Method for producing a substrate comprising a deposited buried oxide layer or a deposited buried nitride layer

Abstract

A method for producing a substrate comprising a buried oxide layer (1, 10, 20) or a buried nitride layer for the production of electronic components, comprising at least one step for depositing an oxide layer (1, 10, 20) or a nitride layer on a donor substrate (2, 11, 21) and / or an acceptor substrate, and a step for establishing contact between the donor substrate and the acceptor substrate (9, 14, 22), further comprising at least: a first heat treatment of the oxide layer (1, 10, 20) or the nitride layer deposited on the donor substrate (2, 11, 21) and / or the acceptor substrate (9, 14, 22) before connecting the donor substrate (2, 11, 21) with the Acceptor substrate (9, 14, 22) and a second heat treatment of the substrate, which consists of the acceptor substrate (9, 14, 22), the oxide layer (1, 10, 20) or the nitride layer and the entire donor substrate (2, 11, 21) or a part thereof, at a temperature,which is the same as or higher than the temperature applied in the first heat treatment, wherein the second heat treatment is a compression heat treatment, wherein the first heat treatment consists of applying a temperature of 600 to 1000 °C for a period of a few minutes to a few hours in a non-oxidizing inert gas or a mixture of inert gases.

Description

[0001] The present invention relates to a method for producing a substrate comprising a buried oxide layer, and in particular Substrates of the type SeOI (Semiconductor On Insulator), SOI (Silicon On Insulator), sSOI (strained Silicon On Insulator) or UTBOX (Ultra Thin Buried oxides), and it concerns a method for bonding substrates with a deposited oxide. Background of the invention

[0002] In the field of semiconductor substrates, such as SeOI and sSOI substrates, especially for microelectronics, optoelectronics etc., is known to be an electrically insulating layer, such as an oxide or nitride layer, on at least one of the substrates. trained to bond the two substrates brought into contact during their manufacture or to modify the surface of the To protect substrates from chemical contamination and scratching, especially during handling.

[0003] The oxide layer is formed either by direct oxidation, such as thermal or anodic oxidation, or by deposition of a An oxide layer is formed, and the formation of a nitride layer is caused by deposition.

[0004] According to the first process for forming an oxide layer, the thermal oxidation is carried out in an oven in which substrates which for example, made of silicon, and exposed to a temperature between 900 and 1200°C.

[0005] A gas is introduced into the oven to oxidize the substrates, so that an oxide layer grows on the substrates over time. During the In the dry thermal oxidation process, the gas is oxygen, and in the wet thermal oxidation process, the gas is water vapor.

[0006] The thermal oxidation process, and in particular the dry thermal oxidation process, produces an oxide layer which has a high It exhibits high quality, is particularly dense, and has high dielectric strength.

[0007] However, the disadvantage of the method is the low growth rate of the oxide layers.

[0008] The second type of method for forming an oxide layer, i.e. by deposition, includes several methods for depositing a oxide layer, which are known to those skilled in the art.

[0009] Most of these processes consist individually of low-temperature CVD (Chemical Vapor Deposition), LPCVD (Light-Pressure) Chemical Vapor Deposition) or PECVD (Plasma Enhanced Chemical Vapor Deposition).

[0010] These oxide deposits are formed in an oven in which, for example, silicon substrates are heated to a temperature between 300 and will be exposed to 800°C.

[0011] These methods enable the formation of thick oxide layers on the substrates in a relatively short time.

[0012] However, these types of oxide layers are porous. The porosity of these oxide layers leads to a low layer density, through which the quality of the transmission is affected, which is achieved with the method known as "Smart Cut", a method that is used in the Publication “Silicon-On-Insulator Technology: Materials to VLSI” by Jean-Pierre Colinge, 2nd edition, published by Kluwer Academic Publishers, pages 50 and 51, are described.

[0013] The transfer of a layer using the smart-cut method may be of poor quality if the deposited oxide layer is not has been compressed by means of a heat treatment.

[0014] The densification of these oxide layers can be achieved by applying annealing at a temperature between 600 and 1200°C can be reached over a period of between 10 minutes and 6 hours, as described in international patent application WO 2006 / 029651 This heat treatment also makes it possible to remove certain elements, such as carbon, which are deposited during deposition in The oxide is integrated to degas.

[0015] However, during the production of multilayer heterostructures, the application of this heat treatment to densify a layer on The oxide layer deposited on the multilayered substrate is limited to low temperature ranges to prevent the occurrence of defects and the To avoid diffusion of the elements between the different layers of the substrate.

[0016] That is, during the various healing steps in the course of the Smart-Cut process, the degassing of the deposited Oxide layer can lead to the formation of defects.

[0017] It should be noted that the same disadvantages occur with nitride insulating layers. Brief description of the invention

[0018] A first object of the invention is therefore to avoid these disadvantages by providing a method for producing a substrate, which comprises a deposited buried oxide layer, is created for the production of electronic components or the like, through which a A deposited oxide layer, which has the same quality as a thermal oxide layer, forms within the finished substrate.

[0019] For this purpose, the invention proposes a method for producing a substrate with a buried oxide layer for the production electronic components or the like, which includes at least one step for depositing an oxide layer or a nitride layer on a donor substrate and / or an acceptor substrate, as well as a step of establishing contact between the donor substrate and the acceptor substrate The process comprises at least a first heat treatment of the oxide layer or the nitride layer that is on the donor substrate and / or the acceptor substrate is deposited, before connecting the donor substrate to the acceptor, as well as a second heat treatment of the substrate, which consists of the acceptor substrate, the oxide layer and the entire donor substrate or a part thereof, at a temperature includes a temperature that is the same as, or higher than, the temperature applied during the first heat treatment.

[0020] The second heat treatment is a compression heat treatment.

[0021] The first heat treatment consists of maintaining a temperature of 600° to 1000°C for a period of several minutes to several to be applied for hours in a non-oxidizing inert gas or a mixture of inert gases.

[0022] Preferably, the first heat treatment consists of applying a temperature of 800°C for 2 to 4 hours.

[0023] Furthermore, the second heat treatment consists of maintaining a temperature of 1000 to 1200°C for a period of several minutes to to be applied for several hours in a non-oxidizing inert gas or a mixture of inert gases.

[0024] The inert gas or mixture of inert gases used in the inert atmosphere is selected from the following list: Argon (Ar), nitrogen (N2) and xenon (Xe).

[0025] Preferably the oxide precursor is tetraethyl orthosilicate (TEOS), and the silicon nitride precursors are dichlorosilane and ammonia.

[0026] Advantageously, the donor substrate is a multilayer substrate consisting of a silicon support substrate, a silicon-germanium A (SiGe) layer of increasing composition, a relaxed SiGe layer and a layer of stretched silicon are formed.

[0027] According to one implementation variant, the donor substrate and / or the acceptor substrate consists of a silicon substrate. with a (100), (110) or (111) crystal orientation.

[0028] According to a fundamental feature of the invention, the method includes a step of detaching a functional layer from the donor- substrate.

[0029] This step of removing the wear layer is carried out by means of a sequence of the following steps: implantation of ions or gaseous elements from the top of the oxide layer deposited on the donor substrate to create a buried weak zone in the to form donor substrate, and then splitting in the weak zone, causing the detachment of the utility layer.

[0030] The step of implanting ions or gaseous elements is carried out after the first heat treatment, and the step of Splitting in the weak zone is carried out before the second heat treatment.

[0031] The parameters for the implantation of elements are selected such that a weak zone is created in the relaxed SiGe layer of the a multi-layered donor substrate is formed.

[0032] Furthermore, the method includes, before the step of establishing contact between the acceptor substrate and the oxide layer or the The nitride layer deposited on the donor substrate represents a step in preparing the substrate surfaces.

[0033] Another object of the invention is a substrate which is obtained by the method according to the invention.

[0034] For this purpose, the invention proposes a substrate comprising at least one oxide or nitride layer mounted on a donor- substrate and / or an acceptor substrate, wherein the oxide or nitride layer is degassed and has a refractive index that is smaller than is defined as the refractive index of an oxide or nitride layer of the same composition, formed by thermal growth.

[0035] According to a fundamental feature of the substrate according to the invention, the refractive index of the degassed oxide or nitride layer is between 1435 and 1455 for a laser wavelength of 633 nm. Brief description of the drawings

[0036] Further advantages and features will be shown in the following description of the [ ], which serves only as a non-limiting example. Method for producing a substrate according to the invention and as can be seen more clearly from the drawings, wherein:

[0037] Fig. 1 schematically shows the steps of an example of how the method according to the invention is implemented;

[0038] Fig. 2 schematically shows the steps of a second example of how the method according to the invention is implemented,

[0039] Fig. 3 schematically shows steps of a final implementation variant of the method according to the invention;

[0040] Fig. 4 is a diagram showing the change in the thickness of the oxide layer as a function of the duration and temperature of the Heat treatment shows;

[0041] Fig. 5 is a diagram showing the change in the refractive index of the oxide layer as a function of the compression temperature; and

[0042] Fig. 6 shows a comparative table of the etch rate for a thermal oxide and the etch rate for a deposited oxide, which is a has undergone compression according to the invention. Detailed description of the invention

[0043] The inventive method for producing a multilayer and single-layer substrate, which has a buried oxide layer The range of substrates, including SeOI, SOI, and sSOI, is described below. However, it is obvious that the The inventive method can also be adapted to extend to UTBOX substrates and other substrates without thereby deviating from the to deviate from the scope of protection of the invention.

[0044] The method according to the invention comprises, as can be seen with reference to Fig. 1, a first step of depositing a Oxide layer 1 (Fig. 1b) on a multilayer substrate 2, which is referred to as a donor substrate and in this particular embodiment a silicon support substrate 3, a silicon-germanium (SiGe) layer 4 of increasing composition, a relaxed SiGe layer 5 and a Layer 6 contains elongated silicon (Fig. 1a).

[0045] It should be noted that the oxide layer 1 can be replaced by a nitride layer without affecting the scope of protection of the invention. to deviate, whereby the layer is deposited by the reaction of dichlorosilane (DCS, i.e. SiH2Cl2) with ammonia.

[0046] Then, as can be seen with reference to Fig. 1c, a first heat treatment is carried out at a temperature between 600 and 1000°C. over a period of a few minutes to a few hours and preferably at a temperature of 800°C for 2 to 4 hours in a carried out using non-oxidizing inert gas or a mixture of inert gases.

[0047] The inert atmosphere thus produced consists, for example, of argon (Ar), nitrogen (N2) or xenon (Xe) or of a mixture of at least two of these inert gases.

[0048] This first heat treatment at a relatively low temperature causes densification of the oxide layer 1 as well as the degassing of certain elements, while at the same time maintaining a certain degree of porosity of the deposited oxide layer 1.

[0049] The porosity of the oxide layer 1 enables good bonding when it is brought into contact with a second substrate, as shown further below. This will be explained in detail below.

[0050] The degassed oxide or nitride layer 1 has a lower refractive index than that of an oxide or nitride layer of the same chemical composition. Composition formed by thermal growth. The refractive index of the degassed oxide layer (1) is preferably between 1.435 and 1.455 at a laser wavelength of 633 nm of a device for measuring the refractive index, for example by means of Ellipsometry.

[0051] Subsequently, ions and / or gaseous elements 7 are introduced via the top surface of the donor substrate 2, i.e. the oxide layer 1 , implanted to form a weakened buried zone 8 in the donor substrate 2, as shown in Fig. 1d with the dashed line, to train according to the method known as “Smart Cut”, as described in the publication “Silicon-On-Insulator Technology: Materials to VLSI” by Jean-Pierre Colinge, 2nd edition, published by Kluwer Academic Publishers, pages 50 and 51, are described.

[0052] Zone 8 consists of microcavities and is formed in the relaxed SiGe layer 5. This weakened buried zone 8 As will be shown below, this makes it possible to remove part of the donor substrate 2.

[0053] In this step of weakening, preferably an implantation (only hydrogen, only helium, etc.) or a Simultaneous implantation of at least two different atomic elements, for example hydrogen and helium, which are implanted sequentially are used, with helium preferably being implanted before hydrogen.

[0054] In this example, it can be seen that the parameters of the implantation of the elements are selected such that a weak zone 8 in the relaxed SiGe layer 5 of substrate 2 is created.

[0055] However, the parameters of the implantation can be selected such that the weak zone 8 is located in any desired layer of the Donor substrate 2 is located.

[0056] Then, as can be seen with reference to Fig. 1e, an acceptor substrate 9, which consists, for example, of silicon, is connected with the upper Layer of the donor substrate 2 is connected. It is therefore understood that the first heat treatment of the oxide layer 1, which is on the donor- Substrate 2 is deposited, before the donor substrate 2 and the acceptor substrate 9 are connected.

[0057] In the remaining text, the term “connect” is used to describe the close contact between the acceptor substrate 9 and the oxide layer 1 of the donor substrate 2.

[0058] It should be noted that, since the porosity of the oxide layer 1 has been maintained during the first heat treatment, the quality of the The connection is particularly good.

[0059] Furthermore, before connecting the donor substrate 2 with the acceptor substrate 9, the donor substrate 2 and the acceptor substrate 9 are coated with a thin layer of resin. Substrate 9 was cleaned with an ozone mixture and / or a mixture of a composition of the RCA (Radio Corporation of America) type, which It consists of SC1 and SC2 (where SC stands for "Standard Cleaning"), which are familiar to professionals. The surfaces can They can also be brushed, rinsed and dried, but can also undergo a plasma activation step, for example in oxygen or nitrogen, through.

[0060] As can be seen in Fig. 1f, the part of the donor substrate 2 in the weak zone 8 is cut according to the smart-cut method by Heat treatment in an inert atmosphere at a temperature of approximately 500°C and / or under stress removed the material.

[0061] It should be noted that the wear layer 1 can be dissolved by any other means known to those skilled in the art, so for example by diluting the donor substrate 2, for example using a BESOI-type method.

[0062] Then the top side of the relaxed SiGe layer 5, which remains on the donor substrate 2, is coated with any suitable Methods such as CMP (Chemical Mechanical Planarization) are used to remove material until layer 6 is reached. The upper layer of the substrate is formed by elongated silicon (Fig. 1g).

[0063] It should be noted that the top surface of the relaxed SiGe layer 5 that remains can be removed, in particular by The following processes are applied: – a wet oxidation treatment followed by a selective etching step, if the weakened buried zone 8 is formed by simultaneous implantation of elements into the substrate; – a step of the CMP- Polishing, followed by a step of selective etching, when the weakened buried zone 8 is treated by implanting a single element has been trained; and – a simple step of selective etching.

[0064] As can be seen with reference to Fig. 1h, a second oxide or nitride layer 10, which is referred to as a sacrificial layer, is applied to the Layer 6 is deposited from stretched silicon.

[0065] Then a second heat treatment is carried out at a temperature between 1000 and 1200°C for a period of a few minutes. and a few hours and preferably at a temperature of 1100°C for 2 hours in a non-oxidizing inert gas or in a A mixture of inert gases is used. In the same way as before, the resulting inert atmosphere consists, for example, of argon. (Ar), nitrogen (N2) or xenon (Xe) or a mixture of at least two of these inert gases together.

[0066] During this second heat treatment, the buried oxide layer 1 is compacted, and any defects that were initially present in the Any surface layer present on the substrate is removed. Furthermore, this second compaction heat treatment enables the To strengthen substrate interfaces.

[0067] It is obvious that the oxide or nitride layer 1 can be deposited on the acceptor substrate 9 and the arrangement of Acceptor substrate 9 and oxide layer 1 can undergo the first heat treatment before the acceptor substrate 9 and the donor- Substrate 2 come into contact with each other without deviating from the scope of protection of the invention.

[0068] Finally, as can be seen with reference to Fig. 1i, the sacrificial oxide layer 10, which made it possible to form layer 6 from To protect the stretched silicon during the second heat treatment, a hydrofluoric acid (HF) treatment is used to remove the residue, which is then removed. is known to experts.

[0069] The substrate thus obtained, which is shown in Fig. 1i, consists of a lower acceptor substrate 9 and an upper layer 6 made of extended silicon (sSi), wherein the acceptor substrate 9 is separated from the layer 6 of extended silicon by a densified oxide layer 1 is isolated.

[0070] From Fig. 4, which is a diagram showing the change in the thickness of the oxide layer as a function of the duration and temperature of the As heat treatment demonstrates, the densification of the oxide layer occurs progressively and at temperatures below 800°C, which is the first The heat treatment of the inventive process is not complete, and the compression occurs at temperatures of 1000°C and 1100°C, which corresponds to the second heat treatment of the process, is complete. The invention utilizes the change in the nature of the insulating layer and its physicochemical properties for producing the substrate. The final substrate exhibits the following characteristics at the end of the process. an insulating layer of very good quality and with a composition that differs from the insulating layers used in the The substrate is present during its production before the application of the second heat treatment.

[0071] Furthermore, from Fig. 5, which is a diagram showing the change in the refractive index of the oxide layer as a function of the The compression temperature shows that the optical index decreases between 500 and 800°C – this corresponds to the degassing mechanism and compression during the first heat treatment of the inventive process – and that the The optical index increases at temperatures above 800°C, indicating that the compression mechanism is more efficient than degassing during compression. The second heat treatment of the process is dominant, and the change in the optical index results from a reduction in porosity.

[0072] Furthermore, it can be seen from Fig. 6 that the etch rate of the deposited oxide after the heat treatments according to the invention the etch rate of a thermal oxide is similar, so that the quality of the compacted, deposited oxide at the end of the process is comparable to that of a agrees with thermal oxide.

[0073] A specific, non-limiting exemplary embodiment of a substrate produced according to the invention is described below. described with reference to Fig. 1. Example 1:

[0074] An oxide layer 1 (Fig. 1b) is deposited on a multilayer substrate 2, which is referred to as the donor substrate and consisting of a silicon support substrate 3, a silicon-germanium (SiGe) layer 4 of increasing composition, a relaxed SiGe layer 5 and consists of a layer 6 of elongated silicon (Fig. 1a).

[0075] This oxide layer 1 is a silicon oxide made of TEOS (tetraethyl orthosilicate, i.e. Si(OC2H5)4) with a diluting gas, such as for example, oxygen or nitrogen, is formed, for example, according to a method known to those skilled in the art. The dilution The gas is preferably oxygen to limit the amount of hydrocarbons in the deposited oxide layer 1.

[0076] The separation pressure is between 200 and 700 mTorr, preferably 300 mTorr.

[0077] Furthermore, the flow rate of the TEOS precursor is between 200 and 600 sccm, preferably 300 sccm, and the flow rate The oxygen content is between 20 and 100 sccm, preferably 40 sccm.

[0078] Furthermore, the oxide deposition temperature is between 500 and 800°C, preferably between 600 and 700°C.

[0079] The thickness of the oxide layer thus deposited is generally between 1000 and 2000 Å, preferably approximately 1500 Å.

[0080] Then, as can be seen with reference to Fig. 1c, a first heat treatment is carried out at a temperature of approximately 800°C over approximately 2 hours in a non-oxidizing inert gas or a mixture of inert gases.

[0081] Subsequently, gaseous elements 7 are implanted via the top surface of the donor substrate 2, i.e., the oxide layer 1, to be incorporated into the Donor noun rat 2 a weakened buried zone 8, which is shown in Fig. 1d with the dashed lines, corresponding to the one called “Smart to develop the “Cut” known method, as described in the publication “Silicon-On-Insulator Technology; Materials to VLSI” by Jean-Pierre Colinge, 2nd edition, published by Kluwer Academic Publishers, pages 50 and 51, describes it.

[0082] This weakening implantation step is carried out, for example, by introducing hydrogen with an energy of approximately 30 keV and in a A dose of approximately 6 × 1016 at / cm2 is implanted.

[0083] In an alternative implementation, the implantation step can also be carried out by combining hydrogen with an energy of approximately 30 keV and a dose of approximately 1.5 × 1016 at / cm2, and helium with an energy of approximately 50 keV and a dose of approximately 1.5 × 1016 at / cm2 can be implanted simultaneously.

[0084] More generally speaking, simultaneous implantation with a hydrogen energy of approximately 20 to 40 keV and a helium energy carried out at approximately 30 to 60 keV, with doses for both elements being approximately 1 to 2 × 1016 at / cm2.

[0085] In this example, it can be seen that the parameters for the implantation of elements are chosen such that a weak zone 8 in the relaxed SiGe layer 5 of the substrate 2 is formed.

[0086] Then, as can be seen with reference to Fig. 1e, an acceptor substrate 9, which consists, for example, of silicon, is combined with the Top of donor substrate 2 connected.

[0087] In addition, before connecting the acceptor substrate 9 with the donor substrate 2, the donor substrate 2 and the acceptor- Substrate 9 with a mixture of ozone and / or a composition of the RCA (Radio Corporation of America) type, as known to the skilled person is known, and / or cleaned from fully desalinated water by means of brushing, rinsing and drying.

[0088] The step of preparing the surfaces of the substrates could also consist of rinsing the surfaces with plasma in oxygen or nitrogen activated.

[0089] Then, as can be seen with reference to Fig. 1f, the substrate formed by the acceptor substrate 9 and the donor substrate 2 is The arrangement is reversed, and then a portion of the donor substrate 2 is removed from a weak zone 8 according to the smart-cut method using a Heat treatment at a temperature of approximately 500°C was performed.

[0090] Subsequently, the top surface of the relaxed SiGe layer 5, which remained on the donor substrate 2, is coated with any desired suitable methods, such as a method known as CMP (Chemical Mechanical Planarization), are used to remove material until layer 6 is removed. The upper layer of the substrate is formed by elongated silicon (Fig. 1g).

[0091] The upper surface of the relaxed SiGe layer 5 that remains can be removed, in particular, by the following processes The following processes can be applied: – a wet oxidation treatment followed by a selective etching step; – a heat treatment, if the weakened buried zone 8 is formed by implantation or simultaneous implantation of elements into the substrate; – a step of CMP polishing followed by a step of selective etching, if the weakened buried zone 8 is formed by the Implantation of a single element was formed; and – a simple step of selective etching.

[0092] As can be seen with reference to Fig. 1h, a second TEOS oxide layer 10, which is referred to as the sacrificial layer, is applied to the Layer 6 was deposited from stretched silicon with a thickness of approximately 100 Å.

[0093] Then a second heat treatment, a compression heat treatment, is carried out at a temperature of 1100°C for 2 hours in a applied in a non-oxidizing inert atmosphere or a mixture of inert gases.

[0094] Finally, as can be seen with reference to Fig. 1i, the sacrificial oxide layer 10 is treated by means of a hydrofluoric acid treatment. removed.

[0095] In an alternative implementation of the method according to the invention, as can be seen with reference to Fig. 2, the The process involves a first step of depositing an oxide layer 10 (Fig. 2b) on a single-layer substrate 11, which is referred to as the donor substrate. is designated as one that is made, for example, from silicon (Fig. 2a), wherein the silicon has (100), (110) or (111) crystal orientation. could.

[0096] It should be noted that the oxide layer 1 could be replaced by a nitride layer without affecting the scope of protection of the invention. to deviate.

[0097] Then, as can be seen with reference to Fig. 2c, a first heat treatment is carried out at a temperature between 600 and 1000°C. over a period of a few minutes to a few hours, for example 5 minutes to 10 hours, preferably at a temperature of 800°C for 2 to 4 hours, in a non-oxidizing inert gas or a mixture of inert gases.

[0098] The inert gas atmosphere thus generated consists, for example, of argon (Ar), nitrogen (N2) or xenon (Xe) or of a mixture of at least two of these inert gases.

[0099] This first heat treatment at a relatively low temperature initially leads to the densification of the oxide layer 10, but also to Degassing of certain elements, while simultaneously maintaining a specific degree of porosity of the deposited oxide layer 10. Furthermore, the porosity of the oxide layer 10 results in a good bond when it is brought into contact with a second substrate, as shown here. This will be explained in detail below.

[0100] Then ions and / or gaseous elements 12 are implanted through the top surface of the donor substrate 11, i.e. the oxide layer 10, to create a weakened buried zone 13 in the donor substrate 11, as shown in Fig. 2d with the dashed line, accordingly to develop the method known as “Smart Cut”, as described in the publication “Silicon-On-Insulator Technology: Materials to VLSI by Jean-Pierre Colinge, 2nd edition, published by Kluwer Academic Publishers, pages 50 and 51, is described.

[0101] This weakened buried zone 13 allows the detachment of part of the donor substrate 11 .

[0102] In the same way as before, this weakening implantation step preferably includes implantation (only hydrogen, only helium). etc.) or simultaneous implantation of at least two different atomic elements, for example hydrogen and helium, which sequentially are implanted, with the helium preferably being implanted before the hydrogen.

[0103] Then, as can be seen with reference to Fig. 2e, an acceptor substrate 14, which consists, for example, of silicon, i.e., (100)-, (110)- or (111)-Si, connected to the top of the donor substrate 11 , i.e. to the oxide layer 10 .

[0104] Furthermore, before the acceptor substrate 14 is connected to the donor substrate 11, the donor substrate 11 and the Acceptor substrate 14, as described above, purified by any suitable method.

[0105] The arrangement formed by the acceptor substrate 14 and the donor substrate 11 is, as can be seen with reference to Fig. 2f, in the weak zone 13 according to the Smart-Cut method by heat treatment at a temperature of approximately 500°C and / or below Application of voltage solved.

[0106] Then, as can be seen with reference to Fig. 2g, a second heat treatment is carried out at a temperature between 1000 and 1200°C for a period of a few minutes to a few hours and preferably at a temperature of 1100°C for 2 hours in applied to a non-oxidizing gas or a mixture of inert gases. In the same way as before, the inert gas thus produced consists An atmosphere consisting, for example, of argon (Ar), nitrogen (N2) or xenon (Xe), or of a mixture of at least two of these inert gases.

[0107] During this second heat treatment, the buried oxide layer 10 is compacted, and any oxides in the surface layer of the Existing defects in the substrate are eliminated. Furthermore, this second heat treatment strengthens the bonding interfaces.

[0108] The substrate obtained in this way consists, as shown in Fig. 2g, of a lower silicon acceptor substrate 14 and an upper silicon layer, wherein the acceptor substrate 14 is separated from the silicon layer 11 by a densified oxide layer 10.

[0109] A specific, but not limiting, exemplary embodiment of a substrate obtained according to the invention is described below. described with reference to Fig. 2. Example 2:

[0110] A SiO2 oxide layer 10 (Fig. 2b) obtained from a TEOS precursor is deposited on a single-layer substrate using the LPCVD process. Substrate 11, which is referred to as the donor substrate and consists of silicon (Fig. 2a), is deposited.

[0111] The thickness of the oxide layer was between 200 and 500 Å, preferably 200 Å.

[0112] Then, as can be seen with reference to Fig. 2c, a first heat treatment is carried out at a temperature of 750°C for 2 hours in applied to a non-oxidizing inert gas or a mixture of inert gases.

[0113] Subsequently, hydrogen elements 12 are implanted via the top surface of the donor substrate 11, i.e., the oxide layer 10, to be placed in the Donor substrate 11 a weakened buried zone 13, as shown in Fig. 1d with the dashed line, corresponding to the to develop the “Smart Cut” known method, as described in the publication “Silicon-On-Insulator Technology: Materials to VLSI” by Jean-Pierre Colinge, 2nd edition, published by Kluwer Academic Publishers, pages 50 and 51, is described.

[0114] This attenuation implantation step includes, for example, the implantation of hydrogen with an energy of approximately 25 keV and in a dose of approximately 5 × 1016 at / cm2.

[0115] Then, as can be seen with reference to Fig. 2e, an acceptor substrate 14, which also consists of silicon, is connected with the upper layer of donor substrate 11 , i.e. the oxide layer 10 , connected.

[0116] Furthermore, before the acceptor substrate 14 is connected to the donor substrate 11, the donor substrate 11 and the Acceptor substrate 14, as described above, purified by any suitable method.

[0117] As can be seen with reference to Fig. 2f, a part of the donor substrate 11 is placed in the weak zone 13 according to the Smart- The cutting method using heat treatment at a temperature of approximately 500°C has been replaced.

[0118] Then, as can be seen with reference to Fig. 2g, a second compression heat treatment is carried out at a temperature of 1100°C. applied for over 2 hours in a non-oxidizing inert gas or a mixture of inert gases.

[0119] In a final alternative implementation form of the method according to the invention, the method consists in the fact that, as described below As can be seen in Fig. 3, a first substrate is connected to a second substrate.

[0120] The method according to the invention includes a first step of depositing an oxide layer 20 (Fig. 3b) or a nitride layer. a first substrate 21, which is referred to as the donor substrate (Fig. 3a) and is made of any material, such as silicon, GaN etc., exists.

[0121] Then, as can be seen with reference to Fig. 3c, a first heat treatment is carried out at a temperature between 600 and 1000°C. over a period of time between a few minutes and a few hours, preferably at a temperature of 800°C for 2 to 4 hours, in a applied to non-oxidizing inert gas or a mixture of inert gases.

[0122] The inert atmosphere thus created consists, for example, of argon (Ar), nitrogen (N2) or xenon (Xe) or of a mixture of at least two of these inert gases.

[0123] The first heat treatment at a relatively low temperature causes the compaction of the oxide layer 20 and the degassing of certain elements, while maintaining a certain degree of porosity of the deposited oxide layer 20.

[0124] The porosity of the oxide layer 20 enables a good bond when it is brought into contact with a second substrate.

[0125] It is obvious that an oxide or nitride layer could be deposited on any substrate without affecting the substrate. to deviate from the scope of protection of the invention.

[0126] Then, as can be seen with reference to Fig. 3d, a second substrate 22, which is called the acceptor substrate and also made of any material, such as silicon and GaN, is connected to the first substrate 21 by means of the acceptor substrate 22 is brought into close contact with the oxide layer 20 of the donor substrate 21.

[0127] It should be noted that the porosity of the oxide layer 1 is maintained during the first heat treatment, thereby preserving the quality the connection was particularly good.

[0128] Furthermore, before the substrates 21 and 22 are combined, they are treated with a mixture of ozone and a A purified composition of the RCA (Radio Corporation of America) type, known to those skilled in the art.

[0129] Then a second heat treatment, which is a compression heat treatment, is carried out at a temperature between 100 and 1200°C over a period of time between a few minutes and a few hours, preferably at a temperature of 1100°C for 2 hours, in a non- oxidizing gas or a mixture of inert gases is applied. The resulting inert atmosphere consists of the same properties as before. for example, from argon (Ar), nitrogen (N2) or xenon (Xe) or from a mixture of at least two of these inert gases.

[0130] During this second heat treatment The buried oxide layer 20 is compacted, and any defects initially present in the surface layer of the substrate were eliminated. eliminated. Furthermore, this second heat treatment leads to the strengthening of the substrate-to-substrate interfaces.

[0131] Finally, it should be clarified that the examples listed above are merely special representations which in no way represent the Limiting the possible applications of the invention. Summary

[0132] A method is provided for producing a substrate comprising a buried oxide layer (1) for the production electronic components or the like, which includes at least one step for depositing an oxide layer (1) or nitride layer on a so-called donor substrate (2 ) and / or an acceptor substrate as well as a step of establishing contact between the donor substrate and the acceptor substrate (9) comprising the process comprising at least a first heat treatment of the oxide layer (1) or nitride layer which is on the donor substrate (2 ) and / or the acceptor substrate is deposited before connecting the donor substrate (2 ) with the acceptor substrate (9 ) as well as a second heat treatment of the substrate, which consists of the acceptor substrate (9), the oxide layer (1), and the entire donor substrate. (2) or a part thereof, at a temperature that is the same as that applied during the first heat treatment temperature or higher than this.

[0133] A substrate is created which comprises at least one oxide or nitride layer (1) that is deposited on a donor substrate (2) and / or acceptor substrate (9) is deposited, wherein the oxide or nitride layer (1) is degassed and has a refractive index that is less than the Refractive index of an oxide or nitride layer of the same composition formed by thermal growth. QUOTES INCLUDED IN THE DESCRIPTION

[0134] This list of documents cited by the applicant was generated automatically and is solely for the better information of the Readers' contributions were included. The list is not part of the German patent or utility model application. The DPMA assumes no liability whatsoever. for any errors or omissions. Cited patent literature

[0135] - WO 2006 / 029651

[0014] Cited non-patent literature

[0136] - “Silicon-On-Insulator Technology: Materials to VLSI” by Jean-Pierre Colinge, 2nd edition, published by Kluwer Academic Publishers, pages 50 and 51

[0012] - “Silicon-On-Insulator Technology: Materials to VLSI” by Jean-Pierre Colinge, 2nd edition, published by Kluwer Academic Publishers, pages 50 and 51

[0051] - “Silicon-On-Insulator Technology; Materials to VLSI” by Jean- Pierre Colinge, 2nd edition, published by Kluwer Academic Publishers, pages 50 and 51

[0081] - ”Silicon-On-Insulator Technology: Materials VLSI by Jean-Pierre Colinge, 2nd edition, published by Kluwer Academic Publishers, pages 50 and 51

[0100] - “Silicon-On-Insulator Technology: Materials to VLSI” by Jean-Pierre Colinge, 2nd edition, published by Kluwer Academic Publishers, pages 50 and 51

[0113]

Claims

[1] Method for producing a substrate comprising a buried oxide layer (1 , 10 ) for the production of electronic components or such a step, which at least one step towards the deposition of an oxide layer (1 , 10 , 20 ) or a nitride layer on a donor substrate (2 , 11 ) , 21 ) and / or an acceptor substrate as well as a step of establishing contact between the donor substrate and the acceptor substrate (9 , 14 , 22) comprises, characterized in that it comprises at least: a first heat treatment of the oxide layer (1 , 10 , 20 ) or nitride layer that is on the donor substrate (2 , 11 , 21 ) and / or the acceptor- substrate (9 , 14 , 22 ) is deposited, prior to connecting the donor substrate (2 , 11 , 21 ) with the acceptor substrate (9 , 14 , 22 ) as well as a second heat treatment of the substrate, which consists of the acceptor substrate (9 , 14 , 22 ), the oxide layer (1 , 10 , 20 ) and the entire donor substrate (2 , 11 , 21 ) or a part thereof, at a temperature that is the same as that during the first heat treatment The applied temperature is higher than or greater than this. [2] Method according to claim 1, characterized in that the second heat treatment is a compression heat treatment. [3] Method according to claims 1 and 2, characterized in that the first heat treatment consists of maintaining a temperature of 600 to 1000°C for a period of several minutes to several hours in a non-oxidizing inert gas or a mixture of is used with inert gases. [4] Method according to any one of claims 1 to 3, characterized in that the first heat treatment consists of applying a temperature is applied at 800°C for 2 to 4 hours. [5] Method according to any one of claims 1 to 4, characterized in that the second heat treatment consists of applying a temperature from 1000 to 1200°C over a period of a few minutes to a few hours in a non-oxidizing inert gas or a mixture is used from inert gases. [6] Method according to any one of claims 3 to 5, characterized in that the inert gas or the inert gas used in the inert atmosphere is A mixture of inert gases is selected from the following list: Argon (Ar), nitrogen (N2) and xenon (Xe). [7] Method according to any one of claims 1 to 6, characterized in that the oxide precursor is tetraethyl orthosilicate (TEOS). [8] Method according to any one of claims 1 to 6, characterized in that the silicon nitride precursors are dichlorosilane and ammonia. [9] Method according to any one of claims 1 to 8, characterized in that the donor substrate (2 ) consists of a multilayer substrate consists. [10] Method according to claim 9, characterized in that the donor substrate (2 ) is a silicon support substrate (3 ), a silicon- germanium (SiGe) layer (4 ) of increasing composition, a relaxed SiGe layer (5 ) and a layer (6 ) of stretched silicon is formed. [11] Method according to any one of claims 1 to 8, characterized in that the donor substrate (11) and / or the acceptor substrate (9, 14) , 22 ) consists of a silicon substrate with (100)-, (110)- or (111)-crystal orientation. [12] Method according to any one of claims 1 to 11, characterized in that it includes a step of peeling off a wear layer (6, 10) from including the donor substrate (2 , 11 ). [13] Method according to claim 12, characterized in that the step of removing the wear layer (6 , 10 ) is performed by at least the sequence the following steps are carried out: Implantation of ions or gaseous elements from the top of the oxide layer (1, 10) deposited on the donor substrate (2, 11) to to form a buried weakness zone (8, 13) in the donor substrate (2, 11); and then Splitting in the weak zone (8 , 13 ), causing the detachment of the surface layer (6 , 11 ). [14] Method according to claim 13, characterized in that the step of implanting ions or gaseous elements according to the The first heat treatment is carried out, and the splitting step in the weak zone is carried out before the second heat treatment. [15] Method according to claims 10 and 13, characterized in that the parameters of the implantation of elements are selected such that that a weak zone (8 ) is formed in the relaxed SiGe layer (5 ) of the multilayer donor substrate (2 ). [16] Method according to any one of claims 1 to 15, characterized in that it includes a step of preparing the surfaces of the substrates (2, 11, 21; 9, 14, 22) prior to the step of establishing contact between the acceptor substrate (9, 14, 21) and the donor substrate (2, 11 , 21 ) deposited oxide layer (1 , 10 , 20 ) or nitride layer. [17] Substrate comprising at least one oxide or nitride layer (1 ) deposited on a donor substrate (2 ) and / or an acceptor substrate (9 ) ) is deposited, characterized in that the oxide or nitride layer (1 ) is degassed and has a refractive index that is less than the Refractive index of an oxide or nitride layer of the same composition formed by thermal growth. [18] Substrate according to claim 17, characterized in that the refractive index of the degassed oxide or nitride layer (1 ) is between 1.435 and 1.455 for a laser wavelength of 633 nm.

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