RU2368034C1 - Method for manufacturing of silicon-on-insulator structure - Google Patents

Abstract

FIELD: physics, conductors.

SUBSTANCE: invention is related to semiconductor technology and may be used to manufacture device structures. In method for production of silicon-on-insulator structure, insulating layer is generated on substrate surface, and ions of weakly soluble and easily segregating admixture of reactive gases are implanted in it. Conditions of implantation provide for concentration of introduced admixture, which exceeds solubility limit and which, in process of annealing, results in generation of endotaxial layer of dielectric, but insufficient for ion synthesis of precipitates. In donor substrate ion implantation is used to create weakened zone, which extracts layer transferred to insulating layer of substrate. Then chemical treatment of substrate and donor substrate is carried out, and they are connected by insulating layer and layer transferred to substrate, intertwined and stratified in weakened zone with generation of cut-off surface layer on substrate. Further high-temperature treatment is used to segregate implanted admixture to its border of interface with cut-off surface layer, and intermediate insulating layer is grown on specified border.

EFFECT: higher quality of structures and expansion of method application sphere.

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Description

The invention relates to semiconductor technology and can be used to create device structures, in particular silicon-on-insulator (SOI) structures, in the production of modern ultra-large integrated circuits (VLSI) and other products of micro- and nanoelectronics.

A known method of manufacturing a silicon structure on an insulator (US patent No. 5468657 for the invention, IPC: 6 H01L 21/762), which consists in the fact that in the area of the semiconductor substrate, designed to create an insulating layer, form a buried dielectric layer; implantation of nitrogen ions into the substrate, forming a distribution of nitrogen ions centered at the same depth as the region of the insulating layer; conduct thermal treatment of the substrate, causing the migration of nitrogen ions to the boundaries of the buried dielectric layer with the upper and lower regions of the semiconductor of the substrate, thereby passivating at these boundaries. In this case, the formation of a buried dielectric layer is carried out by implantation of oxygen ions in a semiconductor substrate and annealing, forming a buried oxide layer, the implantation of nitrogen ions in the substrate is carried out before or after implantation of oxygen ions or simultaneously, the distribution center of both one and the other implanted ions is located on the same depth of the substrate, subsequent heat treatment of the substrate, causing the migration of nitrogen ions, is carried out simultaneously with annealing, forming a fence enny oxide layer; or the implantation of nitrogen ions into the substrate is carried out after the implantation of oxygen ions and subsequent annealing immediately after it, forming a buried oxide layer, the distribution center of the same and other implanted ions being located at the same depth of the substrate. When implanting nitrogen ions, doses of 1 × 10 ¹¹ ÷ 1 × 10 ¹³ cm ^{-2 are used} . Silicon oxide is formed as a buried dielectric layer by implantation of oxygen ions through the working surface of the substrate, leading to the formation of an oxygen ion distribution centered at the depth of implantation near the working surface, with a dose of 1 × 10 ¹⁷ ÷ 3 × 10 ¹⁸ cm ^-2 and an energy of 30 keV up to 120 keV, provided that the dose of implantable nitrogen ions is the above value, and their energy is equal to the energy of oxygen ions or less by an amount amounting to 25% of the energy of oxygen ions. Heat treatment of the substrate, causing the migration of nitrogen ions to the boundaries of the buried dielectric layer with the upper and lower regions of the semiconductor of the substrate, thereby passivating at the indicated boundaries, is carried out at a temperature of 700 ÷ 1000 ° C for 10 ÷ 30 minutes.

The disadvantages of the technical solution include the low quality of the resulting instrument structures, the narrow scope of the method, in particular, the inability to use the method when creating high-speed VLSI. These disadvantages are due to the following reasons.

First, the formation of a silicon structure on the insulator of a buried dielectric layer by means of implantation of O ⁺ ions into a single-crystal silicon substrate using the indicated doses to obtain a structure. This technological step of the method causes the generation of radiation defects and amorphization of the implanted layer, and, as a result, determines the low quality of the resulting structures. Subsequent high-temperature annealing (thermal processing of the substrate) of the broken silicon layer causes the generation of dislocation loops both in the silicon layer lying below the implanted region and in the silicon layer lying above it, which also negatively affects the quality of the structures. Dislocation loops are stable up to temperatures close to the melting temperature of silicon, and negatively affect the electrophysical properties of devices formed on the basis of the created structures.

Secondly, by the formation of a buried dielectric layer through implantation, which allows one to obtain the thickness of the insulating layer in a narrow range of values - 100–200 nm.

Thirdly, using the indicated values of the ion energy, oxygen, which imposes restrictions on the thickness of the upper cut-off silicon layer. On the one hand, this thickness is limited by the straggling of the implanted ions, and on the other hand, by the maximum achievable ion energy values. This circumstance significantly narrows the scope of the use of the method both for creating structures with subnanometer layer thicknesses and for creating thick insulating and isolated (cut off) layers.

Fourth, the presence of oxygen-containing precipitates at the boundaries of the insulating layer with the upper and lower silicon layers and the nonplanarity of these interfaces, which reduces the quality of structures and has a negative effect on the electrophysical properties of devices. During the formation of a buried dielectric layer by implantation of oxygen ions, a Gaussian-like distribution in the substrate takes place, which does not ensure uniform formation of the insulating layer during high-temperature annealing (thermal treatment of the substrate), as a result of which precipitates form. Measures that eliminate their negative impact in the method are absent. The dissolution of oxygen-containing precipitates requires the use of prolonged high-temperature annealing at temperatures close to the melting temperature of silicon.

Fifth, by implanting N ⁺ ions into the central part of the buried dielectric layer in order to passivate the interface of the insulating layer with the upper and lower silicon layers during subsequent annealing, which causes the formation of implantation defects in it, which cause structural heterogeneity of the silicon oxide layer and the formation of traps charge. Deterioration of the uniformity of the insulating layer and the accumulation of charge traps in it negatively affect the electrophysical properties of devices created on the basis of structures manufactured by this method.

As the closest technical solution to the claimed method, a method of manufacturing a silicon structure on an insulator (US patent No. 7169683 for invention, IPC: 8 H01L 21/48), which consists in the fact that an insulating layer is formed on the surface of the semiconductor substrate on the surface of the semiconductor substrate - donor form a protective layer (intermediate insulating layer) of a chemically resistant material for chemical protection of the insulating layer; after which the substrate and the donor substrate are spliced, connecting the insulating and protective layers; and then carry out the transfer of a layer of semiconductor material from the donor substrate to the substrate, forming on it a severed surface layer of the semiconductor. In the method, the transfer of the semiconductor material layer is carried out by preliminary, prior to splicing, the creation of a weakened zone in the donor substrate, which separates the semiconductor material layer transferred to the substrate located under the protective layer on the donor substrate, and subsequently, by splicing, separating the semiconductor material layer from the donor substrate with the formation of a cut off surface layer of the semiconductor on the substrate. The creation of a weakened zone in the donor substrate is carried out by implanting atoms into the donor substrate to a predetermined depth or by forming a porous layer. Silicon dioxide is used as the insulating layer, the layer of which is obtained by oxidizing the substrate. As the material of the protective layer, a dielectric is used, namely silicon nitride or oxynitride deposited on the donor substrate. The method uses a semiconductor substrate and a silicon donor substrate.

The disadvantages of the closest technical solution include the low quality of the resulting instrument structures, the narrow scope of the method, in particular the inability to use the method when creating high-speed VLSI. The low quality of the interface between the protective layer of silicon nitride and the cut off surface layer of silicon, as well as between the protective layer of silicon nitride and the insulating layer of silicon dioxide of the resulting multilayer structures, limits the use of this method in the technology of creating VLSI and nanotechnology. These disadvantages are due to the following reasons.

Firstly, by creating a protective layer of Si ₃ N ₄ or SiON by the method of deposition on a donor substrate, which does not allow the formation of an atomically smooth interface between the protective layer and the cut off surface silicon layer. In this regard, the interface between these layers is characterized by a high density of positive charge, the presence of which leads to the degradation of devices created on the basis of structures formed by the described method (P. Patruno, M. Kostrzewa, K. Landry, W. Xiong, CRCleavelin, CH .Hsu, M.Ma, JP.Colinge. "Study of fin profiles and MuGFETs built on SOI wafers with nitride-oxide buried layers (NOx-BL) as the buried insulator layer", IEEE Intern. SOI Conf. Proc., P .51, (2007)).

Secondly, to connect the layers of silicon nitride / silicon oxynitride and silicon dioxide, the presence of a broken or porous layer is required, resulting in an imperfect interface between the layers of the connected layers of the dielectric, which is characterized by an increased density of microvoids and centers of accumulation of space charge. This circumstance helps to reduce the breakdown characteristics of the dielectric, has a negative impact on the operation of devices created on the basis of structures formed by this method, and limits its use in micro- and nanoelectronics.

Thirdly, the roughness of the interface between the dielectric layers, as well as between the dielectric layer and the severed surface layer of the semiconductor. In this technical solution, the roughness can reach several nanometers, which leads to the restriction of the use of this method for the manufacture of structures for the creation of devices with a reduced dimension (single-electron and quantum-size devices), for which high demands are placed on the perfection of interfaces.

The technical result of the invention is to improve the quality of the structures of silicon on the insulator, expanding the technological scope of the method.

The technical result is achieved by the fact that in the method of manufacturing the silicon structure on the insulator, which consists in the following sequence of steps: the insulating layer is formed on the surface of the substrate, the substrate and the semiconductor donor substrate are spliced and the layer of semiconductor material is transferred from the donor substrate to the substrate with the formation of the cut-off surface layer of the semiconductor on the substrate, and the transfer of a layer of semiconductor material is carried out by preliminary iem, creating a substrate-donor weakened zone effusing layer of semiconductor material carried on the substrate; in the indicated stages, the insulating layer is formed amorphous, after the formation of the amorphous insulating layer, ions of weakly soluble and easily segregating impurities of reactive gases are implanted under the implantation conditions, which provide an incorporated impurity concentration that exceeds the theoretically possible solubility limit and leads to the formation of an endotaxial layer during subsequent high-temperature processing dielectric with a thickness of at least one monolayer, but insufficient for ionic synthesis of precipitates In the morning of the implantation area, before the splicing, the substrate and the donor substrate are connected by an amorphous insulating layer and a semiconductor material layer transferred to the substrate highlighted by a weakened zone, after the transfer is carried out and the semiconductor surface layer is cut off, the high-temperature treatment is carried out under conditions ensuring segregation of the implanted into the amorphous insulating impurity layer to its interface with the cut-off surface layer of the semiconductor and endotaxial growth at the specified boundary of the intermediate insulating layer with the formation of compounds of the implanted impurity.

In the method, silicon wafers are used as the substrate and the donor substrate.

In the method, the creation of a weakened zone in the donor substrate that separates a layer of semiconductor material transferred to the substrate is carried out by implantation of hydrogen into the donor substrate, and before the hydrogen implantation, a protective layer of silicon oxide is grown through which the implantation is carried out and which after implantation is removed.

In the method, before the substrate and the donor substrate are joined by an amorphous insulating layer and a semiconductor material layer transferred onto the substrate, respectively, the weakened zone, their surfaces to be joined are subjected to a treatment that fuses the substrate and the donor substrate, including cleaning and hydrophilization of the surfaces, followed by washing with an ultrapure deionized jet water, drying and removal of excess physically adsorbed substances from surfaces, after connecting the substrate and the donor substrate are indicated with their surfaces, they are simultaneously spliced and delaminated over the weakened area of the donor substrate with the transfer of a layer of semiconductor material onto the substrate, and drying and removal of excess physically adsorbed substances from the surfaces, connection of the substrate and the donor substrate, and splicing and delamination with transfer are carried out at a temperature ranging from 80 up to 450 ° С, with duration of procedures from 0.1 to 100 hours, in a chamber with a vacuum of 10 ¹ ÷ 10 ³ Pa or in combination with the use of a dry atmosphere.

In the method, implantation into a hydrogen donor substrate is carried out using the energy of hydrogen ions 20 ÷ 200 keV and a dose of 2 × 10 ¹⁶ ÷ 1 × 10 ¹⁷ cm ^-2 .

The method implies implanting into the amorphous insulating layer of ions of a poorly soluble and easily segregating impurity of reactive gases under implantation conditions that provide a concentration of embedded impurity that exceeds the theoretically possible solubility limit and results in the formation of an endotaxial dielectric layer with a thickness of at least one monolayer, but insufficient for ionic synthesis of precipitates within the implantation region, such as the dose of ions 1 × 10 ¹⁵ ÷ 1 × 10 ¹⁶ cm ^-2 and energy 20 ÷ 80 keV, at in this case, nitrogen is used as an impurity, and a layer of SiO ₂ as an amorphous insulating layer.

In the method, a high-temperature treatment is carried out under conditions ensuring segregation of the impurity implanted in the amorphous insulating layer to its interface with the semiconductor surface layer cut off and endotaxial growth at the indicated boundary of the intermediate insulating layer with the formation of compounds with an implanted impurity, such as a temperature of 1000 ÷ 1200 ° C and duration 0.1 ÷ 1 hour, and silicon nitride or oxynitride is formed as compounds with an implanted impurity.

The invention is illustrated by the following description and the accompanying figures. Figure 1 schematically shows the main stages of the fabrication of a silicon structure on an insulator: a) the creation of a weakened zone in the donor substrate, which releases the clipped surface layer of the semiconductor material by implantation of hydrogen into the donor substrate, b) implantation of ions in the amorphous insulating layer is slightly soluble and easily segregating impurities of reactive gases, c) drying and removal of excess physically adsorbed substances from surfaces, joining of a substrate and a donor substrate, splicing and delamination with transfer from cross-sectional surface layer of semiconductor material on a substrate in a vacuum chamber or inert atmosphere, d) high-temperature treatment under conditions that ensure segregation of impurities implanted in the amorphous insulating layer to its interface with the severed surface layer of the semiconductor material and endotaxial growth at the specified boundary of the intermediate insulating layer due to interactions of lattice atoms with an implanted impurity; where 1 is a semiconductor donor substrate, 2 is a layer of semiconductor material transferred to a substrate isolated in the donor substrate by a weakened zone obtained by hydrogen implantation, 3 is a substrate, 4 is an amorphous insulating layer, 5 is the depth of implanted reactive gas ions, 6 - cut off surface layer of the semiconductor; 7 - intermediate insulating layer containing compounds with an implanted impurity. Figure 2 shows high-resolution electron microscopic images of SOI structures containing a silicon substrate, an amorphous SiO ₂ insulating layer with a thickness of 300 nm, a cut-off surface layer of silicon with a thickness of 600 nm, obtained after high-temperature treatment in an atmosphere of N ₂ for 30 minutes at a temperature of 1100 ° C: a) in case of implantation into an amorphous insulating layer of ions

N ⁺ with an energy of 30 keV and a dose of 1 × 10 ¹⁵ cm ^-2 ; b) in the case of implantation into the amorphous insulating layer of N ⁺ ions with an energy of 30 keV and a dose of 6 × 10 ¹⁵ cm ^-2 . Figure 3 shows the capacitance-voltage characteristics of SOI structures with an amorphous insulating layer of SiO ₂ subjected to implantation of N ⁺ ions with a dose of 6 × 10 ¹⁵ cm ^-2 , measured before and after irradiation with γ-quanta: a) at a dose of γ-ray irradiation 10 ⁵ rad, b) at a dose of irradiation with γ-quanta of 3 × 10 ⁵ rad, c) at a dose of irradiation with γ-quanta of 1 × 10 ⁶ rad, where 8 are the characteristics measured before irradiation with γ-quanta, 9 are the characteristics measured after γ-ray irradiation. Figure 4 shows the accumulation of the charge corresponding to the effective charge in the volume of the dielectric and the surface charge at the splicing boundary for fabricated SOI structures, depending on the dose of γ-rays, where 10 is the dependence in case of implantation of nitrogen ions in the amorphous insulating layer with a dose of 1 × 10 ¹⁵ cm ^-2 ; 11 - dependence in the case of implantation into the amorphous insulating layer of nitrogen ions with a dose of 3 × 10 ¹⁵ cm ^-2 ; 12 - dependence in the case of implantation into the amorphous insulating layer of nitrogen ions with a dose of 6 × 10 ¹⁵ cm ^-2 .

In the proposed method, the creation of a silicon structure on an insulator using ion implantation and direct transfer is based on physical laws that determine the transfer processes of semiconductor layers, the segregation process, and the formation of a new insulating phase of implanted poorly soluble impurities of reactive gases at the interface. To confirm the validity of physical concepts, experimental data are presented.

The processes of transferring layers of a semiconductor material, including low-temperature splicing of a substrate (3) and a semiconductor donor substrate (1) (Figure 1) with simultaneous transfer of a layer (2) of semiconductor material, use the difference in surface energies of pairs of hydrophilic and hydrophobic surfaces in different temperature ranges. In the patented technical solution (RF patent No. 2217842 for the invention “A method for manufacturing a silicon-on-insulator structure” by V.P. Popov and I.E. Tyschenko), this feature was the basis for creating Si / SiO ₂ / Si structures. Depending on the purity of the fused surfaces of the substrate (3) and the donor substrate (1), this difference in surface energies can reach several orders of magnitude. The first step in creating SOI structures should be considered as the process of joining hydrophilic surfaces (including the fusion of silicon wafers) and rupture of hydrophobic surfaces (hydrogen-induced transfer of a thin layer of semiconductor material with the formation of a cut-off surface layer of the semiconductor). In this case, the first problem to be solved (Fig. 1, stages a) -c)) in the proposed method for manufacturing silicon structures on an insulator is the formation on a substrate (3) containing an amorphous insulating layer (4) on the working surface, of a cut off surface layer (6) a semiconductor, which is carried out by creating a weakened zone in the donor substrate (1) that releases a layer (2) of semiconductor material transferred to the substrate (3) by implanting hydrogen (the so-called hydrogen-induced transfer with semiconductors oic donor substrate).

In any case, the parameters that determine the magnitude of surface energy are temperature and the high structural quality of the surfaces. In this regard, one of the main requirements necessary to achieve a complete (100%) hydrophilic connection of the substrate (3) and the semiconductor donor substrate (1) is to ensure the maximum possible cleanliness of the surfaces of the fused silicon wafers, the absence of physically adsorbed impurities on the initial surfaces and subsequent direct hydrophilization of the surfaces of the substrate (3) and the donor substrate (1). After hydrophilization, the silicon wafers should be dried and physically adsorbed substances removed from their surface, for which they are placed in a centrifuge of a vacuum chamber and heated there to the temperatures necessary for this. Then they are paired.

Internal hydrophobic surfaces in adjacent atomic planes, which are parallel to the surface of the semiconductor donor substrate (1), are preliminarily formed in the semiconductor layer undergoing hydrogen implantation, which results in the creation of a weakened zone in the donor substrate (1) that releases the layer (2) semiconductor material transferred onto a substrate (3). The formation of such surfaces occurs by the formation of bonds in the XHHX layer after implantation as a result of hydrogen capture on the stretched and weakened XX bonds of the semiconductor matrix perpendicular to the surface. In order to ensure the creation of two hydrophobic (100) planes with a full (100%) XHHX bond coating at implantation at a depth of the average projective range of ions R _p , which leads to the formation of a severed surface layer (6) of the semiconductor on the substrate (3), ion doses are required H ⁺ , H ₂ ⁺ 2 × 10 ¹⁶ ÷ 1 × 10 ¹⁷ cm ^-2 at their energies from 20 to 200 keV.

The second step is the implementation of the process of creating an additional, intermediate (between the cut off surface layer of the semiconductor and insulating layer), insulating layer (7), due to which the quality of the structures produced by the proposed method is increased and the scope of the method is expanded. The second problem to be solved is the formation of an intermediate insulating layer (7) (Figure 1, stage b) -d)). The implementation of the second step is based on the use of the properties of gas reactive impurities to have low solubility in the substance and extremely low ability to form bonds with atoms of the matrix based on silicon. Atoms of reactive impurities implanted in a solid-state matrix (which is an amorphous insulating layer (4) on a substrate (3)) have the ability to form gas molecules with a small radius, which, without being bound to the matrix lattice, are characterized by a sufficiently large diffusion coefficient. In turn, gas molecules easily interact with defects inside the implanted matrix or with existing competing sinks, such as the real crystal surface or internal interfaces. This means that structural disturbances, in particular internal interfaces, can be the center of accumulation of reactive impurities and the subsequent formation of a new phase with the participation of the implanted impurity and the material of the implanted medium during subsequent high-temperature treatments. The described properties and abilities are possessed by an admixture of nitrogen introduced by ion implantation into the amorphous insulating layer (4) of SiO ₂ located on the substrate (3) of Si. In this case, nitrogen, entering into a chemical reaction with silicon, can crystallize at relatively low temperatures with the formation of α- and β-modifications of Si ₃ N ₄ .

The determining parameters when creating an intermediate insulating layer (7) (see Figure 1, stage d)) are the concentration of the embedded impurity and the temperature of the high-temperature treatment. The concentration of nitrogen atoms in SiO ₂ should ensure the formation of a silicon nitride or oxynitride layer (7) of a silicon nitride or oxynitride layer at least one monolayer at the interface between the SOI structure and subsequent to implantation annealing (high-temperature treatment), but not sufficient for ion synthesis of precipitates at a depth of (5) corresponding to the maximum distribution of embedded nitrogen ions. This condition is satisfied when using energy from 30 to 80 keV and a dose of nitrogen ions of 1 × 10 ¹⁵ ÷ 1 × 10 ¹⁶ cm ^-2 . The temperature range in which the conditions for maximum segregation of nitrogen atoms from the implanted volume of SiO ₂ to the Si / SiO ₂ interface are realized is usually 1000-1200 ° C (WJMJ Josquin, “The application of nitrogen ion implantation in silicon technology", Nucl. Instrum . Meth., 209/210, (2003), pp581-587; E.Zhang, W.Yi, J. Chen, Z. Zhang, X. Wang, "Research on the effect of nitrogen implantation dose on the structure of separation by implantation of oxygen and nitrogen ”. Smart. Mater. Struct., V.14, (2005), ppN42-N45) and is determined both by the distance from the maximum distribution of the implanted atoms to the Si / SiO ₂ boundary and the concentration of effective sinks for nitrogen atoms in the exposed The presence of a second single-crystal medium (in this case, a cut off surface layer (6) of silicon) with a low solubility coefficient of interstitial atoms adjacent to the amorphous insulating layer (4) ensures the accumulation of impurities at the interface with the amorphous insulating layer (4), as well as epitaxial crystallization with the formation of an intermediate insulating layer (7) at the indicated interface during high-temperature annealing. Therefore, when forming SOI structures with an intermediate insulating layer (7) of silicon nitride, it is necessary to take into account the ability of silicon nitride to crystallize during high-temperature annealing (G. Kachurin, I. E. Tyschenko. “Ion synthesis of buried dielectric layers for silicon-on-insulator structures ", Microelectronics, t.23, v.6, (1994), pp. 3-12) at specific temperatures. Subsequent high-temperature treatment at temperatures of 1000 ÷ 1200 ° C allows both segregation of the embedded nitrogen impurity at the interface and the formation of a new crystalline phase.

The photographs shown in FIG. 2 show the formation of a new phase, such as silicon nitride or oxynitride, at the interface of the cut off silicon surface layer and the amorphous insulating layer (SiO ₂ ). Depending on the introduced dose of ions at a fixed temperature and annealing time, respectively, 1100 ° С and 30 minutes, the thickness of the intermediate insulating layer for different doses of the introduced impurity is different. In the case of Fig. 2a), at a dose of N ⁺ ions with an energy of 30 keV equal to 1 × 10 ¹⁵ cm ^-2 , the layer thickness is insignificant (see the middle part of the photograph). With a six-fold increase in the dose of ions (see Fig. 2b), the intermediate layer (the brightest middle part of the light section), which is continuous and crystalline, is clearly visible in the photograph.

Figure 3 and Figure 4 demonstrate the quality of manufactured by the proposed method structures in relation to their electrophysical properties.

Figure 3 presents the capacitance-voltage characteristics, which make it possible to judge the electrophysical properties of the internal interfaces of the SOI structure and the structure as a whole: the curves located on the right-hand sides a), b) and c) of Figure 3 relate to the interfaces of the structure part, consisting of an insulating layer of SiO ₂ , an intermediate insulating layer of Si ₃ N ₄ and a single-crystal cut-off surface layer of Si; the curves located in the left-hand sides of a), b) and c) of FIG. 3 are related to the interface between the SiO ₂ insulating layer and the Si substrate. Curves (8) were measured before irradiation with γ-quanta, curves (9) - after irradiation with γ-quanta. Insignificant voltage shifts of the flat zones of the capacitance-voltage characteristics (8) and (9) in the region of positive voltages with increasing radiation dose by γ-quanta indicate a high stability of the state of the interface and, therefore, their high quality (low charge density). Achieving a high quality of interface in this part of the SOI structure, that is, from the side of the cut off surface layer of Si, is of paramount importance, since this part of the structure is intended for the manufacture of devices.

Figure 4 shows the accumulation of a charge corresponding to the effective charge in the volume of the dielectric and the surface charge at the splicing boundary of the generated SOI structures, depending on the dose of γ-rays, at various doses of nitrogen ions implanted into the amorphous insulating layer used in the manufacture SOI structures: curve (10) in the case of implantation of nitrogen ions in a amorphous insulating layer with a dose of 1 × 10 ¹⁵ cm ^-2 ; curve (11) in the case of implantation into the amorphous insulating layer of nitrogen ions with a dose of 3 × 10 ¹⁵ cm ^-2 ; curve (12) in the case of implantation of nitrogen ions into a amorphous insulating layer with a dose of 6 × 10 ¹⁵ cm ^-7 . It can be seen that the charge density does not exceed 10 ¹¹ cm ^-2 , which indicates the high quality of the manufactured structures.

Thus, in the proposed method, combinations of different media are used that are adjacent to each other, in which the introduced medium, which are implanted ions of reactive gases, has low solubility. This circumstance ensures the accumulation of the implanted reactive impurity on defects inside the implanted medium or at the interface between two media, into one of which the medium with low solubility was introduced. The presence of media corresponding to the low solubility coefficient of the introduced impurity ensures its accumulation at the interface, as well as the formation of a new phase under high temperature influences.

Based on the stated physical concepts, the manufacture of the SOI structure with the achievement of a technical result is ensured by the implementation of the following stages (see Figure 1).

1. The formation on the donor substrate of a layer of semiconductor material transferred to the substrate. Hydrogen implantation is carried out in a donor semiconductor substrate (1). This creates a weakened zone in the donor substrate, releasing a layer of semiconductor material transferred to the substrate (2). In this case, a silicon wafer is used as a donor substrate (1). Before implantation, a protective layer of silicon oxide can be grown on it, through which implantation is carried out and which is removed after implantation. For implantation using hydrogen ions with an energy value of 20 ÷ 200 keV and doses of 2 × 10 ¹⁶ ÷ 1 × 10 ¹⁷ cm ^-2 (stage a) Figure 1.

2. Implantation into the amorphous insulating layer of the substrate of ions of poorly soluble and easily segregating impurities of reactive gases. An amorphous insulating layer (4) is formed on the surface of the substrate (3). After the formation of an amorphous insulating layer (4), ions of a poorly soluble and easily segregating impurity of reactive gases are implanted under it under implantation conditions that ensure the concentration of the incorporated impurity that exceeds the theoretically possible solubility limit and leads to the formation of an endotaxial dielectric layer with a thickness of at least one monolayer, but insufficient for ionic synthesis of precipitates within the implantation region (stage b) of Figure 1). The implantation of ions is carried out to a depth of (5) (the depth of the implanted ions of reactive gases). At the same time, a silicon wafer is used as a substrate (3), and an SiO ₂ layer is used as an amorphous insulating layer (4). Implantation conditions: ion dose value 1 × 10 ¹⁵ ÷ 1 × 10 ¹⁶ cm ^-2 ; energy 20 ÷ 80 keV; the introduced admixture is nitrogen.

3. The formation of the cut-off surface layer of the semiconductor on the surface of the amorphous insulating layer of the substrate. The substrate (3) and the donor substrate (1) are connected by an amorphous insulating layer (4) and a semiconductor material layer (2) allocated to the weakened zone transferred onto the substrate, spliced and the layer (2) of the semiconductor material is transferred from the donor substrate (1) on the substrate (3) with the formation of the cut-off surface layer of the semiconductor (6) on the substrate (3). Before connecting the substrate (3) and the donor substrate (1), respectively, with an amorphous insulating layer (4) and a semiconductor material layer (2) highlighted by the weakened zone transferred onto the substrate (3), their joined surfaces are processed. The treatment includes cleaning and hydrophilizing surfaces, subsequent washing with a stream of ultrapure deionized water, drying and removal of excess physically adsorbed substances from the surfaces. After connecting the substrate (3) and the donor substrate (1) with the indicated surfaces, they are simultaneously spliced and layered along the weakened zone of the donor substrate (1) with the transfer of the semiconductor material layer (2) onto the substrate (3) (step c) Figure 1) . Moreover, the drying and removal of excess physically adsorbed substances from the surfaces, the connection of the substrate (3) and the donor substrate (1), splicing and delamination with transfer is carried out with temperature varying from 80 to 450 ° C, with a duration of procedures from 0.1 to 100 hours , in a chamber with a vacuum of 10 ¹ ÷ 10 ³ Pa or in combination with the use of a dry atmosphere.

4. The formation of an intermediate insulating layer. High-temperature treatment is carried out under conditions ensuring segregation of the impurity implanted in the amorphous insulating layer (4) to its interface with the semiconductor surface layer cut off (6) and endotaxial growth at the indicated boundary of the intermediate insulating layer (7) with the formation of implanted impurity compounds and atoms of the initial matrix , namely silicon nitride or oxynitride (step d) of FIG. 1). Processing conditions: temperature 1000 ÷ 1200 ° C; Duration 0.1 ÷ 1 hour.

The main differences in the proposed method from the closest technical solution are the implementation before implanting a layer of a single-crystal semiconductor material from a donor substrate to an implantation substrate in an amorphous insulating layer placed on the substrate and acting as an amorphous matrix, ions of poorly soluble and easily segregating impurities of reactive gases, and also in that the interface between the layers after the transfer is the place of accumulation of the implanted impurity of reactive gases and endotax cial growth intermediate insulating layer. The achievement of the technical result is ensured by the fact that through the implantation of impurity ions involved in the formation of the intermediate insulating layer into the amorphous insulating layer and further segregation of the impurity to the interface of the single crystal severed surface layer of the semiconductor and the amorphous insulating layer, the need to create a disturbed layer between the intermediate insulating and amorphous insulating is eliminated in layers. As a result, the absence of microvoids and high perfection of the interface between the insulating layers is achieved, and the atomically smooth interface between the single-crystal cut-off surface layer of the semiconductor and the intermediate insulating layer is preserved, providing a decrease in the density of built-in charges at this interface and the rate of charge accumulation in the SOI structure during subsequent ionizing impacts.

As information confirming the possibility of implementing the proposed method with the achievement of the specified technical result, we give the following implementation examples.

Example 1

To fabricate the SOI structure, a sequence of steps is carried out: an amorphous insulating layer is formed on the surface of the substrate, after the formation of ions of a poorly soluble and easily segregating impurity of reactive gases, implantation is carried out under implantation conditions that ensure the concentration of the incorporated impurity that exceeds the theoretically possible solubility limit and results in the subsequent high-temperature processing to form an endotaxial dielectric layer at least one monolayer thick, but not residual for ionic synthesis of precipitates within the implantation region; to transfer a layer of semiconductor material, a weakened zone is formed in the donor substrate, which releases a layer of semiconductor material transferred to the substrate; the substrate and the donor semiconductor substrate are spliced and the layer of the semiconductor material is transferred from the donor substrate to the substrate to form a clipped semiconductor surface layer on the substrate; carry out high-temperature processing under conditions that ensure segregation of the impurity implanted in the amorphous insulating layer to its interface with the semiconductor surface layer cut off and endotaxial growth at the specified boundary of the intermediate insulating layer with the formation of implanted impurity compounds.

Silicon wafers are used as the substrate and the donor substrate.

The creation of a weakened zone in the donor substrate, which releases a layer of semiconductor material transferred to the substrate, is carried out by implantation of hydrogen into the donor substrate, while before the implantation of hydrogen, a protective layer of silicon oxide of 50 nm is grown through which the implantation is carried out and which after implantation is removed. Implantation is carried out using hydrogen ion energy of 140 keV and a dose of 2.5 × 10 ¹⁶ cm ^-2 .

When implanting ions of a slightly soluble and easily segregating impurity of reactive gases into an amorphous insulating layer of ions, nitrogen, N ⁺ , is used as an impurity. To implement implantation conditions that ensure the concentration of the introduced impurity that exceeds the theoretically possible solubility limit and leads to the formation of an endotaxial dielectric layer with a thickness of at least one monolayer, but insufficient for ionic synthesis of precipitates within the implantation region, using a dose of ions of 1 × 10 ¹⁵ cm ^-2 and an energy of 20 keV. The impurity is introduced into an amorphous insulating layer — a thermally grown SiO ₂ layer 300 nm thick.

Before connecting the substrate and the donor substrate, respectively, with an amorphous insulating layer and a semiconductor material layer transferred to the substrate, the weakened zone is transferred to the substrate, the surfaces to be joined are subjected to a process that fuses the substrate and the donor substrate, including cleaning and hydrophilization of the surfaces, followed by washing with an ultrapure deionized water jet, drying and removal of excess physically adsorbed substances from surfaces. After the substrate and the donor substrate are joined by the indicated surfaces, they are simultaneously spliced and layered along the weakened area of the donor substrate with the transfer of a layer of semiconductor material onto the substrate. Drying and removal of excess physically adsorbed substances from the surfaces is carried out at 200 ° C for 0.1 hour, the subsequent connection of the substrate and the donor substrate, splicing and delamination with transfer is carried out at 450 ° C for 0.5 hours in a vacuum chamber 10 ³ Pa.

High-temperature treatment under conditions ensuring segregation of the impurity implanted in the amorphous insulating layer to its interface with the severed surface layer of the semiconductor material and endotaxial growth at the indicated boundary of the intermediate insulating layer with the formation of compounds with an implanted impurity is carried out at 1100 ° C for a duration of 0.3 hours in an atmosphere of nitrogen. In this case, silicon nitride is formed with a thickness of the order of one monolayer.

As a result, a SOI structure is produced that is free from dislocation and mismatch defects, containing successively in the direction of the substrate layers: 0.6 μm Si, 1 monolayer Si ₃ N ₄ , 0.30 μm SiO ₂ on the Si substrate.

Example 2

To fabricate the SOI structure, a sequence of steps is carried out: an amorphous insulating layer is formed on the surface of the substrate, after the formation of ions of a poorly soluble and easily segregating impurity of reactive gases, implantation is carried out under implantation conditions that ensure the concentration of the incorporated impurity that exceeds the theoretically possible solubility limit and results in the subsequent high-temperature processing to form an endotaxial dielectric layer at least one monolayer thick, but not residual for ionic synthesis of precipitates within the implantation region; to transfer a layer of semiconductor material, a weakened zone is formed in the donor substrate, which releases a layer of semiconductor material transferred to the substrate; the substrate and the donor semiconductor substrate are spliced and the layer of the semiconductor material is transferred from the donor substrate to the substrate to form a clipped semiconductor surface layer on the substrate; carry out high-temperature processing under conditions that ensure segregation of the impurity implanted in the amorphous insulating layer to its interface with the semiconductor surface layer cut off and endotaxial growth at the specified boundary of the intermediate insulating layer with the formation of implanted impurity compounds.

Silicon wafers are used as the substrate and the donor substrate.

The creation of a weakened zone in the donor substrate, which releases a layer of semiconductor material transferred to the substrate, is carried out by implantation of hydrogen into the donor substrate, while before the implantation of hydrogen, a protective layer of silicon oxide of 50 nm is grown through which the implantation is carried out and which after implantation is removed. Implantation is carried out using hydrogen ion energy of 140 keV and a dose of 2.5 × 10 ¹⁶ cm ^-2 .

When implanting ions of a slightly soluble and easily segregating impurity of reactive gases into an amorphous insulating layer of ions, nitrogen, N ⁺ , is used as an impurity. To implement implantation conditions that ensure an implant concentration that exceeds the theoretically possible solubility limit and leads to the formation of an endotaxial dielectric layer with a thickness of at least one monolayer, but insufficient for ionic synthesis of precipitates within the implantation region, using a dose of 3 × 10 ¹⁵ cm ^-2 and an energy of 30 keV. The impurity is introduced into an amorphous insulating layer — a thermally grown SiO ₂ layer 300 nm thick.

Before connecting the substrate and the donor substrate, respectively, with an amorphous insulating layer and a semiconductor material layer transferred to the substrate, the weakened zone is transferred to the substrate, the surfaces to be joined are subjected to a process that fuses the substrate and the donor substrate, including cleaning and hydrophilization of the surfaces, followed by washing with an ultrapure deionized water jet, drying and removal of excess physically adsorbed substances from surfaces. After the substrate and the donor substrate are joined by the indicated surfaces, they are simultaneously spliced and layered along the weakened area of the donor substrate with the transfer of a layer of semiconductor material onto the substrate. Drying and removal of excess physically adsorbed substances from surfaces is carried out at 200 ° C for 0.1 hour, subsequent connection of the substrate and the donor substrate, splicing and delamination with transfer is carried out at 350 ° C for 1 hour in a chamber with a vacuum of 10 ² Pa .

High-temperature treatment under conditions ensuring segregation of the impurity implanted in the amorphous insulating layer to its interface with the severed surface layer of the semiconductor material and endotaxial growth at the indicated boundary of the intermediate insulating layer with the formation of compounds with an implanted impurity is carried out at 1100 ° C for a duration of 0.4 hours in an inert atmosphere of nitrogen. In this case, silicon nitride is formed with a thickness of the order of 2 monolayers.

As a result, a SOI structure is produced that is free from dislocation and mismatch defects, containing successively in the direction of the substrate layers: 0.6 μm Si, 2 monolayers Si ₃ N ₄ , 0.30 μm SiO ₂ on the Si substrate.

Example 3

To fabricate the SOI structure, a sequence of steps is carried out: an amorphous insulating layer is formed on the surface of the substrate, after the formation of ions of a poorly soluble and easily segregating impurity of reactive gases, implantation is carried out under implantation conditions that ensure the concentration of the incorporated impurity that exceeds the theoretically possible solubility limit and results in the subsequent high-temperature processing to form an endotaxial dielectric layer at least one monolayer thick, but not residual for ionic synthesis of precipitates within the implantation region; to transfer a layer of semiconductor material, a weakened zone is formed in the donor substrate, which releases a layer of semiconductor material transferred to the substrate; the substrate and the donor semiconductor substrate are spliced and the layer of the semiconductor material is transferred from the donor substrate to the substrate to form a clipped semiconductor surface layer on the substrate; subsequent high-temperature treatment is carried out under conditions ensuring segregation of the impurity implanted in the amorphous insulating layer to its interface with the semiconductor surface layer cut off and endotaxial growth at the indicated boundary of the intermediate insulating layer with the formation of implanted impurity compounds.

Silicon wafers are used as the substrate and the donor substrate.

The creation of a weakened zone in the donor substrate, which emits a layer of semiconductor material transferred to the substrate, is carried out by implantation of hydrogen into the donor substrate, and before the implantation of hydrogen, a protective layer of 5 nm silicon oxide is grown through which the implantation is carried out and which after implantation is removed. Implantation is carried out using the energy of hydrogen ions of 20 keV and a dose of 4 × 10 ¹⁶ cm ^-2 .

When implanting ions of a slightly soluble and easily segregating impurity of reactive gases into an amorphous insulating layer of ions, nitrogen, N ⁺ , is used as an impurity. To implement the implantation conditions that ensure the concentration of the introduced impurity that exceeds the theoretically possible solubility limit and leads to the formation of an endotaxial dielectric layer with a thickness of at least one monolayer, but insufficient for ionic synthesis of precipitates within the implantation region, first use a dose of 5 × 10 ions ¹⁵ cm ^-2 and an energy of 30 keV, then a dose of ions of 5 × 10 ¹⁵ cm ^-2 and an energy of 80 keV. The impurity is introduced into an amorphous insulating layer — a thermally grown SiO ₂ layer 300 nm thick.

Before connecting the substrate and the donor substrate, respectively, with an amorphous insulating layer and a semiconductor material layer transferred to the substrate, the weakened zone is transferred to the substrate, the surfaces to be joined are subjected to a process that fuses the substrate and the donor substrate, including cleaning and hydrophilization of the surfaces, followed by washing with an ultrapure deionized water jet, drying and removal of excess physically adsorbed substances from surfaces. After the substrate and the donor substrate are joined by the indicated surfaces, they are simultaneously spliced and layered along the weakened area of the donor substrate with the transfer of a layer of semiconductor material onto the substrate. Drying and removal of excess physically adsorbed substances from the surfaces is carried out at 200 ° C for 0.1 hours under a vacuum of 10 ¹ Pa, subsequent connection of the substrate and the donor substrate, splicing and delamination with transfer is carried out at 200 ° C for 0.15 hours in a chamber with a dry inert atmosphere.

High-temperature treatment under conditions ensuring segregation of an impurity implanted in an amorphous insulating layer to its interface with a cut off surface layer of a semiconductor material and endotaxial growth at the indicated interface of an intermediate insulating layer with the formation of compounds with an implanted impurity is carried out at 1200 ° C for 0.1 hours in an inert atmosphere of nitrogen. In this case, silicon nitride is formed with a thickness of the order of 2 monolayers.

As a result, a SOI structure is produced that is free from dislocation and mismatch defects, containing successively in the direction of the substrate layers: 0.6 μm Si, 2 monolayer Si ₃ N ₄ , 0.30 μm SiO ₂ , 2 monolayer Si ₃ N ₄ per Si substrate.

Example 4

To fabricate the SOI structure, a sequence of steps is carried out: an amorphous insulating layer is formed on the surface of the substrate, after the formation of ions of a poorly soluble and easily segregating impurity of reactive gases, implantation is carried out under implantation conditions that ensure the concentration of the incorporated impurity that exceeds the theoretically possible solubility limit and results in the subsequent high-temperature processing to form an endotaxial dielectric layer at least one monolayer thick, but not residual for ionic synthesis of precipitates within the implantation region; to transfer a layer of semiconductor material, a weakened zone is formed in the donor substrate, which releases a layer of semiconductor material transferred to the substrate; the substrate and the donor semiconductor substrate are spliced and the layer of the semiconductor material is transferred from the donor substrate to the substrate to form a clipped semiconductor surface layer on the substrate; carry out high-temperature processing under conditions that ensure segregation of the impurity implanted in the amorphous insulating layer to its interface with the semiconductor surface layer cut off and endotaxial growth at the specified boundary of the intermediate insulating layer with the formation of implanted impurity compounds.

Silicon wafers are used as the substrate and the donor substrate.

The creation of a weakened zone in the donor substrate, which releases a layer of semiconductor material transferred to the substrate, is carried out by implantation of hydrogen into the donor substrate, while before the implantation of hydrogen, a protective layer of silicon oxide of 50 nm is grown through which the implantation is carried out and which after implantation is removed. Implantation is carried out using 200 keV hydrogen ion energy and a dose of 1 × 10 ¹⁷ cm ^-2 .

When implanting ions of a slightly soluble and easily segregating impurity of reactive gases into an amorphous insulating layer of ions, nitrogen, N ⁺ , is used as an impurity. To implement implantation conditions that ensure the concentration of the incorporated impurity that exceeds the theoretically possible solubility limit and leads to the formation of an endotaxial dielectric layer with a thickness of at least one monolayer, but insufficient for ionic synthesis of precipitates within the implantation region, using a dose of 1 × 10 ¹⁶ cm ^-2 and energy 60 keV. The impurity is introduced into an amorphous insulating layer — a thermally grown SiO ₂ layer 300 nm thick.

Before connecting the substrate and the donor substrate, respectively, with an amorphous insulating layer and a semiconductor material layer transferred to the substrate, the weakened zone is transferred to the substrate, the surfaces to be joined are subjected to processing that fuses the substrate and the donor substrate, including cleaning and hydrophilization of the surfaces, followed by washing with an ultrapure deionized water jet, drying and removal of excess physically adsorbed substances from surfaces. After connecting the substrate and the donor substrate with the indicated surfaces, they are simultaneously spliced and layered along the weakened zone of the donor substrate with the transfer of a layer of semiconductor material onto the substrate. Drying and removal of excess physically adsorbed substances from surfaces is carried out at 200 ° C for 0.1 hour, the subsequent connection of the substrate and the donor substrate, splicing and delamination with transfer is carried out at 350 ° C for 1 hour in a chamber with 10 Pa vacuum.

High-temperature treatment under conditions ensuring segregation of an impurity implanted in an amorphous insulating layer to its interface with a cut off surface layer of a semiconductor material and endotaxial growth at the indicated interface of an intermediate insulating layer with the formation of compounds with an implanted impurity is carried out at 1200 ° C for 0.1 hours in an inert atmosphere of nitrogen. In this case, silicon nitride is formed with a thickness of the order of 2 monolayers.

As a result, a SOI structure is produced that is free from dislocation and mismatch defects, containing successively in the direction of the substrate layers: 0.6 μm Si, 2 monolayer Si ₃ N ₄ , 0.30 μm SiO ₂ , 2 monolayer Si ₃ N ₄ per Si substrate.

Example 5

To fabricate the SOI structure, a sequence of steps is carried out: an amorphous insulating layer is formed on the surface of the substrate, after the formation of ions of a poorly soluble and easily segregating impurity of reactive gases, implantation is carried out under implantation conditions that ensure the concentration of the incorporated impurity that exceeds the theoretically possible solubility limit and results in the subsequent high-temperature processing to form an endotaxial dielectric layer at least one monolayer thick, but not residual for ionic synthesis of precipitates within the implantation region; to transfer a layer of semiconductor material, a weakened zone is formed in the donor substrate, which releases a layer of semiconductor material transferred to the substrate; the substrate and the donor semiconductor substrate are spliced and the layer of the semiconductor material is transferred from the donor substrate to the substrate to form a clipped semiconductor surface layer on the substrate; carry out high-temperature processing under conditions that ensure segregation of the impurity implanted in the amorphous insulating layer to its interface with the semiconductor surface layer cut off and endotaxial growth at the specified boundary of the intermediate insulating layer with the formation of implanted impurity compounds.

Silicon wafers are used as the substrate and the donor substrate.

The creation of a weakened zone in the donor substrate, which releases a layer of semiconductor material transferred to the substrate, is carried out by implantation of hydrogen into the donor substrate, while before the implantation of hydrogen, a protective layer of silicon oxide of 50 nm is grown through which the implantation is carried out and which after implantation is removed. Implantation is carried out using the energy of hydrogen ions of 120 keV and a dose of 2 × 10 ¹⁶ cm ^-2 .

When implanting ions of a slightly soluble and easily segregating impurity of reactive gases into an amorphous insulating layer of ions, nitrogen, N ⁺ , is used as an impurity. To implement implantation conditions that ensure the concentration of the introduced impurity that exceeds the theoretically possible solubility limit and leads to the formation of an endotaxial dielectric layer with a thickness of at least one monolayer, but insufficient for ionic synthesis of precipitates within the implantation region, using a dose of 4 × 10 ¹⁵ cm ^-2 and an energy of 40 keV. The impurity is introduced into an amorphous insulating layer — a thermally grown SiO ₂ layer 300 nm thick.

Before connecting the substrate and the donor substrate, respectively, with an amorphous insulating layer and a semiconductor material layer transferred to the substrate, the weakened zone is transferred to the substrate, the surfaces to be joined are subjected to a process that fuses the substrate and the donor substrate, including cleaning and hydrophilization of the surfaces, followed by washing with an ultrapure deionized water jet, drying and removal of excess physically adsorbed substances from surfaces. After the substrate and the donor substrate are joined by the indicated surfaces, they are simultaneously spliced and layered along the weakened area of the donor substrate with the transfer of a layer of semiconductor material onto the substrate. Drying and removal of excess physically adsorbed substances from the surfaces is carried out at 200 ° C for 0.1 hour, the subsequent connection of the substrate and the donor substrate, splicing and delamination with transfer is carried out at 80 ° C for 100 hours in a chamber with a vacuum of 10 ¹ Pa .

High-temperature treatment under conditions ensuring segregation of an impurity implanted in an amorphous insulating layer to its interface with a severed surface layer of semiconductor material and endotaxial growth at the indicated boundary of the intermediate insulating layer with the formation of compounds with an implanted impurity is carried out at 1000 ° C for 1 hour in an inert nitrogen atmosphere. In this case, silicon nitride is formed with a thickness of the order of 1 monolayer.

As a result, a SOI structure is produced that is free from dislocation and mismatch defects, containing successively in the direction of the substrate layers: 0.6 μm Si, 1 monolayer Si ₃ N ₄ , 0.30 μm SiO ₂ on the Si substrate.

Example 6

To fabricate the SOI structure, a sequence of steps is carried out: an amorphous insulating layer is formed on the surface of the substrate, after the formation of ions of a poorly soluble and easily segregating impurity of reactive gases, implantation is carried out under implantation conditions that ensure the concentration of the incorporated impurity that exceeds the theoretically possible solubility limit and results in the subsequent high-temperature processing to form an endotaxial dielectric layer at least one monolayer thick, but not residual for ionic synthesis of precipitates within the implantation region; to transfer a layer of semiconductor material, a weakened zone is formed in the donor substrate, which releases a layer of semiconductor material transferred to the substrate; the substrate and the donor semiconductor substrate are spliced and the layer of the semiconductor material is transferred from the donor substrate to the substrate to form a clipped semiconductor surface layer on the substrate; carry out high-temperature processing under conditions that ensure segregation of the impurity implanted in the amorphous insulating layer to its interface with the semiconductor surface layer cut off and endotaxial growth at the specified boundary of the intermediate insulating layer with the formation of implanted impurity compounds.

Silicon wafers are used as the substrate and the donor substrate.

The creation of a weakened zone in the donor substrate, which releases a layer of semiconductor material transferred to the substrate, is carried out by implantation of hydrogen into the donor substrate, while before the implantation of hydrogen, a protective layer of silicon oxide of 50 nm is grown through which the implantation is carried out and which after implantation is removed. Implantation is carried out using hydrogen ion energy of 140 keV and a dose of 2.5 × 10 ¹⁶ cm ^-2 .

When implanting ions of a slightly soluble and easily segregating impurity of reactive gases into an amorphous insulating layer of ions, nitrogen, N ⁺ , is used as an impurity. To implement implantation conditions that ensure the concentration of the introduced impurity that exceeds the theoretically possible solubility limit and leads to the formation of an endotaxial dielectric layer with a thickness of at least one monolayer, but insufficient for ionic synthesis of precipitates within the implantation region, using a dose of 4 × 10 ¹⁵ cm ^-2 and an energy of 40 keV. The impurity is introduced into an amorphous insulating layer — a thermally grown SiO ₂ layer 300 nm thick.

Before connecting the substrate and the donor substrate, respectively, with an amorphous insulating layer and a semiconductor material layer transferred to the substrate, the weakened zone is transferred to the substrate, the surfaces to be joined are subjected to a process that fuses the substrate and the donor substrate, including cleaning and hydrophilization of the surfaces, followed by washing with an ultrapure deionized water jet, drying and removal of excess physically adsorbed substances from surfaces. After connecting the substrate and the donor substrate with the indicated surfaces, they are simultaneously spliced and layered along the weakened zone of the donor substrate with the transfer of a layer of semiconductor material onto the substrate. Drying and removal of excess physically adsorbed substances from surfaces is carried out at 200 ° C for 0.1 hour, subsequent connection of the substrate and the donor substrate, splicing and delamination with transfer is carried out at 350 ° C for 1 hour in a chamber with a vacuum of 10 ¹ Pa .

High-temperature treatment under conditions ensuring segregation of an impurity implanted in an amorphous insulating layer to its interface with a severed surface layer of a semiconductor material and endotaxial growth at the indicated boundary of an intermediate insulating layer with the formation of compounds with an implanted impurity is carried out at 1000 ° C for 1 hour in the atmosphere nitrogen. In this case, silicon nitride is formed with a thickness of the order of one monolayer.

As a result, a SOI structure is produced that is free from dislocation and mismatch defects, containing successively in the direction of the substrate layers: 0.6 μm Si, 1 monolayer Si ₃ N ₄ , 0.30 μm SiO ₂ on the Si substrate.

Example 7

To fabricate the SOI structure, a sequence of steps is carried out: an amorphous insulating layer is formed on the surface of the substrate, after the formation of ions of a poorly soluble and easily segregating impurity of reactive gases, implantation is carried out under implantation conditions that ensure the concentration of the incorporated impurity that exceeds the theoretically possible solubility limit and results in the subsequent high-temperature processing to form an endotaxial dielectric layer at least one monolayer thick, but not residual for ionic synthesis of precipitates within the implantation region; to transfer a layer of semiconductor material, a weakened zone is formed in the donor substrate, which releases a layer of semiconductor material transferred to the substrate; the substrate and the donor semiconductor substrate are spliced and the layer of the semiconductor material is transferred from the donor substrate to the substrate to form a clipped semiconductor surface layer on the substrate; carry out high-temperature processing under conditions that ensure segregation of the impurity implanted in the amorphous insulating layer to its interface with the semiconductor surface layer cut off and endotaxial growth at the specified boundary of the intermediate insulating layer with the formation of implanted impurity compounds.

Silicon wafers are used as the substrate and the donor substrate.

The creation of a weakened zone in the donor substrate, which releases a layer of semiconductor material transferred to the substrate, is carried out by implantation of hydrogen into the donor substrate, while before the implantation of hydrogen, a protective layer of silicon oxide of 50 nm is grown through which the implantation is carried out and which after implantation is removed. Implantation is carried out using hydrogen ion energy of 140 keV and a dose of 2.5 × 10 ¹⁶ cm ^-2 .

When implanting ions of a slightly soluble and easily segregating impurity of reactive gases into an amorphous insulating layer of ions, nitrogen, N ⁺ , is used as an impurity. To implement implantation conditions that ensure the concentration of the introduced impurity that exceeds the theoretically possible solubility limit and leads to the formation of an endotaxial dielectric layer with a thickness of at least one monolayer, but insufficient for ionic synthesis of precipitates within the implantation region, using a dose of 4 × 10 ¹⁵ cm ^-2 and an energy of 40 keV. The impurity is introduced into an amorphous insulating layer — a thermally grown SiO ₂ layer 300 nm thick.

Before connecting the substrate and the donor substrate, respectively, with an amorphous insulating layer and a semiconductor material layer transferred to the substrate, the weakened zone is transferred to the substrate, the surfaces to be joined are subjected to a process that fuses the substrate and the donor substrate, including cleaning and hydrophilization of the surfaces, followed by washing with an ultra-pure deionized jet water, drying and removal of excess physically adsorbed substances from surfaces. After connecting the substrate and the donor substrate with the indicated surfaces, they are simultaneously spliced and layered along the weakened zone of the donor substrate with the transfer of a layer of semiconductor material onto the substrate. Drying and removal of excess physically adsorbed substances from the surfaces is carried out at 200 ° C for 0.1 hour, the subsequent connection of the substrate and the donor substrate, splicing and delamination with transfer is carried out at 350 ° C for 1 hour in a chamber with a vacuum of 10 ³ Pa .

High-temperature treatment under conditions ensuring segregation of the impurity implanted in the amorphous insulating layer to its interface with the cut off surface layer of the semiconductor material and endotaxial growth at the indicated boundary of the intermediate insulating layer with the formation of compounds with an implanted impurity is carried out at 1100 ° C for a duration of 0.5 hours nitrogen atmosphere. In this case, silicon nitride is formed with a thickness of the order of one monolayer.

As a result, a SOI structure is produced that is free of dislocation and mismatch defects, containing successively in the direction of the substrate layers: 0.6 μm Si, 1 monolayer Si ₃ N ₄ , 0.30 μm SiO ₂ on the Si substrate.

Example 8

To fabricate the SOI structure, a sequence of steps is carried out: an amorphous insulating layer is formed on the surface of the substrate, after the formation of ions of a poorly soluble and easily segregating impurity of reactive gases, implantation is carried out under implantation conditions that ensure the concentration of the incorporated impurity that exceeds the theoretically possible solubility limit and results in the subsequent high-temperature processing to form an endotaxial dielectric layer at least one monolayer thick, but not residual for ionic synthesis of precipitates within the implantation region; to transfer a layer of semiconductor material, a weakened zone is formed in the donor substrate, which releases a layer of semiconductor material transferred to the substrate; the substrate and the donor semiconductor substrate are spliced and the layer of the semiconductor material is transferred from the donor substrate to the substrate to form a clipped semiconductor surface layer on the substrate; carry out high-temperature processing under conditions that ensure segregation of the impurity implanted in the amorphous insulating layer to its interface with the semiconductor surface layer cut off and endotaxial growth at the specified boundary of the intermediate insulating layer with the formation of implanted impurity compounds.

Silicon wafers are used as the substrate and the donor substrate.

The creation of a weakened zone in the donor substrate, which releases a layer of semiconductor material transferred to the substrate, is carried out by implantation of hydrogen into the donor substrate, while before the implantation of hydrogen, a protective layer of silicon oxide of 50 nm is grown through which the implantation is carried out and which after implantation is removed. Implantation is carried out using hydrogen ion energy of 140 keV and a dose of 2.5 × 10 ¹⁶ cm ^-2 .

When implanting ions of a slightly soluble and easily segregating impurity of reactive gases into an amorphous insulating layer of ions, nitrogen, N ⁺ , is used as an impurity. To implement implantation conditions that ensure the concentration of the introduced impurity that exceeds the theoretically possible solubility limit and leads to the formation of an endotaxial dielectric layer with a thickness of at least one monolayer, but insufficient for ionic synthesis of precipitates within the implantation region, using a dose of 4 × 10 ¹⁵ cm ^-2 and an energy of 40 keV. The impurity is introduced into an amorphous insulating layer — a thermally grown SiO ₂ layer 300 nm thick.

Before connecting the substrate and the donor substrate, respectively, with an amorphous insulating layer and a semiconductor material layer transferred to the substrate, the weakened zone is transferred to the substrate, the surfaces to be joined are subjected to a process that fuses the substrate and the donor substrate, including cleaning and hydrophilization of the surfaces, followed by washing with an ultrapure deionized water jet, drying and removal of excess physically adsorbed substances from surfaces. After the substrate and the donor substrate are joined by the indicated surfaces, they are simultaneously spliced and layered along the weakened area of the donor substrate with the transfer of a layer of semiconductor material onto the substrate. Drying and removal of excess physically adsorbed substances from surfaces is carried out at 200 ° C for 0.1 hour, subsequent connection of the substrate and the donor substrate, splicing and delamination with transfer is carried out at 450 ° C for 1 hour in a chamber with a vacuum of 10 ¹ Pa .

High-temperature treatment under conditions ensuring segregation of the impurity implanted in the amorphous insulating layer to its interface with the cut off surface layer of the semiconductor material and endotaxial growth at the indicated boundary of the intermediate insulating layer with the formation of compounds with an implanted impurity is carried out at 1150 ° C for a duration of 0.2 hours in an atmosphere of nitrogen. In this case, silicon nitride is formed with a thickness of the order of one monolayer.

As a result, a SOI structure is produced that is free from dislocation and mismatch defects, containing successively in the direction of the substrate layers: 0.6 μm Si, 1 monolayer Si ₃ N ₄ , 0.30 μm SiO ₂ on the Si substrate.

Thus, the positive effect of the proposed method of manufacturing a silicon-on-insulator structure is:

1. Elimination of the need to create a broken layer between the amorphous intermediate insulating layer and the amorphous insulating layer on the substrate and the absence of microvoids and imperfections at the interface between the insulating layers as a result of the formation of an intermediate insulating layer due to implantation of impurity ions into the amorphous medium of the insulating layer and their subsequent segregation to the interface between the single-crystal cut-off surface layer of the semiconductor and the amorphous insulating layer and endotaxial growth by second intermediate insulating layer.

2. Preservation of the atomically smooth interface between the single-crystal cut-off surface layer of the semiconductor and the amorphous insulating layer due to the use of a highly perfect silicon layer transferred from another wafer as an endotaxial seed.

3. A decrease in the density of the built-in charges at the interface between the single-crystal severed surface layer of the semiconductor and the insulating amorphous layer due to the perfection of the interface and the closure of dangling bonds in the process of segregation of nitrogen atoms with subsequent endotaxial growth of the film of silicon nitride or oxynitride as a result of high-temperature effects.

4. Decrease in the rate of charge accumulation in the formed silicon-on-insulator structure during subsequent ionizing effects due to compensation of traps of positive charges generated in the silicon dioxide layer by traps of negative charges generated in silicon nitride.

These advantages are the result of the formation of atomically smooth interfaces between the single-crystal severed surface layer of the semiconductor and the forming intermediate insulating layer, as well as between the insulating layers due to implantation of impurity ions into the amorphous insulating layer with its subsequent segregation and endotaxial growth at the splicing boundary as a result of high-temperature exposure, and not due to the formation of a broken or porous layer, as in the well-known technical solutions.

Claims (7)

1. A method of manufacturing a silicon structure on an insulator, which consists in the following: the insulating layer is formed on the surface of the substrate, the substrate and the donor semiconductor substrate are spliced and a layer of semiconductor material is transferred from the donor substrate to the substrate with the formation of a cut-off surface layer of the semiconductor on a substrate, and the transfer of a layer of semiconductor material is carried out by preliminary, before splicing, the creation of a weakened in the donor substrate zone, emitting a layer of semiconductor material transferred onto a substrate, characterized in that the insulating layer is formed amorphous, after the formation of the amorphous insulating layer, ions of weakly soluble and easily segregating impurities of reactive gases are implanted under the implantation conditions, providing a concentration of embedded impurity exceeding theoretically possible solubility limit and subsequent high-temperature processing leads to the formation of an endotaxial layer of a dielectric of a thickness at least one monolayer, but insufficient for ionic synthesis of precipitates within the implantation region, before the splicing, the substrate and the donor substrate are joined by an amorphous insulating layer and a semiconductor material layer transferred onto the substrate, selected after the transfer, and after the transfer is completed and a cut-off surface layer is formed on the substrate semiconductor conduct high-temperature processing under conditions that ensure segregation of impurities implanted in an amorphous insulating layer to its interface la with a cut off surface layer of the semiconductor and endotaxial growth at the specified boundary of the intermediate insulating layer with the formation of compounds of the implanted impurity. 2. The method according to claim 1, characterized in that silicon wafers are used as the substrate and the donor substrate. 3. The method according to claim 1, characterized in that the creation of a weakened zone in the donor substrate, releasing a layer of semiconductor material transferred to the substrate, is carried out by implantation of hydrogen into the donor substrate, while a protective layer is grown before the implantation of hydrogen on the donor substrate silicon oxide through which implantation is carried out and which is removed after implantation. 4. The method according to claim 1, characterized in that prior to the connection of the substrate and the donor substrate, respectively, with an amorphous insulating layer and a semiconductor material layer transferred to the substrate with a weakened zone, their surfaces to be joined are subjected to a process that fuses the substrate and the donor substrate including cleaning and hydrophilization of surfaces, subsequent washing with a jet of ultrapure deionized water, drying and removal of excess physically adsorbed substances from surfaces, after connecting the substrates and donor substrates with said surfaces, they are simultaneously spliced and delaminated along the weakened zone of the donor substrate with the transfer of a layer of semiconductor material onto the substrate, and drying and removal of excess physically adsorbed substances from the surfaces, connection of the substrate and the donor substrate, and splicing and delamination with transfer are carried out at varying temperature from 80 to 450 ° C, with duration of procedures from 0.1 to 100 hours, in a chamber with a vacuum of 10 ¹ ÷ 10 ³ Pa or in combination with the use of a dry atmosphere. 5. The method according to claim 3, characterized in that the implantation in the substrate of the hydrogen donor is carried out using the energy of hydrogen ions 20 ÷ 200 keV and doses of 2 · 10 ¹⁶ ÷ 1 · 10 ¹⁷ cm ^-2 . 6. The method according to claim 1, characterized in that the implantation in the amorphous insulating layer of ions of poorly soluble and easily segregating impurities of reactive gases under implantation conditions, providing an embedded impurity concentration exceeding the theoretically possible solubility limit and leading to the formation of an endotaxial layer during high-temperature processing dielectric with a thickness of at least one monolayer, but insufficient for ionic synthesis of precipitates within the implantation region, such as the dose of ions 1 · 10 ¹⁵ ÷ 1 · 10 ^{1 6} cm ^-2 and an energy of 20-80 keV, while nitrogen is used as an impurity, and a layer of SiO ₂ is used as an amorphous insulating layer. 7. The method according to claim 1 or 6, characterized in that the high-temperature treatment is carried out under conditions ensuring segregation of the impurity implanted in the amorphous insulating layer to its interface with the sealed surface layer of the semiconductor material and endotaxial growth at the specified boundary of the intermediate insulating layer with the formation of compounds with an implanted impurity, such as a temperature of 1000 ÷ 1200 ° C and a duration of 0.1 ÷ 1 h, and silicon nitride or oxynitride is formed as compounds with an implanted impurity.

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