to reach the edge of the wafer diametrically opposite to that where the bonding was initiated and there is a greater number defects in this region.
  • several surface treatment processes are known beforehand in the state of the art, before bonding.
  • cleaning before bonding a second cleaning step, carried out immediately before bonding and hereinafter referred to as "cleaning before bonding".
  • the cleaning step a) surfaces to be bonded aims to: - make these surfaces hydrophilic
  • RCA cleaning and activation process
  • SCl a first bath of a solution known by the acronym "SCl” (according to the English terminology of "Standard Clean 1” which means “standard cleaning solution 1”), and which comprises a mixture of hydroxide ammonium (NH 4 OH), hydrogen peroxide (H2O2) and deionized water, - a second bath of a solution known by the acronym "SC2"
  • Standard Clean 2 which means “standard cleaning solution 2”
  • standard cleaning solution 2 which comprises a mixture of hydrochloric acid (HCl), hydrogen peroxide (H2O2) and deionized water.
  • the first bath is intended primarily to remove the isolated particles present on the surface of the wafer and make the surfaces hydrophilic, while the second bath is rather intended to remove metal contamination.
  • WO-2005/096369 a method of cleaning the oxidized surface of a wafer, for its bonding to another wafer.
  • Such a process uses a mixture of ammonia (NH 4 OH) and hydrogen peroxide (H2O2) and allows to remove the isolated particles, while avoiding creating a surface roughness.
  • step b) cleaning before bonding is very specific, since it conditions the quality of the substrates obtained after the layer transfer step (s).
  • This step is intended to remove the particles that may have settled during the waiting time between the cleaning step a) and the bonding. It also aims to enhance the hydrophilicity of the pads, the latter having a tendency to significantly decrease the waiting time between the cleaning step a) and the bonding is long.
  • This cleaning step b) is generally carried out by brushing the surfaces to be bonded with a deionized water solution, see for example on this subject the patent application FR 2 854 493.
  • the present invention aims to overcome the aforementioned drawbacks and to introduce a chemical activation of the surfaces, during the cleaning step before bonding, preferably carried out at room temperature, in order to simplify the preliminary step a) cleaning, or even to remove it.
  • the invention also aims, if the preliminary cleaning step a) is maintained, to increase the duration of the storage and activation time platelets between this cleaning step a) and the cleaning step before bonding according to the invention, while maintaining a high bonding energy, after the bonding of the two wafers.
  • the activation step according to the invention must also be integrated in the best industrial process for manufacturing SOI type substrates, already existing.
  • the invention relates to a method of treating one or the other or both surfaces, called “gluing” a first wafer, called “donor” and a second wafer, called “ receiver “, intended to be glued against each other, for the purpose of manufacturing a structure used in the field of optics, electronics or optoelectronics.
  • this process comprises a cleaning and activation step, carried out immediately before the gluing of said donor and receiver platelets, by application to said one or more bonding surfaces of a so-called "surface treatment” solution.
  • a so-called "surface treatment” solution comprising at least about 97% of a solution of ammonia (NH 4 OH) in water, preferably deionized, in a mass concentration of between about 0.05% and 2%.
  • the treatment solution consists of a solution of ammonia (NH 4 OH) in water, preferably deionized, in a mass concentration of between about 0.05% and 2%;
  • the treatment solution consists of approximately 97% of a solution (NH 4 OH) in water, preferably deionized, in a mass concentration of between approximately 0.05% and 2% and approximately 3% by weight.
  • a solution NH 4 OH
  • chelating agents and / or surfactants e.g., sodium EDTA, sodium EDTA, sodium metabisulfite, sodium metabisulfite, sodium metabisulfite, sodium metabisulfite, sodium metabisulfite, sodium metabisulfite, sodium metabisulfite, sodium metabisulfite, sodium metabisulfite, sodium metabisulfite, sodium metabisulfite, sodium metabisulfite, sodium metabisulfite, sodium metabisulfite, sodium metabisulfite, sodium metabisulfite, sodium metabisulfite, sodium metabisulfite, sodium metabisulfite, sodium metabisulfite, sodium metabisulfite, sodium metabisulfite, sodium metabisulfite, sodium metabisul
  • the ammonia solution (NH 4 OH) has a mass concentration in water of between approximately 0.5% and 1.6%, more preferably around 0.8%;
  • the cleaning and activation step is carried out by applying said surface treatment solution at a temperature less than or equal to
  • the surface treatment solution is applied directly to the gluing machine, preferably for a period of between 10 seconds and 2 minutes;
  • Said cleaning and activation step is performed by performing simultaneously the application of said surface treatment solution and the brushing of the bonding surface to be treated;
  • At least one of the two bonding surfaces is covered with an oxide layer
  • the donor wafer has undergone implantation of atomic species before bonding, so as to form a weakening zone, delimiting a thin layer to be transferred.
  • the invention also relates to a method of manufacturing a structure intended to be used in the field of optics, electronics or optoelectronics.
  • this method comprises the following steps:
  • This method comprises a consolidation annealing step between the bonding step and the detaching step;
  • the donor wafer is made of a semiconductor material, silicon or constrained silicon. This method makes it possible in particular to manufacture a structure of the semiconductor on insulator or silicon on insulator (SOI) type.
  • FIGS. 1a to 1d represent the main steps of a method for sampling and transfer of layers, applied to the production of an SOI type substrate;
  • FIG. 2 is a diagram representing a technique for measuring energy gluing between two platelets,
  • FIG. 3 is a graph representing the bonding energy ⁇ between two wafers, as a function of the temperature of the annealing treatment, for platelet series having respectively undergone either a "control" cleaning and activation method, or the cleaning and activation process before bonding according to the invention,
  • FIG. 4 is a graph illustrating the results of the measurement of the number of transfer defects in a reported layer, from series of platelets having respectively undergone either a "control" cleaning and activation method, or the method of cleaning and activation before bonding according to the invention
  • FIG. 5 shows the evolution of the value of the bonding energy ⁇ between two platelets, for batches of platelets having undergone a first cleaning treatment, then a second cleaning and activation treatment immediately before bonding, but shifted in time compared with the first cleaning, this second treatment being either a "control" cleaning or a treatment according to the invention.
  • a main objective of the present invention is to reduce the importance of defects and surface roughness, of at least one of two plates to be glued against each other, in order to increase the energy bonding between these pads.
  • the invention applies more particularly to platelets covered with an oxide layer, this oxide being either "native", that is to say resulting from the oxidation in the open air of the wafer, or additional and resulting from a thermal treatment of this wafer or deposition of an oxide layer, for example.
  • the invention finds particular application in the implementation of a method of manufacturing an SOI type substrate.
  • a first step consists in oxidizing a wafer made of semiconductor material 13, so as to form a donor wafer 10 having on the surface an oxide layer 11.
  • this oxidation results from a heat treatment or the deposition of an oxide layer, for example an SiO 2 layer when the wafer 13 is made of silicon.
  • the donor wafer 10 is subjected, through one of its oxidized surfaces, to an implantation of atomic species (s), such as an implantation of hydrogen and / or helium, for example.
  • atomic species such as an implantation of hydrogen and / or helium, for example.
  • the energy and the doses of this implantation are chosen so as to form an embrittlement zone 15, at a determined depth below the surface of the donor wafer 10, more precisely inside the wafer 13. thin 16, delimited on the one hand by the weakening zone 15 and on the other hand by the oxide layer 11.
  • the oxidized surface of the donor wafer 10, which has been implanted, is designated by the reference numeral 12.
  • the surfaces 12 and 22, which are bonded by molecular adhesion, are then brought into contact with each other.
  • an annealing step is optionally implemented to reinforce the bonding interface 17 between the donor and recipient platelets 20.
  • an energy of thermal, mechanical and / or chemical origin sufficient to carry out the detachment along the embrittlement zone 15 and thereby detach the thin layer 16, from the rest 18 of the donor plaque.
  • the semiconductor-on-insulator structure shown in FIG. 1D is thus obtained, the thin layer 16 taken from the donor wafer 10 forming the semiconductor portion and the underlying oxide layer 11 forming the electrically insulating portion.
  • This structure is referenced 30.
  • a finishing step, using, for example, a chemical-mechanical polishing, is then optionally implemented to make up for any defects or roughness occurring during the detachment of the thin layer 16.
  • the final structure 30 thus obtained is intended for applications in the field of microelectronics, optics or optoelectronics.
  • the receptor plate 20 could possibly be covered with a layer of oxide, in particular native oxide.
  • the object of the invention is to provide a method of cleaning and activation, surfaces to be bonded, that is to say in the above example, surfaces 12 and / or 22. This method not only allows to remove contaminants or isolated particles, but also to activate surfaces to stick.
  • the applicant has observed that the treatment of the bonding surfaces of two wafers to be bonded, or at least one of these surfaces, with the aid of a specific solution made it possible to increase the bonding energy between these two wafers.
  • this solution is called "surface treatment”.
  • This surface treatment solution comprises at least about 97% of a solution of ammonia (NH 4 OH) in water, preferably deionized, in a mass concentration of between about 0.05% and 2%.
  • the surface treatment solution consists of a solution of ammonia (NH 4 OH) in water, preferably deionized, in a mass concentration of between about 0, 05% and 2%,
  • This solution of ammonia is a pure solution, that is to say a solution whose concentration of pollutant type metallic contaminants (copper, iron, chromium, titanium, nickel, aluminum) and / or alkaline contaminants, (lithium, sodium, calcium, potassium, etc.) do not exceed a concentration of 10 ppt (part per trillion) for each element.
  • a surface treatment solution consisting of approximately 97% of the abovementioned ammonia solution and approximately 3% of chelating agents and / or surfactants is used.
  • chelating agents indeed make it possible to fix the contaminants, such as metals or ions in solution, which are often present in the commercially available ammonia and which might remain trapped at the bonding interface, thereby modifying the electrical characteristics of the final substrate obtained.
  • the surfactant makes it possible to increase the efficiency of removal of particles that can lead to the formation of superficial blisters.
  • the mass concentration of the ammonia solution is between 0.5% and 1.6%, or better still close to 0.8%.
  • the ammonia solution mentioned above is used at room temperature. It can, however, be applied at higher temperatures but preferably not exceeding 70 ° C. Indeed, at higher temperatures, the roughness of the surfaces increases sharply, which leads to an increase in the number of defects of the "blister" type.
  • the aforementioned cleaning and activation treatment is carried out immediately before gluing, preferably directly on the gluing machine, in order to reactivate the hydrophilicity of the wafers put in contact, even if they have been waiting for several hours after the cleaning step, as will be detailed later.
  • the activating solution can be distributed, either directly on the wafers to be treated without brushing, or directly on the brushes used for activation or on the wafers, before a subsequent brushing.
  • the ammonia solution is preferably delivered for a period of 10 seconds to 2 minutes, preferably 30 seconds to 1 minute, at a flow rate of the order of 1.5 1 / min and directly at the gluing equipment, for example using a distributor arm.
  • the ammoniacal solution may be dispensed from specific cleaning equipment, for example by spraying (equipment of the "single wafer” type) or of the bath type (equipment of the "wet bench” type).
  • the Applicant has carried out a comparative study of the bonding energy at the interface between two wafers, with series of wafers having respectively undergone either a so-called "control" cleaning and activation process, or the method according to US Pat. the invention.
  • the Applicant has inserted a blade 40 on one or more edges of the set of plates 10 and 20 in contact with each other, at the interface of FIG. collage 17.
  • the length L between the outer edge of the plates 10, 20 and the stopping point of the detachment, which corresponds to the sum of the length of the area locally peeled off by the blade 40 and the length of the propagation of the separation zone gives an indication of the bonding energy that exists between the two wafers 10 and 20.
  • the end of the separation corresponds to a balance between the bonding energy and the elastic deformation characterizing the detachment.
  • FIG. 3 represents the bonding energy ⁇ , as a function of the temperature of a possible annealing treatment (called “consolidation treatment”), carried out for 2 hours. Some of the structures did not undergo this subsequent consolidation treatment (results obtained when the temperature is close to 20 ° C), and others have undergone this treatment for 2 hours, at various temperatures.
  • control treatment The dotted line curve represents the results obtained with the batches, in which the platelet bonding surfaces have undergone a water rinsing treatment and simultaneous brushing activation, this treatment being carried out immediately before bonding. This treatment is hereinafter referred to as "control" treatment.
  • the solid line represents the results obtained with the batches, in which the platelet bonding surfaces have undergone the cleaning and activation treatment in accordance with the invention.
  • the ordinate axis represents the number of transfer defects N measured, per plate.
  • the abscissa axis represents the results obtained, on the one hand with the control batches Te, for which the surface treatment step was carried out according to the "control" method mentioned above, and on the other hand, with the batches I , in which the cleaning and activation step has been carried out in accordance with the invention, as described with reference to FIG.
  • the average number of transfer defects N in the first case is 4.09, while it is close to 0.83 in the second case.
  • Both wafers were silicon and measured eight inches in diameter (200 mm).
  • the first cleaning treatment was of the aforementioned RCA type.
  • the cleaning and activation treatment according to the invention was carried out by brushing, under a dilute ammonia solution, at a mass concentration of less than 0.5%, in deionized water.
  • the solid line represents the results obtained with platelets having undergone the "control" surface treatment described in conjunction with FIGS. 3 and 4.
  • the dotted line represents the results obtained with platelets having undergone the cleaning and activation treatment according to the invention.
  • the applicant has highlighted the interest of implementing the cleaning and activation method according to the invention, in a method of sampling and transfer of layer, and more specifically in the manufacture of an SOI type substrate.
  • the method according to the invention makes it possible to increase the bonding energy, which makes it possible to be less demanding concerning the criteria for carrying out a first cleaning carried out a certain time before bonding, or even to completely eliminate it. this.
  • the activation method according to the invention makes it possible to reduce the number of edge plate transfer defects to less than one per plate on average, thereby considerably increasing the quality of the thin layer. in which the future electronic components will be made.
  • the present invention is not limited to an activation method for bonding two silicon wafers, at least one of which is coated with a silicon oxide layer, but can be extended to any type of material, such as constrained silicon or other semiconductor material that can be used in Smart Cut TM technology.

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • General Physics & Mathematics (AREA)
  • Manufacturing & Machinery (AREA)
  • Computer Hardware Design (AREA)
  • Microelectronics & Electronic Packaging (AREA)
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  • Cleaning Or Drying Semiconductors (AREA)
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Abstract

The invention concerns a method for treating either surface or both surfaces (12, 22), called bonding surfaces of a first so-called donor wafer (10) and of a second so-called receiver wafer (20), designed to be bonded together. The method is characterized in that it comprises a step of cleaning and activating, performed immediately prior to the bonding of said donor (10) and receiver (20) wafers, by applying on said bonding surface(s) (12, 22) a so-called treating solution, comprising at least 97 % of an ammonia solution (NH<SUB>4</SUB>OH) in water, preferably deionized, in a mass concentration ranging between about 0.05 % and 2 %. The invention is useful for making structures used in the field of optics, electronics or optoelectronics.

Description

Procédé de traitement d'une surface de plaquette. Method of treating a wafer surface
La présente invention concerne le collage de deux plaquettes comprenant des matériaux semi-conducteurs, afin de réaliser des structures utilisables dans les domaines de la microélectronique, l'optique ou l'optoélectronique. L'invention concerne plus précisément l'activation de la surface de collage d'au moins l'une des deux plaquettes à coller, et ce, alors que celle-ci a éventuellement été oxydée et/ou a subi une implantation d'espèces atomiques.The present invention relates to the bonding of two wafers comprising semiconductor materials, in order to produce structures that can be used in the fields of microelectronics, optics or optoelectronics. The invention relates more specifically to the activation of the bonding surface of at least one of the two wafers to be bonded, and this, while this latter has optionally been oxidized and / or has undergone implantation of atomic species. .
Une telle implantation d'espèces atomiques permet de former une zone de fragilisation, à l'intérieur d'une plaquette, dite "donneuse", à une profondeur déterminée.Such an implantation of atomic species makes it possible to form an embrittlement zone, within a so-called "donor" wafer, at a determined depth.
Ce procédé connu sous la dénomination « Smart Cut ™ » (marque déposée) est connu de l'homme du métier. On pourra par exemple se référer à l'ouvrage "Silicon-on-Insulator Technology, Materials to VLSI, 2èroe édition, deThis process known under the name "Smart Cut ™" (registered trademark) is known to those skilled in the art. May for example refer to the book "Silicon-on-Insulator Technology, Materials to VLSI, 2 eroe publishing,
Jean-Pierre Colinge, édité par Kluwer Académie Publishers, pages 50 et 51). On peut ainsi réaliser une structure connue sous l'acronyme "SOI",Jean-Pierre Colinge, edited by Kluwer Academy Publishers, pages 50 and 51). It is thus possible to produce a structure known under the acronym "SOI",
(d'après la terminologie anglo-saxonne "Silicon On Insulator"), en réalisant une implantation à travers la surface oxydée d'une plaquette donneuse en silicium et en reportant par collage, sur une plaquette de silicium, dite "réceptrice", un film mince incluant la couche d'oxyde superficielle et la couche mince supérieure de silicium, issues de ladite plaquette donneuse.(By the English terminology "Silicon On Insulator"), by performing an implantation through the oxidized surface of a silicon donor wafer and by gluing, on a silicon wafer, called "receiver", a thin film including the surface oxide layer and the upper silicon thin layer from said donor wafer.
La miniaturisation de plus en plus importante des composants électroniques, qui sont formés sur les couches minces ainsi reportées, impose aux fabricants de substrats, de réaliser des substrats de type SOI, dans lesquels la couche supérieure de silicium est de plus en plus mince, tout en étant d'excellente qualité. En conséquence, il est impératif d'améliorer la qualité des couches reportées et donc d'améliorer les techniques de prélèvement et de report de telles couches.The increasing miniaturization of electronic components, which are formed on the thin films thus reported, requires substrate manufacturers to make SOI-type substrates, in which the upper layer of silicon is becoming thinner, while being of excellent quality. Consequently, it is imperative to improve the quality of the layers reported and thus to improve the techniques of sampling and carrying such layers.
La qualité du collage est essentielle pour réaliser un bon report de couche, la qualité de ce collage étant principalement mesurée par l'énergie de collage liant les deux plaquettes.The quality of the bonding is essential to achieve a good layer transfer, the quality of this bonding being mainly measured by the bonding energy bonding the two wafers.
Or, on a pu constater, comme expliqué ci -après, que l'existence de certains contaminants, à la surface des plaquettes, avait pour effet de diminuer l'énergie de collage. L'étape d'implantation amène généralement des contaminants de type hydrocarbures à la surface des plaquettes. En présence de particules isolées ou de défauts de surface localisés, cette contamination peut conduire à la formation de cloques superficielles, après le détachement du film mince et son report sur la plaquette réceptrice, voire même à la formation de zones non transférées.However, it has been found, as explained below, that the existence of certain contaminants on the surface of the wafers, had the effect of reducing the bonding energy. The implantation step generally brings hydrocarbon-type contaminants to the platelet surface. In the presence of isolated particles or localized surface defects, this contamination can lead to the formation of superficial blisters, after detachment of the thin film and its transfer to the receptor plate, or even to the formation of non-transferred zones.
Le retrait de ces contaminants est donc indispensable pour garantir une bonne qualité de mise en contact et de collage.The removal of these contaminants is therefore essential to ensure a good quality of contacting and bonding.
De plus, on sait également d'après l'article de Aditya Agarwal, T. E. Haynes, V. C. Venezia, O. W. Holland, and D. J. Eaglesham, "Efficient production of silicon-on-insulator films by co-implantation of He+ with H+", Applied Physics Letters, vol. 72 (1998), pp. 1086-1088, que si les procédés utilisant la co- implantation d'hydrogène et d'hélium permettent d'utiliser une dose totale d'implantation bien inférieure à celle d'une implantation simple, les défauts de type cloques ("blister" en anglais) sont plus nombreux au niveau de l'interface de collage.In addition, it is also known from the article by Aditya Agarwal, TE Haynes, VC Venezia, OW Holland, and DJ Eaglesham, "Efficient production of silicon-on-insulator films by co-implantation of He + with H + " , Applied Physics Letters, vol. 72 (1998), pp. 1086-1088, that if the processes using the co-implantation of hydrogen and helium make it possible to use a total implantation dose much lower than that of a single implantation, blister-type defects ("blister" in English) are more numerous at the gluing interface.
Par ailleurs, il a été constaté que des substrats de type SOI, dans lesquels la couche d'oxyde enterré est très fine, c'est-à-dire inférieure à 50 nm (50 nanomètres) sont plus difficiles à réaliser, car beaucoup plus sensibles à l'apparition des défauts de type "cloques". II est donc également important de renforcer l'énergie de collage pour élargir les conditions d'utilisation et les possibilités d'application du procédé "Smart Cut ™" précité.Furthermore, it has been found that substrates of the SOI type, in which the buried oxide layer is very thin, that is to say less than 50 nm (50 nanometers), are more difficult to produce because much more sensitive to the appearance of defects of the "blistering" type. It is therefore also important to reinforce the bonding energy to extend the conditions of use and the application possibilities of the aforementioned "Smart Cut ™" method.
Enfin, l'énergie de collage doit également être renforcée, afin de favoriser un détachement et un transfert de couche corrects. En effet, l'existence de contaminants à l'interface de collage peut conduire à un détachement de la couche, au niveau de cette interface, et non au niveau de la zone de fragilisation, en créant ainsi des défauts (zones non transférées) sur la plaquette réceptrice, qui correspondent à des résidus sur la plaquette donneuse. Plus l'énergie de collage sera faible et plus la quantité de zones non transférées sera importante.Finally, the bonding energy must also be reinforced, in order to favor a detachment and a correct layer transfer. Indeed, the existence of contaminants at the bonding interface can lead to a detachment of the layer, at this interface, and not at the weakening zone, thereby creating defects (areas not transferred) on the receptor plate, which correspond to residues on the donor wafer. The lower the bonding energy, the greater the amount of non-transferred areas.
D'autre part, dans le cas où l'énergie de collage est faible, l'onde de collage a plus de difficultés à atteindre le bord de la plaquette diamétralement opposé à celui où le collage a été initié et on observe un plus grand nombre de défauts dans cette région. Afin d'améliorer le collage et d'éliminer toutes les particules présentes à la surface des plaquettes à coller, on connaît déjà dans l'état de la technique, plusieurs procédés de traitement de surface, avant collage.On the other hand, in the case where the bonding energy is low, the bonding wave has more difficulties to reach the edge of the wafer diametrically opposite to that where the bonding was initiated and there is a greater number defects in this region. In order to improve the bonding and to eliminate all the particles present on the surface of the wafers to be bonded, several surface treatment processes are known beforehand in the state of the art, before bonding.
Ces traitements comprennent généralement deux étapes successives, à savoir :These treatments generally comprise two successive stages, namely:
-a) une première étape de nettoyage et d'activation chimique,-a) a first step of cleaning and chemical activation,
-b) une seconde étape de nettoyage, effectuée immédiatement avant le collage et dénommée ci-après « nettoyage avant collage ».-b) a second cleaning step, carried out immediately before bonding and hereinafter referred to as "cleaning before bonding".
L'étape de nettoyage a) des surfaces à coller a pour but de : - rendre ces surfaces hydrophiles,The cleaning step a) surfaces to be bonded aims to: - make these surfaces hydrophilic,
- retirer les contaminants, notamment de type hydrocarbure, apparus sur les surfaces des plaquettes suite à l'implantation,removing the contaminants, especially of hydrocarbon type, which appeared on the platelet surfaces following implantation,
- enlever les particules isolées,- remove the isolated particles,
- limiter la rugosité, (à l'échelle atomique) afin de favoriser un rapprochement intime de plaquettes,to limit the roughness (at the atomic scale) in order to favor an intimate approximation of platelets,
L'hydrophilie de surface favorise le collage et permet d'augmenter la valeur de l'énergie de collage en limitant l'apparition de défauts en bord de plaque.Surface hydrophilicity promotes bonding and increases the value of bonding energy by limiting the appearance of defects at the edge of the plate.
On connaît d'après l'état de la technique un tel procédé de nettoyage et d'activation, dénommé "RCA", qui consiste à traiter les surfaces à coller, successivement avec :According to the state of the art, such a cleaning and activation process, called "RCA", which consists of treating the surfaces to be bonded, successively with:
- un premier bain d'une solution connue sous l'acronyme "SCl" (d'après la terminologie anglo-saxonne de "Standard Clean 1" qui signifie "solution de nettoyage standard 1 "), et qui comprend un mélange d'hydroxyde d'ammonium (NH4OH), de peroxyde d'hydrogène (H2O2) et d'eau déionisée, - un second bain d'une solution connue sous l'acronyme "SC2"a first bath of a solution known by the acronym "SCl" (according to the English terminology of "Standard Clean 1" which means "standard cleaning solution 1"), and which comprises a mixture of hydroxide ammonium (NH 4 OH), hydrogen peroxide (H2O2) and deionized water, - a second bath of a solution known by the acronym "SC2"
(d'après la terminologie anglo-saxonne de "Standard Clean 2" qui signifie "solution de nettoyage standard 2"), et qui comprend un mélange d'acide chlorhydrique (HCl), de peroxyde d'hydrogène (H2O2) et d'eau déionisée.(according to the English terminology "Standard Clean 2" which means "standard cleaning solution 2"), and which comprises a mixture of hydrochloric acid (HCl), hydrogen peroxide (H2O2) and deionized water.
Le premier bain est destiné principalement à retirer les particules isolées présentes à la surface de la plaquette et à rendre les surfaces hydrophiles, tandis que le second bain est plutôt destiné à retirer les contaminations métalliques.The first bath is intended primarily to remove the isolated particles present on the surface of the wafer and make the surfaces hydrophilic, while the second bath is rather intended to remove metal contamination.
Toutefois, on a pu constater qu'après la mise en œuvre d'un tel traitement, les surfaces des plaquettes présentent une rugosité, qui peut, dans certains cas, être même plus importante qu'avant le traitement, ce qui altère considérablement leur énergie de collage. On connaît également d'après la demande de brevetHowever, it has been found that after the implementation of such a treatment, the platelet surfaces have a roughness, which can, in some cases, be even greater than before the treatment, which considerably alters their energy lift-off. It is also known from the patent application
WO-2005/096369, un procédé de nettoyage de la surface oxydée d'une plaquette, en vue de son collage sur une autre plaquette. Un tel procédé utilise un mélange d'ammoniaque (NH4OH) et de peroxyde d'hydrogène (H2O2) et permet d'enlever les particules isolées, tout en évitant de créer une rugosité de surface.WO-2005/096369, a method of cleaning the oxidized surface of a wafer, for its bonding to another wafer. Such a process uses a mixture of ammonia (NH 4 OH) and hydrogen peroxide (H2O2) and allows to remove the isolated particles, while avoiding creating a surface roughness.
Par ailleurs, on notera que si le procédé Smart Cut ™ précité comprend de multiples étapes de nettoyage, l'étape b) de nettoyage avant collage est très spécifique, puisqu'elle conditionne la qualité des substrats obtenus après l'étape de report de couche(s). Cette étape a pour but de retirer les particules ayant pu se déposer, lors du temps d'attente entre l'étape de nettoyage a) et le collage. Elle a également pour but de renforcer l'hydrophilie des plaquettes, celle-ci ayant tendance à diminuer de façon importante plus le temps d'attente entre l'étape de nettoyage a) et le collage est long. Cette étape b) de nettoyage est généralement effectuée par brossage des surfaces à coller avec une solution d'eau déionisée, voir par exemple à ce sujet la demande de brevet FR 2 854 493.Moreover, it will be noted that if the aforementioned Smart Cut ™ process comprises multiple cleaning steps, step b) cleaning before bonding is very specific, since it conditions the quality of the substrates obtained after the layer transfer step (s). This step is intended to remove the particles that may have settled during the waiting time between the cleaning step a) and the bonding. It also aims to enhance the hydrophilicity of the pads, the latter having a tendency to significantly decrease the waiting time between the cleaning step a) and the bonding is long. This cleaning step b) is generally carried out by brushing the surfaces to be bonded with a deionized water solution, see for example on this subject the patent application FR 2 854 493.
Avec le procédé en deux étapes précité, il apparaît malheureusement que plus la surface à coller est rendue hydrophile pour limiter le nombre de défauts de transfert, plus la rugosité de surface augmente, en accroissant ainsi la probabilité d'apparition de défauts du type « cloques ».With the aforementioned two-step method, it unfortunately appears that the more the surface to be bonded is rendered hydrophilic in order to limit the number of transfer defects, the greater the surface roughness increases, thereby increasing the probability of the appearance of defects of the "blistering" type. ".
En effet, dans le traitement précité de type RCA, on obtient un plus fort caractère hydrophile par l'emploi d'une solution SCl à température élevée (>70°C). Mais en contrepartie, la surface ainsi traité sera gravée, ce qui augmentera sa rugosité, cette augmentation de la rugosité de surface étant d'autant plus élevée que la température du bain de SCl est élevée.Indeed, in the aforementioned RCA-type treatment, a stronger hydrophilic character is obtained by the use of a SCl solution at high temperature (> 70 ° C.). But in return, the surface thus treated will be etched, which will increase its roughness, this increase of the surface roughness being even higher than the bath temperature SCl is high.
Enfin, une contrainte supplémentaire apparaît également lors de l'utilisation du procédé précité, car il est nécessaire de minimiser le temps d'attente entre les deux étapes a) et b), pour préserver l'hydrophilie des plaquettes traitées et maximiser l'énergie de collage. Lors de la mise en œuvre à l'échelle industrielle du procédé de fabrication, ceci induit des contraintes supplémentaires dans la gestion des lots de plaquettes à traiter.Finally, an additional constraint also appears when using the above-mentioned method, since it is necessary to minimize the waiting time between the two steps a) and b), to preserve the hydrophilicity of the processed wafers and to maximize the energy lift-off. When implementing the manufacturing process on an industrial scale, this induces additional constraints in the management of batches of wafers to be treated.
En conséquence, la présente invention a pour but de remédier aux inconvénients précités et d'introduire une activation chimique des surfaces, lors de l'étape de nettoyage avant collage, réalisée de préférence à température ambiante, de manière à simplifier l'étape préalable a) de nettoyage, voire même à la supprimer.Accordingly, the present invention aims to overcome the aforementioned drawbacks and to introduce a chemical activation of the surfaces, during the cleaning step before bonding, preferably carried out at room temperature, in order to simplify the preliminary step a) cleaning, or even to remove it.
L'invention a également pour but, si l'étape préalable de nettoyage a) est maintenue, de permettre d'augmenter la durée du temps de stockage et d'activation des plaquettes entre cette étape de nettoyage a) et l'étape de nettoyage avant collage conforme à l'invention, tout en conservant une énergie de collage élevée, à l'issue du collage des deux plaquettes.The invention also aims, if the preliminary cleaning step a) is maintained, to increase the duration of the storage and activation time platelets between this cleaning step a) and the cleaning step before bonding according to the invention, while maintaining a high bonding energy, after the bonding of the two wafers.
Enfin, l'étape d'activation conforme à l'invention doit également s'intégrer au mieux dans le procédé industriel de fabrication des substrats de type SOI, déjà existant.Finally, the activation step according to the invention must also be integrated in the best industrial process for manufacturing SOI type substrates, already existing.
A cet effet, l'invention concerne un procédé de traitement de l'une ou de l'autre ou des deux surfaces, dites « de collage » d'une première plaquette, dite "donneuse" et d'une seconde plaquette, dite "réceptrice", destinées à être collées l'une contre l'autre, dans le but de fabriquer une structure utilisée dans le domaine de l'optique, l'électronique ou l'opto-électronique.For this purpose, the invention relates to a method of treating one or the other or both surfaces, called "gluing" a first wafer, called "donor" and a second wafer, called " receiver ", intended to be glued against each other, for the purpose of manufacturing a structure used in the field of optics, electronics or optoelectronics.
Conformément à l'invention, ce procédé comprend une étape de nettoyage et d'activation, effectuée immédiatement avant le collage desdites plaquettes donneuse et réceptrice, par application sur ladite ou lesdites surfaces de collage, d'une solution dite "de traitement de surface", comprenant au moins environ 97 % d'une solution d'ammoniaque (NH4OH) dans de l'eau, de préférence déionisée, selon une concentration massique comprise entre environ 0,05 % et 2 %.According to the invention, this process comprises a cleaning and activation step, carried out immediately before the gluing of said donor and receiver platelets, by application to said one or more bonding surfaces of a so-called "surface treatment" solution. comprising at least about 97% of a solution of ammonia (NH 4 OH) in water, preferably deionized, in a mass concentration of between about 0.05% and 2%.
Selon d'autres caractéristiques avantageuses et non limitatives de l'invention, prises seules ou en combinaison :According to other advantageous and nonlimiting features of the invention, taken alone or in combination:
• la solution de traitement est constituée d'une solution d'ammoniaque (NH4OH) dans de l'eau, de préférence déionisée, selon une concentration massique comprise entre environ 0,05 % et 2 % ;• the treatment solution consists of a solution of ammonia (NH 4 OH) in water, preferably deionized, in a mass concentration of between about 0.05% and 2%;
• la solution de traitement est constituée de 97% environ d'une solution (NH4OH) dans de l'eau, de préférence déionisée, selon une concentration massique comprise entre environ 0,05 % et 2 % et de 3% environ d'agents chélatants et/ou surfactants ;The treatment solution consists of approximately 97% of a solution (NH 4 OH) in water, preferably deionized, in a mass concentration of between approximately 0.05% and 2% and approximately 3% by weight. chelating agents and / or surfactants;
• la solution d'ammoniaque (NH4OH) présente une concentration massique dans l'eau comprise entre environ 0,5 % et 1,6 %, de préférence encore, voisine de 0,8 % ;The ammonia solution (NH 4 OH) has a mass concentration in water of between approximately 0.5% and 1.6%, more preferably around 0.8%;
• l'étape de nettoyage et d'activation est effectuée par application de ladite solution de traitement de surface à une température inférieure ou égale àThe cleaning and activation step is carried out by applying said surface treatment solution at a temperature less than or equal to
70°C ; • la solution de traitement de surface est appliquée lorsque les plaquettes donneuse et réceptrice sont sur la machine de collage ;70 ° C; • the surface treatment solution is applied when the donor and recipient platelets are on the gluing machine;
• la solution de traitement de surface est appliquée directement sur la machine de collage, de préférence pendant une durée comprise entre 10 secondes et 2 minutes ;The surface treatment solution is applied directly to the gluing machine, preferably for a period of between 10 seconds and 2 minutes;
• ladite étape de nettoyage et d'activation est réalisée en effectuant simultanément l'application de ladite solution traitement de surface et le brossage de la surface de collage à traiter ;Said cleaning and activation step is performed by performing simultaneously the application of said surface treatment solution and the brushing of the bonding surface to be treated;
• au moins l'une des deux surfaces de collage est recouverte d'une couche d'oxyde ;At least one of the two bonding surfaces is covered with an oxide layer;
• la plaquette donneuse a subi une implantation d'espèces atomiques avant le collage, de façon à former une zone de fragilisation, délimitant une couche mince à reporter.• the donor wafer has undergone implantation of atomic species before bonding, so as to form a weakening zone, delimiting a thin layer to be transferred.
L'invention concerne également un procédé de fabrication d'une structure destinée à être utilisée dans le domaine de l'optique, l'électronique ou l'opto-électronique.The invention also relates to a method of manufacturing a structure intended to be used in the field of optics, electronics or optoelectronics.
Conformément à l'invention, ce procédé comprend les étapes suivantes :According to the invention, this method comprises the following steps:
- implantation d'espèces atomiques dans une plaquette dite "donneuse", présentant en surface une couche d'oxyde, de façon à y former une zone de fragilisation, délimitant une couche mince,implantation of atomic species in a so-called "donor" wafer, presenting on the surface an oxide layer, so as to form therein an embrittlement zone delimiting a thin layer,
- nettoyage et activation de la surface oxydée de ladite plaquette donneuse, immédiatement avant le collage, conformément au procédé précité,cleaning and activating the oxidized surface of said donor wafer immediately before gluing, in accordance with the aforementioned method,
- collage de ladite surface activée de la plaquette donneuse, sur la surface d'une autre plaquette, dite "réceptrice", éventuellement oxydée, cette surface ayant éventuellement été nettoyée et activée conformément au procédé précité,- Bonding said activated surface of the donor wafer, on the surface of another wafer, said "receiver", optionally oxidized, this surface having optionally been cleaned and activated according to the aforementioned method,
- détachement, au niveau de ladite zone de fragilisation, de façon à prélever et à reporter ladite couche mince et ladite couche d'oxyde, sur ladite plaquette réceptrice. Selon d'autres caractéristiques de l'invention, prises seules ou en combinaison :detachment, at said weakening zone, so as to collect and transfer said thin layer and said oxide layer onto said receptor plate. According to other features of the invention, taken alone or in combination:
• ce procédé comprend une étape de recuit de consolidation entre l'étape de collage et celle de détachement ;This method comprises a consolidation annealing step between the bonding step and the detaching step;
• la plaquette donneuse est réalisée en un matériau semi-conducteur, en silicium ou en silicium contraint. Ce procédé permet notamment de fabriquer une structure de type semi-conducteur sur isolant ou silicium sur isolant (SOI).The donor wafer is made of a semiconductor material, silicon or constrained silicon. This method makes it possible in particular to manufacture a structure of the semiconductor on insulator or silicon on insulator (SOI) type.
D'autres caractéristiques et avantages de l'invention apparaîtront de la description qui va maintenant en être faite, en référence aux dessins annexés, qui en représentent, à titre indicatif mais non limitatif, un mode de réalisation possible.Other features and advantages of the invention will appear from the description which will now be made, with reference to the accompanying drawings, which represent, by way of indication but not limitation, a possible embodiment.
Sur ces dessins :On these drawings:
- les figures la à Id représente les principales étapes d'un procédé de prélèvement et de report de couches, appliqué à la réalisation d'un substrat de type SOI, - la figure 2 est un schéma représentant une technique de mesure de l'énergie de collage entre deux plaquettes,FIGS. 1a to 1d represent the main steps of a method for sampling and transfer of layers, applied to the production of an SOI type substrate; FIG. 2 is a diagram representing a technique for measuring energy gluing between two platelets,
- la figure 3 est un graphique représentant l'énergie de collage τ entre deux plaquettes, en fonction de la température du traitement de recuit, pour des séries de plaquettes ayant subi respectivement soit un procédé de nettoyage et d'activation « témoin », soit le procédé de nettoyage et d'activation avant collage conforme à l'invention,FIG. 3 is a graph representing the bonding energy τ between two wafers, as a function of the temperature of the annealing treatment, for platelet series having respectively undergone either a "control" cleaning and activation method, or the cleaning and activation process before bonding according to the invention,
- la figure 4 est un graphique illustrant les résultats de la mesure du nombre de défauts de transfert dans une couche reportée, à partir de séries de plaquettes ayant subi respectivement soit un procédé de nettoyage et d'activation « témoin », soit le procédé de nettoyage et d'activation avant collage conforme à l'invention,FIG. 4 is a graph illustrating the results of the measurement of the number of transfer defects in a reported layer, from series of platelets having respectively undergone either a "control" cleaning and activation method, or the method of cleaning and activation before bonding according to the invention,
- la figure 5 représente l'évolution de la valeur de l'énergie de collage τ entre deux plaquettes, pour des lots de plaquettes ayant subi un premier traitement de nettoyage, puis un second traitement de nettoyage et d'activation immédiatement avant collage, mais décalé dans le temps par rapport au premier nettoyage, ce second traitement étant soit un nettoyage « témoin », soit un traitement conforme à l'invention.FIG. 5 shows the evolution of the value of the bonding energy τ between two platelets, for batches of platelets having undergone a first cleaning treatment, then a second cleaning and activation treatment immediately before bonding, but shifted in time compared with the first cleaning, this second treatment being either a "control" cleaning or a treatment according to the invention.
Un objectif principal de la présente invention est de diminuer l'importance des défauts et des rugosités de surface, d'au moins l'une de deux plaquettes destinées à être collées l'une contre l'autre, afin d'augmenter l'énergie de collage entre ces plaquettes.A main objective of the present invention is to reduce the importance of defects and surface roughness, of at least one of two plates to be glued against each other, in order to increase the energy bonding between these pads.
L'invention s'applique plus particulièrement à des plaquettes recouvertes d'une couche d'oxyde, cet oxyde étant soit "natif, c'est-à-dire résultant de l'oxydation à l'air libre de la plaquette, soit additionnel et résultant d'un traitement thermique de cette plaquette ou d'un dépôt d'une couche d'oxyde, par exemple. L'invention trouve une application particulière lors de la mise en œuvre d'un procédé de fabrication d'un substrat de type SOI.The invention applies more particularly to platelets covered with an oxide layer, this oxide being either "native", that is to say resulting from the oxidation in the open air of the wafer, or additional and resulting from a thermal treatment of this wafer or deposition of an oxide layer, for example. The invention finds particular application in the implementation of a method of manufacturing an SOI type substrate.
Pour mémoire, les différentes étapes de ce procédé de fabrication sont rappelées ci-après. En faisant référence à la figure la, une première étape consiste à oxyder une plaquette en matériau semi-conducteur 13, de façon à former une plaquette donneuse 10 présentant en surface, une couche d'oxyde 11.For the record, the various stages of this manufacturing process are recalled below. Referring to FIG. 1a, a first step consists in oxidizing a wafer made of semiconductor material 13, so as to form a donor wafer 10 having on the surface an oxide layer 11.
Généralement, cette oxydation résulte d'un traitement thermique ou du dépôt d'une couche d'oxyde, par exemple une couche de SiO2 lorsque la plaquette 13 est réalisée en silicium.Generally, this oxidation results from a heat treatment or the deposition of an oxide layer, for example an SiO 2 layer when the wafer 13 is made of silicon.
En référence à la figure Ib, la plaquette donneuse 10 est soumise, à travers l'une de ses surface oxydées, à une implantation d'espèce(s) atomique(s), telle qu'une implantation d'hydrogène et/ou d'hélium, par exemple.With reference to FIG. 1b, the donor wafer 10 is subjected, through one of its oxidized surfaces, to an implantation of atomic species (s), such as an implantation of hydrogen and / or helium, for example.
L'énergie et les doses de cette implantation sont choisies de façon à former une zone de fragilisation 15, à une profondeur déterminée sous la surface de la plaquette donneuse 10, plus précisément à l'intérieur de la plaquette 13. On forme ainsi une couche mince 16, délimitée d'une part, par la zone de fragilisation 15 et d'autre part, par la couche d'oxyde 11.The energy and the doses of this implantation are chosen so as to form an embrittlement zone 15, at a determined depth below the surface of the donor wafer 10, more precisely inside the wafer 13. thin 16, delimited on the one hand by the weakening zone 15 and on the other hand by the oxide layer 11.
La surface oxydée de la plaquette donneuse 10, ayant subi l'implantation, porte la référence numérique 12. Cette surface 12 et/ou la surface 22 d'une plaquette 20, dite "réceptrice", subissent alors un traitement de nettoyage avant collage, qui sera détaillé ultérieurement.The oxidized surface of the donor wafer 10, which has been implanted, is designated by the reference numeral 12. This surface 12 and / or the surface 22 of a wafer 20, called a "receptor", then undergo a cleaning treatment before bonding. which will be detailed later.
En référence à la figure Ic, on met alors en contact les surfaces 12 et 22, que l'on colle par adhésion moléculaire. A ce stade, une étape de recuit est éventuellement mise en œuvre pour renforcer l'interface de collage 17 entre les plaquettes donneuse 10 et réceptrice 20.With reference to FIG. 1c, the surfaces 12 and 22, which are bonded by molecular adhesion, are then brought into contact with each other. At this stage, an annealing step is optionally implemented to reinforce the bonding interface 17 between the donor and recipient platelets 20.
Enfin, en référence à la figure Id, on apporte une énergie d'origine thermique, mécanique et/ou chimique, suffisante pour effectuer le détachement le long de la zone de fragilisation 15 et détacher ainsi la couche mince 16, du reste 18 de la plaquette donneuse.Finally, with reference to FIG. 1d, an energy of thermal, mechanical and / or chemical origin, sufficient to carry out the detachment along the embrittlement zone 15 and thereby detach the thin layer 16, from the rest 18 of the donor plaque.
On obtient ainsi la structure semi-conductrice sur isolant représentée sur la figure Id, la couche mince 16 prélevée depuis la plaquette donneuse 10 formant la partie semi-conductrice et la couche d'oxyde 11 sous-jacente formant la partie électriquement isolante. Cette structure est référencée 30. Une étape de finition, utilisant, par exemple, un polissage mécano- chimique, est alors éventuellement mise en œuvre pour rattraper d'éventuels défauts ou rugosités apparus lors du détachement de la couche mince 16.The semiconductor-on-insulator structure shown in FIG. 1D is thus obtained, the thin layer 16 taken from the donor wafer 10 forming the semiconductor portion and the underlying oxide layer 11 forming the electrically insulating portion. This structure is referenced 30. A finishing step, using, for example, a chemical-mechanical polishing, is then optionally implemented to make up for any defects or roughness occurring during the detachment of the thin layer 16.
La structure finale 30 ainsi obtenue est destinée à des applications dans le domaine de la microélectronique, l'optique ou l'optoélectronique.The final structure 30 thus obtained is intended for applications in the field of microelectronics, optics or optoelectronics.
Bien que cela ne soit pas représenté sur les figures, la plaquette réceptrice 20 pourrait éventuellement être recouverte d'une couche d'oxyde, notamment d'oxyde natif.Although this is not shown in the figures, the receptor plate 20 could possibly be covered with a layer of oxide, in particular native oxide.
L'objectif de l'invention est de fournir un procédé de nettoyage et d'activation, des surfaces à coller, c'est-à-dire dans l'exemple précité, des surfaces 12 et/ou 22. Ce procédé permet non seulement d'éliminer les contaminants ou les particules isolées, mais également d'activer les surfaces à coller.The object of the invention is to provide a method of cleaning and activation, surfaces to be bonded, that is to say in the above example, surfaces 12 and / or 22. This method not only allows to remove contaminants or isolated particles, but also to activate surfaces to stick.
Ainsi, lors de la mise en contact de deux plaquettes, leur adhésion se trouve renforcée, lorsque leurs surfaces de collage respectives (ou au moins l'une d'entre elles) ont été activées. Cette adhésion est facilitée grâce au caractère hydrophile des surfaces à coller et correspond la plupart du temps à une interaction moléculaire entre les atomes d'hydrogène présents à la surface des plaquettes à coller.Thus, when two platelets come into contact, their adhesion is enhanced when their respective bonding surfaces (or at least one of them) have been activated. This adhesion is facilitated by the hydrophilic nature of the surfaces to be bonded and corresponds most of the time to a molecular interaction between the hydrogen atoms present on the surface of the wafers to be bonded.
On pourra se référer par exemple à l'article de R.Stengl et al., «A modelfor the silicon wafer bonding process », Japanese Journal of Applied Physics, vol.28, n°10, October, 1989, pp 1735-1741 pour la description des phénomènes d'activation de surface et de collage hydrophile.Reference may be made, for example, to the article by R. Stengl et al., "A model for the silicon wafer bonding process", Japanese Journal of Applied Physics, vol.28, No. 10, October, 1989, pp. 1735-1741. for the description of surface activation and hydrophilic bonding phenomena.
Conformément à l'invention, la demanderesse a observé que le traitement des surfaces de collage de deux plaquettes à coller, ou d'au moins l'une de ces surfaces, à l'aide d'une solution spécifique permettait d'accroître l'énergie de collage entre ces deux plaquettes. Dans la suite de la description et des revendications, cette solution est dite "de traitement de surface".According to the invention, the applicant has observed that the treatment of the bonding surfaces of two wafers to be bonded, or at least one of these surfaces, with the aid of a specific solution made it possible to increase the bonding energy between these two wafers. In the following description and claims, this solution is called "surface treatment".
Cette solution de traitement de surface comprend au moins environ 97% d'une solution d'ammoniaque (NH4OH) dans de l'eau, de préférence déionisée, selon une concentration massique comprise entre environ 0,05 % et 2 %.This surface treatment solution comprises at least about 97% of a solution of ammonia (NH 4 OH) in water, preferably deionized, in a mass concentration of between about 0.05% and 2%.
Selon un premier mode de réalisation de l'invention, la solution de traitement de surface est constituée d'une solution d'ammoniaque (NH4OH) dans de l'eau, de préférence déionisée, selon une concentration massique comprise entre environ 0,05 % et 2 %, Cette solution d'ammoniaque est une solution pure, c'est-à-dire une solution dont la concentration en polluant du type contaminants métalliques (cuivre, fer, chrome, titane, nickel, aluminium) et/ou contaminants alcalins, (lithium, sodium, calcium, potassium, etc..) ne dépasse pas une concentration de 10 ppt (partie par trillion) pour chaque élément.According to a first embodiment of the invention, the surface treatment solution consists of a solution of ammonia (NH 4 OH) in water, preferably deionized, in a mass concentration of between about 0, 05% and 2%, This solution of ammonia is a pure solution, that is to say a solution whose concentration of pollutant type metallic contaminants (copper, iron, chromium, titanium, nickel, aluminum) and / or alkaline contaminants, (lithium, sodium, calcium, potassium, etc.) do not exceed a concentration of 10 ppt (part per trillion) for each element.
Selon un second mode de réalisation de l'invention, on utilise une solution de traitement de surface constituée de 97 % environ de la solution d'ammoniaque précitée et de 3 % environ d'agents chélatants et/ou surfactants.According to a second embodiment of the invention, a surface treatment solution consisting of approximately 97% of the abovementioned ammonia solution and approximately 3% of chelating agents and / or surfactants is used.
Ces agents chélatants permettent en effet de fixer les contaminants, tels que les métaux ou les ions en solution, qui sont souvent présents dans l'ammoniaque disponible industriellement et qui risqueraient de rester piégés au niveau de l'interface de collage, en venant ainsi modifier les caractéristiques électriques du substrat final obtenu. Le surfactant permet d'augmenter l'efficacité d'enlèvement des particules susceptibles de conduire à la formation de cloques superficielles.These chelating agents indeed make it possible to fix the contaminants, such as metals or ions in solution, which are often present in the commercially available ammonia and which might remain trapped at the bonding interface, thereby modifying the electrical characteristics of the final substrate obtained. The surfactant makes it possible to increase the efficiency of removal of particles that can lead to the formation of superficial blisters.
De préférence, la concentration massique de la solution d'ammoniaque est comprise entre 0,5 % et 1,6 %, ou mieux encore voisine de 0,8 %.Preferably, the mass concentration of the ammonia solution is between 0.5% and 1.6%, or better still close to 0.8%.
De façon avantageuse, car plus simple à mettre en œuvre industriellement, la solution d'ammoniaque précitée est utilisée à température ambiante. Elle peut toutefois être appliquée à des températures supérieures mais ne dépassant pas de préférence 70°C. En effet, à des températures supérieures, la rugosité des surfaces augmente fortement, ce qui conduit à une augmentation du nombre de défauts du type « cloque ».Advantageously, because easier to implement industrially, the ammonia solution mentioned above is used at room temperature. It can, however, be applied at higher temperatures but preferably not exceeding 70 ° C. Indeed, at higher temperatures, the roughness of the surfaces increases sharply, which leads to an increase in the number of defects of the "blister" type.
Le traitement de nettoyage et d'activation précité est réalisé immédiatement avant le collage, de préférence directement sur la machine de collage, afin de réactiver l'hydrophilie des plaquettes mises en contact, même si celles-ci ont été en attente pendant plusieurs heures après l'étape de nettoyage, comme cela sera détaillé ultérieurement.The aforementioned cleaning and activation treatment is carried out immediately before gluing, preferably directly on the gluing machine, in order to reactivate the hydrophilicity of the wafers put in contact, even if they have been waiting for several hours after the cleaning step, as will be detailed later.
La solution d'activation peut être distribuée, soit directement sur les plaquettes à traiter sans brossage, soit directement sur les brosses utilisées pour l'activation, soit sur les plaquettes, avant un brossage ultérieur.The activating solution can be distributed, either directly on the wafers to be treated without brushing, or directly on the brushes used for activation or on the wafers, before a subsequent brushing.
Cette technique de brossage est décrite, par exemple, dans le document FR 2 854 493 précité.This brushing technique is described, for example, in the document FR 2 854 493 mentioned above.
La solution ammoniacale est de préférence délivrée pendant une durée de 10 secondes à 2 minutes, de préférence de 30 secondes à 1 minute, à un débit de l'ordre de 1,5 1/mn et ce, directement au niveau de l'équipement de collage, par exemple à l'aide d'un bras distributeur.The ammonia solution is preferably delivered for a period of 10 seconds to 2 minutes, preferably 30 seconds to 1 minute, at a flow rate of the order of 1.5 1 / min and directly at the gluing equipment, for example using a distributor arm.
Selon une variante, la solution ammoniacale peut être distribuée à partir d'un équipement spécifique de nettoyage, par exemple par pulvérisation (équipement du type "single wafer") ou du type bain (équipement du type "wet bench").According to one variant, the ammoniacal solution may be dispensed from specific cleaning equipment, for example by spraying (equipment of the "single wafer" type) or of the bath type (equipment of the "wet bench" type).
La demanderesse a effectué une étude comparative de l'énergie de collage au niveau de l'interface entre deux plaquettes, avec des séries de plaquettes ayant subi respectivement soit un procédé de nettoyage et d'activation dit « témoin », soit le procédé conforme à l'invention.The Applicant has carried out a comparative study of the bonding energy at the interface between two wafers, with series of wafers having respectively undergone either a so-called "control" cleaning and activation process, or the method according to US Pat. the invention.
La demanderesse a utilisé une technique précise de mesure de l'énergie de collage, proposée par Maszara dans le document intitulé "Silicon on insulator by wafer bonding" (J.Electochem.Soc ; volume 138, page 341 (1991)).The applicant has used a precise technique for measuring the bonding energy proposed by Maszara in the document entitled "Silicon on insulator by wafer bonding" (J.Electochem.Soc, volume 138, page 341 (1991)).
Conformément à cette technique, représentée schématiquement sur la figure 2, la demanderesse a inséré une lame 40 sur un ou plusieurs bords de l'ensemble des plaquettes 10 et 20 en contact l'une avec l'autre, au niveau de l'interface de collage 17.According to this technique, shown diagrammatically in FIG. 2, the Applicant has inserted a blade 40 on one or more edges of the set of plates 10 and 20 in contact with each other, at the interface of FIG. collage 17.
L'application d'une force mécanique par l'intermédiaire de la lame 40, dans une direction parallèle au plan de l'interface 17, provoque localement le décollement des deux plaquettes 10 et 20 et une propagation de la zone décollée sur une certaine distance.The application of a mechanical force through the blade 40, in a direction parallel to the plane of the interface 17, locally causes the detachment of the two plates 10 and 20 and a spread of the zone detached for a certain distance .
La longueur L entre le bord extérieur des plaquettes 10, 20 et le point d'arrêt du décollement, qui correspond à la somme de la longueur de la zone localement décollée par la lame 40 et de la longueur de la propagation de la zone de décollement, donne une indication de l'énergie de collage qui existe entre les deux plaquette 10 et 20.The length L between the outer edge of the plates 10, 20 and the stopping point of the detachment, which corresponds to the sum of the length of the area locally peeled off by the blade 40 and the length of the propagation of the separation zone gives an indication of the bonding energy that exists between the two wafers 10 and 20.
En effet, la fin du décollement correspond à un équilibre entre l'énergie de collage et la déformation élastique caractérisant le décollement.Indeed, the end of the separation corresponds to a balance between the bonding energy and the elastic deformation characterizing the detachment.
On calcule ainsi à partir d'une relation entre la longueur de la zone décollée L et l'énergie de surface, une énergie de collage moyenne τ.Thus, from a relationship between the length of the unglued zone L and the surface energy, a mean bonding energy τ is calculated.
On pourra par exemple se référer à la formule suivante tirée du document de Maszara :For example, we can refer to the following formula taken from the Maszara document:
3.RtIy2 τ = —3.RtIy 2 τ = -
32.L4 E étant le module d'Young du matériau présent à l'interface entre les deux plaquettes 10 et 20 ; y étant la demi-épaisseur de la lame ; t étant l'épaisseur de chaque plaquette. L'étude comparative précitée a été réalisée à partir de plusieurs lots de structures comprenant deux plaquettes de silicium de huit pouces (200 mm), dont l'une a été oxydée et a subi une étape d'implantation d'atomes d'hydrogène, ces deux plaquettes étant assemblées par collage par adhésion moléculaire.32.L 4 E being the Young's modulus of the material present at the interface between the two plates 10 and 20; y being the half-thickness of the blade; t being the thickness of each wafer. The abovementioned comparative study was carried out from several lots of structures comprising two eight-inch (200 mm) silicon wafers, one of which was oxidized and underwent a step of implantation of hydrogen atoms. these two wafers being assembled by bonding by molecular adhesion.
Les résultats obtenus sont représentés sur le graphique de la figure 3. L'énergie de collage τ entre les deux plaquettes a été mesurée par la méthode décrite précédemment.The results obtained are shown in the graph of FIG. 3. The bonding energy τ between the two platelets was measured by the method described above.
La figure 3 représente l'énergie de collage τ, en fonction de la température d'un éventuel traitement de recuit (dit "traitement de consolidation"), effectué pendant 2 heures. Certaines des structures n'ont pas subi ce traitement ultérieur de consolidation (résultats obtenus lorsque la température est voisine de 20°C), et d'autres ont subi ce traitement pendant 2 heures, à diverses températures.FIG. 3 represents the bonding energy τ, as a function of the temperature of a possible annealing treatment (called "consolidation treatment"), carried out for 2 hours. Some of the structures did not undergo this subsequent consolidation treatment (results obtained when the temperature is close to 20 ° C), and others have undergone this treatment for 2 hours, at various temperatures.
La courbe en traits pointillés représente les résultats obtenus avec les lots, dans lesquels les surfaces de collage des plaquettes ont subi un traitement de rinçage à l'eau et d'activation simultanée par brossage, ce traitement étant réalisé immédiatement avant collage. Ce traitement est dénommé dans la suite de la description traitement « témoin ».The dotted line curve represents the results obtained with the batches, in which the platelet bonding surfaces have undergone a water rinsing treatment and simultaneous brushing activation, this treatment being carried out immediately before bonding. This treatment is hereinafter referred to as "control" treatment.
La courbe en trait plein représente les résultats obtenus avec les lots, dans lesquels les surfaces de collage des plaquettes ont subi le traitement de nettoyage et d'activation conforme à l'invention.The solid line represents the results obtained with the batches, in which the platelet bonding surfaces have undergone the cleaning and activation treatment in accordance with the invention.
Ce traitement, effectué immédiatement avant le collage, a consisté à appliquer une solution d'ammoniaque (NH4OH) dans de l'eau déionisée, selon une concentration massique de 0.5 %, à température ambiante, cette solution étant distribuée sur les brosses, lors du brossage des plaquettes. A la vue de ces résultats, on constate donc que, quelle que soit la température à laquelle est effectué le traitement de consolidation ultérieur, la valeur de l'énergie de collage τ obtenue est supérieure avec le procédé d'activation conforme à l'invention. Cette augmentation est encore renforcée lorsque le traitement de consolidation est supérieur à 300°C. Une seconde étude comparative a été effectuée, afin de mesurer le nombre de défauts de transfert apparaissant dans le film mince 16 et la couche d'oxyde 11, après détachement le long de la zone de fragilisation 15.This treatment, carried out immediately before the bonding, consisted in applying a solution of ammonia (NH 4 OH) in deionized water, in a mass concentration of 0.5%, at room temperature, this solution being distributed on the brushes, when brushing the pads. In view of these results, it is therefore found that whatever the temperature at which the subsequent consolidation treatment is carried out, the value of the bonding energy τ obtained is greater with the activation method according to the invention. . This increase is further enhanced when the consolidation treatment is greater than 300 ° C. A second comparative study was carried out in order to measure the number of transfer defects appearing in the thin film 16 and the oxide layer 11, after detachment along the embrittlement zone 15.
Des lots de plaquettes similaires à celles décrites pour l'essai précité ont été utilisés.Batches of platelets similar to those described for the above test were used.
La figure 4 représente les résultats de cette étude.Figure 4 shows the results of this study.
L'axe des ordonnées représente le nombre de défauts de transfert N mesurés, par plaquette.The ordinate axis represents the number of transfer defects N measured, per plate.
L'axe des abscisses représente les résultats obtenus, d'une part avec les lots témoins Te, pour lesquels l'étape de traitement de surface a été effectuée selon le procédé « témoin » précité, et d'autre part, avec les lots I, dans lesquels l'étape de nettoyage et d'activation a été effectuée conformément à l'invention, comme décrit en liaison avec la figure 3.The abscissa axis represents the results obtained, on the one hand with the control batches Te, for which the surface treatment step was carried out according to the "control" method mentioned above, and on the other hand, with the batches I , in which the cleaning and activation step has been carried out in accordance with the invention, as described with reference to FIG.
Le nombre moyen de défauts de transfert N dans le premier cas est de 4,09, alors qu'il est voisin de 0.83 dans le second.The average number of transfer defects N in the first case is 4.09, while it is close to 0.83 in the second case.
Une couche mince, reportée sur une plaquette réceptrice, après que les surfaces de collage des plaquettes donneuse et réceptrice aient subi le traitement d'activation conforme à l'invention, présente donc en moyenne presque cinq fois moins de défauts de transfert, qu'une couche mince obtenue après le traitement « témoin ».A thin layer, postponed on a receptor plate, after the bonding surfaces of the donor and recipient platelets have undergone the activation treatment in accordance with the invention, therefore has on average almost five times less transfer defects than thin layer obtained after the "control" treatment.
Enfin, une troisième série d'essais comparatifs a été effectuée, afin de mesurer la valeur de l'énergie de collage τ, entre une plaquette donneuse, oxydée et implantée, et une plaquette réceptrice, en fonction du temps d'attente entre une première étape de nettoyage classique des surfaces à coller et le collage proprement dit, ces plaquettes ayant en outre subit un traitement de nettoyage et d'activation immédiatement avant le collage.Finally, a third series of comparative tests was carried out, in order to measure the value of the bonding energy τ, between an oxidized and implanted donor wafer and a receptor plate, as a function of the waiting time between a first conventional cleaning step of the surfaces to be bonded and the actual bonding, these pads having further undergo a cleaning and activation treatment immediately before bonding.
Les deux plaquettes étaient en silicium et mesuraient huit pouces de diamètre (200 mm).Both wafers were silicon and measured eight inches in diameter (200 mm).
Le premier traitement de nettoyage était du type RCA précité. Le traitement de nettoyage et d'activation conforme à l'invention a été réalisé par brossage, sous une solution d'ammoniaque diluée, à une concentration massique inférieure à 0,5 %, dans de l'eau déionisée.The first cleaning treatment was of the aforementioned RCA type. The cleaning and activation treatment according to the invention was carried out by brushing, under a dilute ammonia solution, at a mass concentration of less than 0.5%, in deionized water.
Sur la figure 5, la courbe en trait plein représente les résultats obtenus, avec des plaquettes ayant subi le traitement de surface « témoin » décrit conjointement avec les figures 3 et 4. La courbe en pointillés représente les résultats obtenus avec des plaquettes ayant subi le traitement de nettoyage et d'activation conforme à l'invention.In FIG. 5, the solid line represents the results obtained with platelets having undergone the "control" surface treatment described in conjunction with FIGS. 3 and 4. The dotted line represents the results obtained with platelets having undergone the cleaning and activation treatment according to the invention.
Ces résultats montrent que, non seulement l'énergie de collage τ est accrue, lorsque l'on utilise le traitement conforme à l'invention, mais également que cette énergie de collage diminue seulement très légèrement entre 0 et 14 heures 30 d'attente entre le premier nettoyage et le collage final, et qu'elle se stabilise ensuite dans le temps.These results show that, not only is the bonding energy τ increased, when using the treatment according to the invention, but also that this bonding energy decreases only slightly between 0 and 14 hours of waiting between the first cleaning and the final bonding, and then stabilize in time.
De façon générale, la demanderesse a mis en évidence l'intérêt de mettre en œuvre le procédé de nettoyage et d'activation conforme à l'invention, dans un procédé de prélèvement et de report de couche, et plus précisément dans la fabrication d'un substrat de type SOI.In general, the applicant has highlighted the interest of implementing the cleaning and activation method according to the invention, in a method of sampling and transfer of layer, and more specifically in the manufacture of an SOI type substrate.
Le procédé conforme à l'invention permet d'augmenter l'énergie de collage, ce qui permet d'être moins exigeant concernant les critères de réalisation d'un premier nettoyage effectué un certain temps avant le collage, voire même de supprimer complètement celui-ci.The method according to the invention makes it possible to increase the bonding energy, which makes it possible to be less demanding concerning the criteria for carrying out a first cleaning carried out a certain time before bonding, or even to completely eliminate it. this.
Ceci permet de simplifier et d'homogénéiser les étapes de préparation des surfaces, effectuées dans une ligne de production avant le collage proprement dit. De plus, le procédé d'activation conforme à l'invention permet de diminuer le nombre de défauts de transfert en bord de plaquette jusqu'à moins de un par plaque en moyenne, ce qui permet d'augmenter considérablement la qualité de la couche mince dans laquelle les futurs composants électroniques seront réalisés.This simplifies and homogenizes the surface preparation steps performed in a production line before the actual bonding. In addition, the activation method according to the invention makes it possible to reduce the number of edge plate transfer defects to less than one per plate on average, thereby considerably increasing the quality of the thin layer. in which the future electronic components will be made.
Enfin, la présente invention ne se limite pas à un procédé d'activation destiné au collage de deux plaquettes de silicium, dont au moins l'une est recouverte d'une couche d'oxyde de silicium, mais peut s'étendre à tout type de matériau, tel que du silicium contraint ou autre matériau semi-conducteur pouvant être employés dans la technologie Smart Cut ™. Finally, the present invention is not limited to an activation method for bonding two silicon wafers, at least one of which is coated with a silicon oxide layer, but can be extended to any type of material, such as constrained silicon or other semiconductor material that can be used in Smart Cut ™ technology.

Claims

REVENDICATIONS
1. Procédé de traitement de l'une ou de l'autre ou des deux surfaces (12, 22), dites « de collage » d'une première plaquette (10), dite "donneuse" et d'une seconde plaquette (20), dite "réceptrice", destinées à être collées l'une contre l'autre, dans le but de fabriquer une structure utilisée dans le domaine de l'optique, l'électronique ou l'optoélectronique, caractérisé en ce qu'il comprend une étape de nettoyage et d'activation, effectuée immédiatement avant le collage desdites plaquettes donneuse (10) et réceptrice (20), par application sur ladite ou lesdites surfaces de collage (12, 22), d'une solution dite "de traitement de surface", comprenant au moins environ 97 % d'une solution d'ammoniaque (NH4OH) dans de l'eau, de préférence déionisée, selon une concentration massique comprise entre environ 0,05 % et 2 %.1. A method of treating one or the other or both surfaces (12, 22), called "bonding" a first wafer (10), called "donor" and a second wafer (20). ), said "receiver", intended to be glued against each other, for the purpose of manufacturing a structure used in the field of optics, electronics or optoelectronics, characterized in that it comprises a cleaning and activation step, carried out immediately before bonding said donor (10) and receiving (20) platelets, by applying to said one or more bonding surfaces (12, 22) a so-called "treatment solution". surface ", comprising at least about 97% of a solution of ammonia (NH 4 OH) in water, preferably deionized, in a mass concentration of between about 0.05% and 2%.
2. Procédé selon la revendication 1, caractérisé en ce que la solution de traitement est constituée d'une solution d'ammoniaque (NH4OH) dans de l'eau, de préférence déionisée, selon une concentration massique comprise entre environ 0,05 % et 2 %.2. Method according to claim 1, characterized in that the treatment solution consists of a solution of ammonia (NH 4 OH) in water, preferably deionized, in a mass concentration of between about 0.05 % and 2%.
3. Procédé selon la revendication 1, caractérisé en ce que la solution de traitement est constituée de 97 % environ d'une solution d'ammoniaque (NH4OH) dans de l'eau, de préférence déionisée, selon une concentration massique comprise entre environ 0,05 % et 2 % et de 3% environ d'agents chélatants et/ou surfactants.3. Method according to claim 1, characterized in that the treatment solution consists of about 97% of a solution of ammonia (NH 4 OH) in water, preferably deionized, in a mass concentration between about 0.05% and 2% and about 3% of chelating agents and / or surfactants.
4. Procédé selon l'une des revendications précédentes, caractérisé en ce que la solution d'ammoniaque (NH4OH) présente une concentration massique dans l'eau comprise entre environ 0,5 % et 1,6 %.4. Method according to one of the preceding claims, characterized in that the ammonia solution (NH 4 OH) has a mass concentration in water of between about 0.5% and 1.6%.
5. Procédé selon la revendication 4, caractérisé en ce que la solution d'ammoniaque (NH4OH) présente une concentration massique dans l'eau voisine de5. Method according to claim 4, characterized in that the ammonia solution (NH 4 OH) has a mass concentration in the water close to
0,8 %.0.8%.
6. Procédé selon l'une quelconque des revendications précédentes, caractérisé en ce que l'étape de nettoyage et d'activation est effectuée par application de ladite solution de traitement de surface à une température inférieure ou égale à 70°C.6. Method according to any one of the preceding claims, characterized in that the cleaning and activation step is performed by applying said surface treatment solution at a temperature of less than or equal to 70 ° C.
7. Procédé selon l'une quelconque des revendications précédentes, caractérisé en ce que la solution de traitement de surface est appliquée lorsque les plaquettes donneuse (10) et réceptrice (20) sont sur la machine de collage. 7. Method according to any one of the preceding claims, characterized in that the surface treatment solution is applied when the donor (10) and receiving (20) platelets are on the gluing machine.
8. Procédé selon l'une quelconque des revendications précédentes, caractérisé en ce que la solution de traitement de surface est appliquée pendant une durée comprise entre 10 secondes et 2 minutes.8. Method according to any one of the preceding claims, characterized in that the surface treatment solution is applied for a period of between 10 seconds and 2 minutes.
9. Procédé d'activation selon l'une quelconque des revendications précédentes, caractérisé en ce que ladite étape de nettoyage et d'activation est réalisée en effectuant simultanément l'application de ladite solution de traitement de surface et le brossage de la surface de collage (12, 22) à traiter.9. Activation method according to any one of the preceding claims, characterized in that said cleaning and activation step is performed by simultaneously applying said surface treatment solution and brushing the bonding surface. (12, 22) to be treated.
10. Procédé selon l'une quelconque des revendications précédentes, caractérisé en ce qu'au moins l'une des deux surfaces de collage (12, 22) est recouverte d'une couche d'oxyde.10. Method according to any one of the preceding claims, characterized in that at least one of the two bonding surfaces (12, 22) is covered with an oxide layer.
11. Procédé selon l'une quelconque des revendications précédentes, caractérisé en ce que la plaquette donneuse (10) a subi une implantation d'espèces atomiques avant le collage, de façon à former une zone de fragilisation (15), délimitant une couche mince (16) à reporter. 11. Method according to any one of the preceding claims, characterized in that the donor wafer (10) has undergone implantation of atomic species before bonding, so as to form a weakening zone (15) delimiting a thin layer. (16) to be reported.
12. Procédé de fabrication d'une structure (30) destinée à être utilisée dans le domaine de l'optique, l'électronique ou l'optoélectronique, caractérisé en ce qu'il comprend les étapes suivantes : implantation d'espèces atomiques dans une plaquette dite "donneuse" (10), présentant en surface une couche d'oxyde (18), de façon à y former une zone de fragilisation (15), délimitant une couche mince (16), nettoyage et activation de la surface oxydée (12) de ladite plaquette donneuse (10), immédiatement avant le collage, conformément au procédé selon l'une quelconque des revendications précédentes, collage de ladite surface (12) activée de la plaquette donneuse (10), sur la surface (22) d'une autre plaquette (20), dite "réceptrice", éventuellement oxydée, cette surface (22) ayant éventuellement été nettoyée et activée conformément au procédé selon l'une quelconque des revendications précédentes, détachement, au niveau de ladite zone de fragilisation (15), de façon à prélever et à reporter ladite couche mince (16) et ladite couche d'oxyde (18), sur ladite plaquette réceptrice (20).12. A method of manufacturing a structure (30) intended to be used in the field of optics, electronics or optoelectronics, characterized in that it comprises the following steps: implantation of atomic species into a said "donor" wafer (10), having on the surface an oxide layer (18), so as to form therein an embrittlement zone (15) delimiting a thin layer (16), cleaning and activating the oxidized surface ( 12) of said donor wafer (10), immediately prior to bonding, according to the method of any one of the preceding claims, bonding said activated surface (12) of the donor wafer (10) to the surface (22) of said a further plate (20), said "receiver", optionally oxidized, this surface (22) having optionally been cleaned and activated in accordance with the method according to any one of the preceding claims, detachment at said weakening zone (15). ) , so as to pick up and carry said thin layer (16) and said oxide layer (18) onto said receiver board (20).
13. Procédé selon la revendication 12, caractérisé en ce qu'il comprend une étape de recuit de consolidation entre l'étape de collage et celle de détachement. 13. The method of claim 12, characterized in that it comprises a consolidation annealing step between the bonding step and the detachment step.
14. Procédé de fabrication d'une structure semi-conductrice sur isolant (30) selon la revendication 12 ou 13, caractérisé en ce que la plaquette donneuse (10) est réalisée en un matériau semi-conducteur.14. A method of manufacturing a semiconductor structure on insulator (30) according to claim 12 or 13, characterized in that the donor wafer (10) is made of a semiconductor material.
15. Procédé selon l'une des revendications 12 à 14, caractérisé en ce que la plaquette donneuse (10) est réalisée en silicium contraint.15. Method according to one of claims 12 to 14, characterized in that the donor wafer (10) is made of constrained silicon.
16. Procédé de fabrication d'une structure (30) de type silicium sur isolant (SOI), selon la revendication 14, caractérisé en ce que la plaquette donneuse (10) est réalisée en silicium. 16. A method of manufacturing a structure (30) of the silicon-on-insulator (SOI) type, according to claim 14, characterized in that the donor wafer (10) is made of silicon.
EP05823924A 2004-12-24 2005-12-21 Method for treating the surface of a wafer Withdrawn EP1829099A1 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
FR0413922A FR2880185B1 (en) 2004-12-24 2004-12-24 PROCESS FOR PROCESSING A WAFER SURFACE
FR0413930A FR2880186B1 (en) 2004-12-24 2004-12-24 PROCESS FOR PROCESSING A WAFER SURFACE
PCT/EP2005/057003 WO2006069945A1 (en) 2004-12-24 2005-12-21 Method for treating the surface of a wafer

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EP1829099A1 true EP1829099A1 (en) 2007-09-05

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Families Citing this family (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2868599B1 (en) * 2004-03-30 2006-07-07 Soitec Silicon On Insulator OPTIMIZED SC1 CHEMICAL TREATMENT FOR CLEANING PLATELETS OF SEMICONDUCTOR MATERIAL
FR2890489B1 (en) * 2005-09-08 2008-03-07 Soitec Silicon On Insulator METHOD FOR MANUFACTURING A SEMICONDUCTOR TYPE HETEROSTRUCTURE ON INSULATION
FR2920912B1 (en) * 2007-09-12 2010-08-27 S O I Tec Silicon On Insulator Tech METHOD FOR MANUFACTURING A LAYER TRANSFER STRUCTURE
US7927975B2 (en) 2009-02-04 2011-04-19 Micron Technology, Inc. Semiconductor material manufacture
CN107958835A (en) * 2016-10-14 2018-04-24 上海新昇半导体科技有限公司 A kind of polishing method of semiconductor crystal wafer
FR3102771B1 (en) * 2019-10-31 2021-10-08 Commissariat Energie Atomique BONDING PROCESS OF TWO HYDROPHILIC SURFACES
FR3136107B1 (en) * 2022-05-25 2024-05-31 Commissariat Energie Atomique Direct bonding process assisted by a strong base
FR3136106B1 (en) * 2022-05-25 2024-05-31 Commissariat Energie Atomique Direct bonding process assisted by a basic molecule

Family Cites Families (32)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5392666A (en) * 1977-01-25 1978-08-14 Seiko Epson Corp Manufacture of semiconductor device
JP2738063B2 (en) * 1989-10-05 1998-04-08 富士通株式会社 Method for manufacturing bonded silicon substrate
JP3187109B2 (en) 1992-01-31 2001-07-11 キヤノン株式会社 Semiconductor member and method of manufacturing the same
JPH07183288A (en) 1993-12-24 1995-07-21 Toshiba Corp Semiconductor wafer treating agent
US5916819A (en) * 1996-07-17 1999-06-29 Micron Technology, Inc. Planarization fluid composition chelating agents and planarization method using same
US6896826B2 (en) * 1997-01-09 2005-05-24 Advanced Technology Materials, Inc. Aqueous cleaning composition containing copper-specific corrosion inhibitor for cleaning inorganic residues on semiconductor substrate
US6013563A (en) * 1997-05-12 2000-01-11 Silicon Genesis Corporation Controlled cleaning process
JPH1197379A (en) * 1997-07-25 1999-04-09 Denso Corp Semiconductor substrate and its manufacture
US6211558B1 (en) * 1997-07-18 2001-04-03 Kavlico Corporation Surface micro-machined sensor with pedestal
US6376337B1 (en) * 1997-11-10 2002-04-23 Nanodynamics, Inc. Epitaxial SiOx barrier/insulation layer
JP3697106B2 (en) 1998-05-15 2005-09-21 キヤノン株式会社 Method for manufacturing semiconductor substrate and method for manufacturing semiconductor thin film
JP3385972B2 (en) * 1998-07-10 2003-03-10 信越半導体株式会社 Manufacturing method of bonded wafer and bonded wafer
JP3328250B2 (en) * 1998-12-09 2002-09-24 岸本産業株式会社 Resist residue remover
US6171965B1 (en) * 1999-04-21 2001-01-09 Silicon Genesis Corporation Treatment method of cleaved film for the manufacture of substrates
US6799583B2 (en) * 1999-05-13 2004-10-05 Suraj Puri Methods for cleaning microelectronic substrates using ultradilute cleaning liquids
US6653209B1 (en) * 1999-09-30 2003-11-25 Canon Kabushiki Kaisha Method of producing silicon thin film, method of constructing SOI substrate and semiconductor device
JP3307375B2 (en) * 1999-10-04 2002-07-24 日本電気株式会社 Method for manufacturing semiconductor device
JP3943782B2 (en) * 1999-11-29 2007-07-11 信越半導体株式会社 Reclaimed wafer reclaim processing method and reclaimed peeled wafer
JP3449474B2 (en) * 2000-02-03 2003-09-22 日本電気株式会社 Composition for surface treatment of semiconductor substrate and surface treatment method
JP2001284558A (en) * 2000-03-31 2001-10-12 Fujitsu Ltd Laminated wafer, producing method therefor and semiconductor device
US6376377B1 (en) * 2000-04-03 2002-04-23 Taiwan Semiconductor Manufacturing Company Post chemical mechanical polish (CMP) planarizing substrate cleaning method employing enhanced substrate hydrophilicity
US6927176B2 (en) * 2000-06-26 2005-08-09 Applied Materials, Inc. Cleaning method and solution for cleaning a wafer in a single wafer process
JP2003051481A (en) * 2001-08-07 2003-02-21 Hitachi Ltd Manufacturing method for semiconductor integrated circuit device
US20030045098A1 (en) * 2001-08-31 2003-03-06 Applied Materials, Inc. Method and apparatus for processing a wafer
US20030162398A1 (en) * 2002-02-11 2003-08-28 Small Robert J. Catalytic composition for chemical-mechanical polishing, method of using same, and substrate treated with same
US7074623B2 (en) * 2002-06-07 2006-07-11 Amberwave Systems Corporation Methods of forming strained-semiconductor-on-insulator finFET device structures
JP2004134675A (en) * 2002-10-11 2004-04-30 Sharp Corp Soi substrate, manufacturing method thereof and display device
US20040126993A1 (en) * 2002-12-30 2004-07-01 Chan Kevin K. Low temperature fusion bonding with high surface energy using a wet chemical treatment
FR2854493B1 (en) * 2003-04-29 2005-08-19 Soitec Silicon On Insulator SCRUBBING TREATMENT OF SEMICONDUCTOR PLATE BEFORE COLLAGE
US7235461B2 (en) * 2003-04-29 2007-06-26 S.O.I.Tec Silicon On Insulator Technologies Method for bonding semiconductor structures together
US6875087B2 (en) * 2003-05-13 2005-04-05 Novellus Systems, Inc. Method for chemical mechanical planarization (CMP) and chemical mechanical cleaning (CMC) of a work piece
US7232759B2 (en) * 2004-10-04 2007-06-19 Applied Materials, Inc. Ammonium hydroxide treatments for semiconductor substrates

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO2006069945A1 *

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TWI333258B (en) 2010-11-11
US20060141746A1 (en) 2006-06-29
WO2006069945A1 (en) 2006-07-06
US7919391B2 (en) 2011-04-05
JP2008526006A (en) 2008-07-17

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