CN108231950B - Semiconductor homogeneous substrate and preparation method thereof, and preparation method of homogeneous epitaxial layer - Google Patents

Semiconductor homogeneous substrate and preparation method thereof, and preparation method of homogeneous epitaxial layer Download PDF

Info

Publication number
CN108231950B
CN108231950B CN201611199810.XA CN201611199810A CN108231950B CN 108231950 B CN108231950 B CN 108231950B CN 201611199810 A CN201611199810 A CN 201611199810A CN 108231950 B CN108231950 B CN 108231950B
Authority
CN
China
Prior art keywords
periodic structure
substrate
melt
semiconductor
homogeneous
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN201611199810.XA
Other languages
Chinese (zh)
Other versions
CN108231950A (en
Inventor
刘东方
张伟
曾煌
王聪
李纪周
陈小源
鲁林峰
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Shanghai Advanced Research Institute of CAS
Original Assignee
Shanghai Advanced Research Institute of CAS
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Shanghai Advanced Research Institute of CAS filed Critical Shanghai Advanced Research Institute of CAS
Priority to CN201611199810.XA priority Critical patent/CN108231950B/en
Publication of CN108231950A publication Critical patent/CN108231950A/en
Application granted granted Critical
Publication of CN108231950B publication Critical patent/CN108231950B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L31/00—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L31/18—Processes or apparatus specially adapted for the manufacture or treatment of these devices or of parts thereof
    • H01L31/184—Processes or apparatus specially adapted for the manufacture or treatment of these devices or of parts thereof the active layers comprising only AIIIBV compounds, e.g. GaAs, InP
    • H01L31/1856—Processes or apparatus specially adapted for the manufacture or treatment of these devices or of parts thereof the active layers comprising only AIIIBV compounds, e.g. GaAs, InP comprising nitride compounds, e.g. GaN
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/02104—Forming layers
    • H01L21/02365—Forming inorganic semiconducting materials on a substrate
    • H01L21/02367—Substrates
    • H01L21/0237—Materials
    • H01L21/02387—Group 13/15 materials
    • H01L21/02389—Nitrides
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/02104—Forming layers
    • H01L21/02365—Forming inorganic semiconducting materials on a substrate
    • H01L21/02367—Substrates
    • H01L21/02428—Structure
    • H01L21/0243—Surface structure
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/02104—Forming layers
    • H01L21/02365—Forming inorganic semiconducting materials on a substrate
    • H01L21/02436—Intermediate layers between substrates and deposited layers
    • H01L21/02439—Materials
    • H01L21/02488—Insulating materials
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L31/00—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L31/0248—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by their semiconductor bodies
    • H01L31/0256—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by their semiconductor bodies characterised by the material
    • H01L31/0264—Inorganic materials
    • H01L31/0304—Inorganic materials including, apart from doping materials or other impurities, only AIIIBV compounds
    • H01L31/03044—Inorganic materials including, apart from doping materials or other impurities, only AIIIBV compounds comprising a nitride compounds, e.g. GaN
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L31/00—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L31/0248—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by their semiconductor bodies
    • H01L31/0352—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by their semiconductor bodies characterised by their shape or by the shapes, relative sizes or disposition of the semiconductor regions
    • H01L31/035272—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by their semiconductor bodies characterised by their shape or by the shapes, relative sizes or disposition of the semiconductor regions characterised by at least one potential jump barrier or surface barrier
    • H01L31/035281—Shape of the body
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L31/00—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L31/18—Processes or apparatus specially adapted for the manufacture or treatment of these devices or of parts thereof
    • H01L31/1892—Processes or apparatus specially adapted for the manufacture or treatment of these devices or of parts thereof methods involving the use of temporary, removable substrates
    • H01L31/1896—Processes or apparatus specially adapted for the manufacture or treatment of these devices or of parts thereof methods involving the use of temporary, removable substrates for thin-film semiconductors
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
    • Y02P70/50—Manufacturing or production processes characterised by the final manufactured product

Abstract

The invention provides a semiconductor homogeneous substrate, a preparation method thereof and a preparation method of a homogeneous epitaxial layer, wherein the preparation method of the semiconductor homogeneous substrate at least comprises the following steps: providing a mother substrate; forming a periodic structure at least consisting of a plurality of periodic structure units on the surface of the mother substrate; forming an epitaxial barrier layer for realizing selective epitaxial growth on the surfaces of the mother substrate and the periodic structure; and selectively removing the epitaxial barrier layer from the top of each periodic structure unit to form an outward protruding seed crystal correspondingly, thereby forming a seed crystal array formed by at least a plurality of outward protruding seed crystals and finally obtaining the semiconductor homogeneous substrate. The semiconductor homogeneous substrate which can be repeatedly used is utilized to carry out homogeneous epitaxial growth, and a homogeneous epitaxial layer which can be stripped and transferred and has controllable thickness is directly obtained. The technique can avoid the traditional single crystal ingot pulling and slicing processes, thereby realizing the production of homoepitaxial wafers with low cost and high material utilization efficiency.

Description

Semiconductor homogeneous substrate and preparation method thereof, and preparation method of homogeneous epitaxial layer
Technical Field
The invention relates to the technical field of semiconductor material preparation, in particular to a semiconductor homogeneous substrate and a preparation method thereof, and a preparation method of a homogeneous epitaxial layer.
background
Semiconductor technology is a cornerstone of modern high-tech industries, and semiconductor materials have been developed In three stages, including Si and Ge In the first generation, GaAs (including alloys thereof such as In and P) In the second generation, and GaN (including alloys thereof such as In and Al), ZnO, and SiC In the third generation. In current semiconductor technology, single crystal materials are a necessary prerequisite for the realization of high performance semiconductor devices.
Currently, single crystal semiconductor materials are mainly obtained by single crystal ingot wire cutting to obtain wafers (e.g., Si, Ge, GaAs, SiC, etc.), or by epitaxial growth of heterogeneous single crystal substrates to obtain single crystal thin films (e.g., GaN series). However, the conventional wire cutting process causes a lot of material waste, for example, a wafer 170 μm thick is obtained using a 100 μm thick cutting line, which causes more than 50% material loss, and a thin wafer (several micrometers to several tens of micrometers thick enough to realize most of functions of semiconductor devices) cannot be obtained by the conventional wire cutting technique due to a high breakage rate. For GaN, due to its high melting point and high dissociation pressure, bulk single crystal growth is extremely difficult, and commercially, sapphire or SiC substrates are generally adopted for heteroepitaxial growth of single crystal films, but the lattice mismatch between sapphire and GaN is 13.9%, and the thermal mismatch is 30%, and this high thermal mismatch and lattice mismatch can generate high dislocation density in the epitaxial films, which affects the crystal quality; on the other hand, although SiC has little lattice mismatch and thermal mismatch with GaN, SiC has poor wettability with GaN, a buffer layer needs to be added, the buffer layer generally has higher dislocation density, and the epitaxial GaN thin film also has higher dislocation density.
In terms of device design, the low thermal and electrical conductivity of sapphire and the strong absorption of light by the silicon carbide substrate also greatly hinder the development of high-power LEDs. In addition, for the GaAs-based III-V group multi-junction solar cell, junction units with different band gap widths are generally grown by continuous epitaxial growth by taking a Ge or GaAs single crystal wafer as a substrate, and in order to obtain high crystal quality, lattice matching between materials of adjacent junction layers must be ensured; in order to obtain the best photovoltaic conversion efficiency, the junction layers are required to be matched with each other in a band gap mode, that is, the distribution of the band gap is matched with the solar spectrum, so that the photoelectric conversion can be realized to the maximum extent, but usually, the lattice matching and the band gap matching cannot be realized at the same time, a lattice graded layer needs to be inserted between different junction materials to eliminate lattice mismatch, and an epitaxial barrier layer needs to be added to prevent components between different junction layers from diffusing, so that the manufacturing process of the III-V group multi-junction solar cell is extremely complex, tedious, time-consuming and expensive.
In short, the current semiconductor technology has several difficulties: the wafer cutting technology has a great deal of material waste; the GaN-based semiconductor lacks a homogeneous substrate, and a large amount of space for improving the quality of a film and the performance of a device exists; the GaAs-based epitaxial laminated device is designed by lattice matching and band gap matching, so that the process cost is high; the thickness of the wafer can be selected with small freedom, which is not beneficial to the development of light and flexible devices and the reasonable design of relevant aspects such as electric conduction, heat conduction and optics.
Therefore, it is an urgent need to solve the above-mentioned semiconductor technology problem to prepare a transferable and thickness-controllable single crystal wafer or film.
disclosure of Invention
In view of the above-mentioned drawbacks of the prior art, an object of the present invention is to provide a semiconductor homogeneous substrate, a method for manufacturing the same, and a method for manufacturing a homogeneous epitaxial layer, which are used to solve the problem of a lot of material waste in the wafer dicing technology in the prior art; the GaN-based semiconductor lacks a homogeneous substrate, and a large amount of space for improving the quality of a film and the performance of a device exists; the GaAs-based epitaxial laminated device is designed by lattice matching and band gap matching, so that the process cost is high; the degree of freedom in selecting the thickness of the wafer is small, which is not beneficial to the development of light and flexible devices and the problems of reasonable design in the aspects of relevant electric conduction, heat conduction, optics and the like.
In order to achieve the above and other related objects, the present invention provides a method for manufacturing a semiconductor homogeneous substrate, wherein the method for manufacturing the semiconductor homogeneous substrate at least comprises the following steps:
Providing a mother substrate;
Forming a periodic structure at least consisting of a plurality of periodic structure units on the surface of the mother substrate;
forming an epitaxial barrier layer for realizing selective epitaxial growth on the surfaces of the mother substrate and the periodic structure;
And correspondingly forming an outward protruding seed crystal at the top of each periodic structure unit, thereby forming a seed crystal array at least consisting of a plurality of outward protruding seed crystals and finally obtaining the semiconductor homogeneous substrate.
preferably, a periodic structure at least composed of a plurality of periodic structure units is formed on the surface of the mother substrate, and the specific method is as follows:
Forming a mask layer with a preset periodic structure pattern on the surface of the mother substrate;
Forming a periodic structure on the mother substrate based on the pattern of the mask layer, wherein the periodic structure at least comprises a plurality of periodic structure units which are arranged in an array and have the same shape;
And removing the mask layer.
Preferably, an outwardly protruding seed crystal is correspondingly formed at the top of each periodic structure unit, so as to form a seed crystal array at least composed of a plurality of outwardly protruding seed crystals, and the specific method is as follows:
filling a melt on the epitaxial barrier layer and among the periodic structure units of the periodic structure, and solidifying;
Removing the melt solidified substance and the corresponding epitaxial barrier layer on the top of each periodic structure unit of the periodic structure to expose the top of each periodic structure unit of the periodic structure;
And removing the residual melt solidified substances to enable the exposed top of each periodic structure unit to be used as an outward protruding seed crystal, and simultaneously enabling the part of each periodic structure unit, which is covered by the epitaxial barrier layer, to be used as a supporting part of the outward protruding seed crystal, so that a seed crystal array at least consisting of a plurality of outward protruding seed crystals is formed, and finally the semiconductor homogeneous substrate is obtained.
Preferably, a melt is filled on the epitaxial barrier layer and between each periodic structure unit of the periodic structure, and is solidified, and the specific method is as follows:
immersing the substrate structure with the epitaxial barrier layer formed in a melt, taking out the substrate structure and placing the substrate structure in an inclined mode, keeping the ambient temperature higher than the melting point of the melt substance, enabling gaps on the epitaxial barrier layer and among all periodic structure units of the periodic structure to be filled with the melt, and enabling redundant melt to automatically flow away from the surface of the substrate structure;
horizontally placing the substrate structure filled with the melt, keeping the ambient temperature higher than the melting point of the melt substance, and standing to ensure that the melt is uniformly filled among the periodic structure units of the periodic structure;
The substrate structure after standing was cooled to room temperature to solidify the melt.
Preferably, the melt solidified substance and the corresponding epitaxial barrier layer on the top of each periodic structure unit of the periodic structure are removed to expose the top of each periodic structure unit of the periodic structure, and the specific method is as follows:
Placing the substrate structure after solidifying the melt in a low-solubility solvent to enable the melt solidified substance to be slightly soluble, and removing the melt solidified substance on the top of each periodic structure unit of the periodic structure to expose the epitaxial barrier layer on the top of each periodic structure unit of the periodic structure;
And removing the epitaxial barrier layer on the top of each periodic structure unit of the periodic structure to expose the top of each periodic structure unit of the periodic structure.
preferably, the low-solubility solvent is an organic solvent that is controllable to slowly dissolve away melt solidified material atop individual periodic structure units of the periodic structure.
Preferably, in removing the remaining melt-solidified substance, the remaining melt-solidified substance is completely dissolved and removed using a high-solubility solvent, which is an organic solvent that can rapidly dissolve and completely remove the remaining melt-solidified substance.
Preferably, the melt is a liquid obtained by melting a hydrophobic organic solid substance which has a melting temperature of 300 ℃ or lower and is soluble in an organic solvent.
preferably, the low-solubility solvent is an organic solvent that controllably removes melt solidified material on top of each periodic structure unit of the periodic structure in a slow dissolution.
Preferably, a diffusion stopping layer for stopping oxygen from diffusing into the semiconductor is further formed between the surfaces of the mother substrate and the periodic structure and the epitaxial barrier layer; and when the melt solidified substance and the epitaxial barrier layer on the top of each periodic structure unit of the periodic structure are removed, removing the diffusion barrier layer at the corresponding position to expose the top of each periodic structure unit of the periodic structure.
Preferably, the periodic structure unit is in a column shape, a strip shape, a belt shape, a wave shape, a cone shape or an irregular shape.
Preferably, the mother substrate is a single crystal wafer or a target semiconductor epitaxial single crystal thin film grown on a hetero single crystal wafer.
To achieve the above and other related objects, the present invention also provides a semiconductor homogeneous substrate, wherein the semiconductor homogeneous substrate at least comprises:
a mother substrate;
the periodic structure at least consists of a plurality of periodic structure units and is formed on the surface of the mother substrate;
The epitaxial barrier layer is formed on the surface of the mother substrate and the surface of the periodic structure and used for realizing selective epitaxial growth;
Corresponding to the outward protruding seed crystal formed on the top of each periodic structure unit, thereby forming a seed crystal array at least consisting of a plurality of outward protruding seed crystals.
Preferably, the periodic structure unit is in a column shape, a strip shape, a belt shape, a wave shape, a cone shape or an irregular shape.
preferably, the mother substrate is a single crystal wafer or a target semiconductor epitaxial single crystal thin film grown on a hetero single crystal wafer.
In order to achieve the above and other related objects, the present invention further provides a method for preparing a homogeneous epitaxial layer, wherein the method for preparing a homogeneous epitaxial layer at least comprises the following steps:
Preparing the semiconductor homogeneous substrate by adopting the preparation method of the semiconductor homogeneous substrate;
Forming a homogeneous epitaxial layer on the semiconductor homogeneous substrate, wherein the homogeneous epitaxial layer is an epitaxial single crystal wafer or a film;
Peeling and transferring the homogeneous epitaxial layer from the semiconductor homogeneous substrate;
and the semiconductor homogeneous substrate after the homogeneous epitaxial layer is stripped and transferred is suitable for being repeatedly used in the step of forming the homogeneous epitaxial layer.
Preferably, a homogeneous epitaxial layer is formed on the semiconductor homogeneous substrate, and the specific method is as follows:
Selectively performing homoepitaxial growth on the semiconductor homoepitaxial substrate to grow and combine discrete protruded seed crystals in the seed crystal array to form a nonporous continuous epitaxial single crystal wafer or film, thereby obtaining a homoepitaxial layer with the same chemical composition as the protruded seed crystals; and the homogeneous epitaxial layer is connected with the mother substrate through the part of each periodic structure unit of the periodic structure, which is coated by the epitaxial barrier layer.
Preferably, after the semiconductor homogeneous substrate is repeatedly used for a plurality of times, before the homogeneous epitaxial layer is peeled off from the semiconductor homogeneous substrate and transferred, the epitaxial barrier layer coated outside each periodic structure unit in the semiconductor homogeneous substrate is thickened, so that the reusability of the semiconductor homogeneous substrate is recovered.
as described above, the semiconductor homogeneous substrate technology method of the present invention has the following beneficial effects:
the semiconductor homogeneous substrate can utilize gas-phase reactants to directly epitaxially grow a single crystal wafer or a film, the thickness is simply controlled by the growth time, the material loss caused by the traditional wafer cutting process is avoided, and the material resources are fully utilized; furthermore, rapid and simple mechanical or chemical etching, peeling and transfer of the grown wafer or film can be performed. In addition, the periodic structure units which are uniformly distributed can provide stable mechanical support for the thin wafer or the thin film which is grown in a subsequent gas phase, and the thin wafer or the thin film can be conveniently processed on the basis of the mother substrate without cracking. In addition, the wafer cleaning agent can be subjected to a traditional wafer cleaning process, is not easy to damage and can be recycled.
The preparation method of the semiconductor homogeneous substrate can conveniently utilize the thin wafer or the thin film to realize the processing of flexible and light devices, and further save material resources; moreover, the problems of lattice mismatch and thermal mismatch caused by lack of a single crystal in the GaN-based semiconductor technology are solved fundamentally, a high-crystal-quality GaN wafer or film is obtained, and the design of the device in the aspects of electricity, optics and the like can be more reasonable; in addition, GaAs-based single-junction flexible thin cells with different band gap widths can be conveniently realized, further, mechanical stacking can be carried out to form a multi-junction solar cell, the complex process generated by the traditional epitaxial stacking is avoided, the multi-junction solar cell can be formed by the GaAs-based single-junction flexible thin cells and Ge, Si and GaN series flexible thin cells, more band gap layout freedom is provided for the design of the multi-junction solar cell, the photovoltaic conversion efficiency is improved, and the cost of the multi-junction solar cell is reduced.
According to the preparation method of the homogeneous epitaxial layer, on the basis of the preparation method of the semiconductor homogeneous substrate, the single crystal wafer or the film is directly epitaxially grown, the thickness is simply controlled by the growth time, the material loss caused by the traditional wafer cutting process is avoided, and the material resource is fully utilized; furthermore, the wafer or the film can be directly peeled and transferred by quick and simple mechanical or chemical etching. In addition, the semiconductor substrate can be reused, and material resources are saved. In addition, the obtained thin wafer or thin film provides stable mechanical support by the periodic structure units with uniform distribution, and the thin wafer or thin film is convenient to carry out various device processing depending on the mother substrate without cracking.
Drawings
Fig. 1 is a schematic flow chart showing a method for manufacturing a semiconductor homogeneous substrate according to a first embodiment of the present invention.
Fig. 2 to 15 are schematic views showing a method for manufacturing a semiconductor native substrate according to a first embodiment of the present invention.
Fig. 15 is a schematic view of a semiconductor homogeneous substrate according to a second embodiment of the present invention.
Fig. 16 is a flow chart showing a method for preparing a homoepitaxial layer according to a third embodiment of the present invention.
Fig. 17 to 19 are schematic views showing a method for preparing a homoepitaxial layer according to a third embodiment of the present invention.
Description of the element reference numerals
101 mother substrate
102 mask layer
103 periodic structure unit
104 epitaxial barrier layer
105 melt/melt material/melt solidified material
106 outward protruding type seed crystal
107 epitaxial growth layer
S1-S7
Detailed Description
The embodiments of the present invention are described below with reference to specific embodiments, and other advantages and effects of the present invention will be easily understood by those skilled in the art from the disclosure of the present specification. The invention is capable of other and different embodiments and of being practiced or of being carried out in various ways, and its several details are capable of modification in various respects, all without departing from the spirit and scope of the present invention.
Referring to fig. 1 to 18, a first embodiment of the present invention relates to a method for manufacturing a semiconductor homogeneous substrate. It should be noted that the drawings provided in the present embodiment are only for illustrating the basic idea of the present invention, and the components related to the present invention are only shown in the drawings rather than drawn according to the number, shape and size of the components in actual implementation, and the form, quantity and proportion of each component in actual implementation may be changed freely, and the layout of the components may be more complicated.
As shown in fig. 1, the method for manufacturing a semiconductor homogeneous substrate according to this embodiment at least includes the following steps:
In step S1, a mother substrate 101 is provided, as shown in fig. 2.
In step S1, the mother substrate 101 is a single crystal wafer or a target semiconductor epitaxial single crystal thin film grown on a hetero single crystal wafer. The mother substrate 101 in this embodiment has a certain versatility, and can be made of most semiconductor materials, such as Si, Ge, GaAs-based, GaN-based, and the like, without crystal orientation limitation, and is suitable for a single crystal wafer or a semiconductor epitaxial single crystal thin film having an arbitrary crystal orientation.
step S2 is to form a periodic structure composed of at least several periodic structure units 103 on the surface of the mother substrate 101, as shown in fig. 3 to 6.
In step S2, the specific method is:
In step S21, a mask layer 102 having a predetermined periodic structure pattern is formed on the surface of the mother substrate 101, as shown in fig. 3 and 4. Fig. 3 is a top view of fig. 4, and since the mask layer 102 is used for manufacturing a periodic structure in a subsequent process, a periodic structure pattern needs to be formed in the mask layer 102 first; in this embodiment, a conventional uv exposure lithography process is used to form a periodic structure pattern preset in the mask layer 102 according to an actually required periodic structure pattern. Of course, in other embodiments, other processes may be used to form the pattern in the mask layer 102.
Step S22, forming a periodic structure on the mother substrate 101 based on the pattern of the mask layer 102, wherein the periodic structure at least includes a plurality of periodic structure units 103 with the same shape arranged in an array, as shown in fig. 5. In the embodiment, since the mask layer 102 includes the preset periodic structure pattern, the pattern in the mask layer 102 is transferred to the mother substrate 101 by using the dry etching method using the inductively coupled plasma, so that the periodic structure pattern identical to the preset periodic structure pattern is formed on the mother substrate 101. Of course, in other embodiments, other processes may be used to form the periodic structure pattern on the mother substrate 101.
In step S23, the mask layer 102 is removed, as shown in fig. 6. In this embodiment, the mask layer 102 is removed by dissolving with acetone. Of course, in other embodiments, other organic solvents may be used to dissolve and remove the mask layer 102.
In addition, the periodic structure unit 103 is in the shape of a column, a stripe, a band, a wave, a cone, or other regular and irregular shapes. In the present embodiment, the periodic structure unit 103 is a columnar shape as an example.
In step S3, an epitaxial barrier layer 104 for selective epitaxial growth is formed on the surface of the mother substrate 101 and the periodic structure, as shown in fig. 7.
as an example, the epitaxial barrier layer is a SiO 2 layer.
as an example, a SiO 2 layer is formed by a Plasma-enhanced atomic layer deposition (PE-ALD) method, a SiO 2 layer with a uniform thickness is formed on the surface of the mother substrate 101 and the surface of each periodic structure unit 103 of the periodic structure (including the upper surface and the sidewall surface) by utilizing atomic-level uniformity of ALD growth, and the mother substrate 101 is prevented from being damaged by an oxidizing atmosphere in a high-temperature environment by utilizing the low-temperature growth characteristics (less than 300 ℃) of PE-ALD.
step S4, forming an outwardly protruding seed crystal on the top of each periodic structure unit, so as to form a seed crystal array composed of at least several outwardly protruding seed crystals, and finally obtaining a semiconductor homogeneous substrate, as shown in fig. 8 to 15.
In step S4, the specific method is:
Step S41 is to fill the melt 105 on the epitaxial barrier layer 104 and between the periodic structure units 103 of the periodic structure, and solidify the melt, as shown in fig. 8 to 12. Wherein, at least comprises the following steps:
Step S411, immersing the substrate structure with the epitaxial barrier layer 104 formed thereon in a melt 105, taking out and placing the substrate structure obliquely, and maintaining the ambient temperature higher than the melting point of the melt 105, so that the gaps on the epitaxial barrier layer 104 and between the periodic structure units 103 of the periodic structure are filled with the melt 105, and the excess melt 105 automatically flows away from the surface of the substrate structure, as shown in fig. 8 to 10. Specifically, the substrate structure after the epitaxial barrier layer 104 is formed is immersed in a melt 105, wherein the melt 105 is a liquid obtained by melting a hydrophobic organic solid substance having a melting temperature of 300 ℃ or less and capable of being dissolved in an organic solvent, such as: paraffin, hot melt adhesive and the like, wherein the melt 105 is the molten liquid of the substances; the substrate structure is then removed and tilted, and a tilt frame may be used, and the removed substrate structure is placed on the tilt frame and the ambient temperature is maintained above the melting point of the melt 105, such that the voids between the periodic structure elements 103 are filled with the melt 105 and excess melt 105 automatically drains away from the surface of the substrate structure. In addition, the angle at which the substrate structure is tilted after being removed from the melt 105 can be adjusted by adjusting the angle of the tilt support, thereby controlling the rate at which excess melt 105 automatically flows off the surface of the substrate structure.
it should be explained that, under the environment of temperature higher than melting point of the melt substance 105, the substrate structure with periodic structure is immersed in the melt 105, the melt 105 can spontaneously remove air to fill the gap between the periodic structure units 103, the filling is implemented without substrate size limitation, only the area of the melt 105 is required to be larger than that of the mother substrate 101, and the method is suitable for the mother substrate 101 with any size; meanwhile, in a temperature environment higher than the melting point of the melt substance 105, the melt 105 has sufficient fluidity, when the substrate structure is placed obliquely (when the periodic structure units 103 are in a strip or belt shape, the substrate structure is inclined in a direction perpendicular to the strip and belt directions), the melt 105 higher than the tops of the periodic structure units 103 will automatically flow off the surface of the substrate structure, and the melt 105 between the periodic structure units 103 is retained due to the blocking effect of the periodic structure and the viscosity of the melt substance 105.
Step S412, the substrate structure filled with the melt 105 is horizontally placed, and still the ambient temperature is maintained higher than the melting point of the melt substance, and is left to stand so that the melt 105 is uniformly filled between the respective periodic structure units 103 of the periodic structure, as shown in fig. 11. Specifically, the substrate structure filled with the melt 105 is removed from the inclined support, placed in a horizontal position under the same environment, and left for a period of time, thereby ensuring that the melt 105 can be uniformly filled between the individual periodic structure units 103 of the periodic structure.
In step S413, the substrate structure after standing is cooled to room temperature to solidify the melt 105, as shown in fig. 12.
As an example, paraffin wax is used as the melt substance 105, the melting point of which is about 57 ℃, and the heating thermostat system is turned on to keep the ambient temperature at 60 ℃.
As an example, the substrate structure after formation of the epitaxial barrier layer 104 was immersed in the melt 105 for a period of 10 min.
As an example, the substrate structure taken out of the melt 105 was placed tilted at an angle of 60 ° for 60 min.
as an example, the substrate structure filled with the melt 105 is horizontally placed and left standing at an ambient temperature of 60 ℃ for 60min, so that the paraffin melt 105 is uniformly filled in the gaps between the periodic structure units 103.
As an example, the heating constant temperature system is turned off, the substrate structure after standing for 60min is naturally cooled to room temperature, the paraffin melt 105 is cooled and solidified and undergoes a certain amount of volume shrinkage, and the top end part of the periodic structure unit 105 is in a convex state, as shown in fig. 12.
It should be noted that due to the fluidity of melt 105, the filling of melt 105 is self-leveling, without limitation to the size of the substrate, and is suitable for use with mother substrates of various sizes, such as all 4 inch, 6 inch, and 8 inch standard wafer areas of the conventional electronics industry.
in addition, for the selection of the melt 105, the selected melt 105 is required to be wetted with the epitaxial barrier layer 104, the volume shrinkage of the melt 105 after solidification is relatively small, and the melt solidified substance has relatively good toughness or is relatively soft, so that the melt solidified substance 105 is not cracked or separated from the epitaxial barrier layer 104 due to the volume change generated by the physical phase change from a liquid state to a solid state, and therefore, the melt solidified substance 105 is ensured to be tightly bonded with the epitaxial barrier layer 104, and a sufficient wet etching resistance protection effect can be provided for the epitaxial barrier layer 104 covered by the melt solidified substance 105.
in addition, the filling thickness of the melt 105 is determined by the inclination angle of the substrate structure, the ambient temperature and the inclined placement time. Generally speaking, the smaller the viscosity of the melt 105, the larger the angle of inclination of the substrate structure, the higher the ambient temperature, and the longer the time of inclined placement, the smaller the filling thickness of the melt 105; and vice versa. Moreover, the melt substance 105 at all positions in the substrate structure is in a liquid state and has fluidity under the environment with the temperature higher than the melting point; there is a slight difference in the thickness of the melt 105 filled between the periodic structure units 103 in the flow direction of the melt 105, and at an ambient temperature higher than the melting point temperature of the melt, the substrate structure is left standing for an appropriate time to eliminate this difference in thickness due to the self-leveling, i.e., self-uniformity, of the melt 105. Taking paraffin wax molten liquid as an example, the melting point is 57 ℃, the placing environment temperature is 60 ℃, the substrate structure is immersed in the paraffin wax melt for 10min, so that gaps among the periodic structure units 103 can be fully filled, and then the substrate structure is obliquely placed at an angle of 60 degrees for 60min, so that redundant paraffin wax liquid on the surface of the substrate can be fully removed in a flowing manner; and finally, horizontally standing the substrate structure at the ambient temperature of 60 ℃ for 60min to enable the melt 105 to be self-leveled, and eliminating the slight difference of the thickness of the melt 105 filled among the periodic structure units 103.
in addition, the cooling solidification of the melt 105 keeps the filling uniformity of the liquid melt substance, and meanwhile, as the phase of the melt substance changes from liquid to solid, the melt substance shrinks slightly in volume, so that the top end parts of the periodic structure units 103 are in a convex state after the melt 105 is solidified, and the subsequent removal of the melt solidified substance 105 at the top ends of the periodic structure units 103 is facilitated.
Step S42, removing the melt solidified substance and the corresponding epitaxial barrier layer on top of each periodic structure unit of the periodic structure to expose the top of each periodic structure unit of the periodic structure, as shown in fig. 13 and 14. Wherein, at least comprises the following steps:
Step S421, the substrate structure after solidifying the melt 105 is placed in a low-solubility solvent, so that the melt solidified substance 105 is slightly soluble, and the melt solidified substance on the top of each periodic structure unit 103 of the periodic structure is removed to expose the epitaxial barrier layer on the top of each periodic structure unit 103 of the periodic structure, as shown in fig. 13. Among these, the low-solubility solvent is an organic solvent that can control the dissolution rate of the melt solidified substance 105 to slowly dissolve the melt solidified substance on the top of each periodic structure unit 103 of the periodic structure, such as: acetone which is slightly soluble in paraffin.
It is worth mentioning that due to the viscosity of the melt 105, in addition to filling the melt 105 between each periodic structure unit 103, a thin film of the melt may remain on top of each periodic structure unit 103 to a certain thickness. Using a low-solubility solvent for the sparingly soluble melt substance allows a relatively precise control of the amount of melt substance removed by controlling the dissolution time or the amount of solvent, so that only the melt substance 105 on top of the periodic structure elements 103 is removed, leaving the epitaxial barrier layer 104 on top of the periodic structure elements exposed, while the other parts of the epitaxial barrier layer 104 remain coated with the melt substance 105.
as an example, using acetone to slightly dissolve paraffin, the thin layer of paraffin on top of each periodic structure unit 103 was dissolved away, leaving only the SiO 2 layer on top of the periodic structure unit 103 exposed, and the other SiO 2 layer still coated with paraffin.
Step S422 is to remove the epitaxial barrier layer 104 on top of each periodic structure unit 103 of the periodic structure to expose the top of each periodic structure unit 103 of the periodic structure, as shown in fig. 14.
in this embodiment, the epitaxial barrier layer 104 on the top of the periodic structure unit 103 is selectively removed by wet etching, so that only the target semiconductor material on the top of the periodic structure unit 103 is exposed. It should be noted that the etching solution used for etching the epitaxial barrier layer 104 does not chemically react with the melt substance 105, nor makes the melt substance 105 undergo a swelling physical change, so that the melt solidified substance 105 can provide sufficient anti-etching protection for the epitaxial barrier layer 104 covered by the melt solidified substance, etching removal of the epitaxial barrier layer 104 only occurs at the top of the periodic structure unit 103, and the etching depth of the epitaxial barrier layer 104 along the axial direction of the periodic structure unit 103 is controlled by the etching time. Of course, in other embodiments, other processes may be used to remove the epitaxial barrier layer 104 on the top of the periodic structure unit 103.
As an example, a BOE etching solution (HF: NH4F ═ 1:6) is used to selectively etch and remove the SiO 2 layer on the top of the periodic structure unit 103, and the etching time is 3 min.
in addition, in other embodiments, for step S3, a diffusion preventing layer for preventing oxygen from diffusing into the semiconductor can be formed between the surface of the mother substrate 101 and the periodic structure and the epitaxial barrier layer 104, for step S42, when the melt solidified material 105 on the top of each periodic structure unit 103 of the periodic structure and the corresponding epitaxial barrier layer 104 are removed, the diffusion preventing layer at the corresponding position is also removed to expose the top of each periodic structure unit of the periodic structure, for example, the diffusion preventing layer is SiN x, and the plasma enhanced atomic layer deposition method is also used to form on the surface of the mother substrate 101 and the periodic structure.
Step S43, removing the remaining melt-solidified substance 105, so that the exposed top of each periodic structure unit 103 serves as an outwardly projecting seed crystal 106, and the portion of each periodic structure unit 103 covered by the epitaxial barrier layer 104 serves as a support for the outwardly projecting seed crystal 106, thereby forming a seed crystal array composed of at least several outwardly projecting seed crystals 106, as shown in fig. 15. When removing the residual melt solidified substances, dissolving and removing the residual melt solidified substances by using a high-solubility solvent; the high-solubility solvent is an organic solvent that can rapidly dissolve and completely remove the remaining melt-solidified substance 105, such as: the paraffin wax is tetrahydrofuran, toluene, or the like, which does not chemically react with the epitaxial barrier layer 104 nor with the target semiconductor material, and is used only for removing the melt solidified substance 105 in the gap between the periodic structure units 103, thereby realizing the fabrication of the predetermined outwardly protruding seed crystal array.
As an example, tetrahydrofuran is used to dissolve and remove paraffin between the respective periodic structure units 103.
Through the steps S1 to S4, the fabrication of the semiconductor homogeneous substrate is finally and completely achieved.
It should be noted that, because the inductively coupled plasma dry etching technique has been widely applied to the etching processing of semiconductor materials such as Si, Ge, GaAs-based, GaN-based, etc., and SiO 2 is an epitaxial barrier layer material commonly used for these semiconductor crystals to realize selective epitaxial growth, and meanwhile, the ALD method for growing SiO 2 or SiN x is also commonly used for the similar semiconductor materials, the method for preparing the semiconductor homogeneous substrate of the present embodiment has a certain universality, and is applicable to all three generations of semiconductor materials (Si, Ge, GaAs-based, GaN-based).
in addition, by controlling the size of the periodic structure unit 103 in the semiconductor homogeneous substrate, the height of the periodic structure unit 103 is equal to or smaller than the minimum dimension of the end face thereof, so that the periodic structure has sufficient mechanical strength, and the obtained semiconductor homogeneous substrate can be subjected to a conventional wafer cleaning process and is not easily damaged.
in addition, due to the self-flatness of the melt 105 filling and the limitation of substrate-free size, and the highly controllable removal of the melt solidified substance 105 thin film on the top of the periodic structure unit 103 through the slightly soluble solvent, the technical scheme is easy to realize the current semiconductor homogeneous substrate manufacturing (no matter 4 inch wafer, 6 inch wafer or 8 inch wafer) of the standard wafer area in the electronic industry, and the process is simple, stable, reliable, highly controllable and good in repeatability, is suitable for large-scale manufacturing, and is very suitable for industrial scale application.
the steps of the above methods are divided for clarity, and the implementation may be combined into one step or split some steps, and the steps are divided into multiple steps, so long as the steps contain the same logical relationship, which is within the protection scope of the present patent; it is within the scope of the patent to add insignificant modifications to the algorithms or processes or to introduce insignificant design changes to the core design without changing the algorithms or processes.
referring to fig. 15, a second embodiment of the present invention relates to a semiconductor homogeneous substrate, which at least includes:
A mother substrate 101;
A periodic structure formed on the surface of the mother substrate 101 and at least composed of a plurality of periodic structure units 103;
an epitaxial barrier layer 104 formed on the surface of the mother substrate 101 and the periodic structure for realizing selective epitaxial growth;
Corresponding to the projecting seed crystal 106 formed on the top of each periodic structure unit 103, thereby forming a seed crystal array composed of at least several projecting seed crystals 106.
As shown in fig. 15, the protrusion-type seed crystal 106, the periodic structure unit 103, and the mother substrate 101 are an integral structure. The exposed top of each periodic structure unit 103 is an overhang seed 106, and the upper surface and the sidewall surface of the overhang seed 106 are not covered by the selective epitaxial growth mask layer 104.
in addition, the periodic structure unit 103 is in the shape of a column, a stripe, a band, a wave, a cone, or other regular and irregular shapes. The mother substrate 101 is a single crystal wafer or a target semiconductor epitaxial single crystal thin film grown on a hetero single crystal wafer.
the semiconductor homogeneous substrate of this embodiment can be directly subjected to selective homogeneous vapor phase epitaxial growth thereon. When vapor phase epitaxial growth is performed thereon, crystal epitaxial growth occurs only on the top of the periodic structure unit 103, i.e., the extrinsic seed 106, due to the blocking effect of the epitaxial barrier layer 104. Since all the exogenous seed crystals 106 are derived from the same mother substrate 101 single wafer or heteroepitaxial single crystal film and have the same crystal orientation, as the growth of each exogenous seed crystal 106 grows, all the exogenous seed crystals 106 grow and merge into a single crystal film epitaxial layer 107, and the single crystal wafer or the single crystal film epitaxial layer 107 with a predetermined thickness can be obtained through the control of the growth time.
The semiconductor homogeneous substrate of the embodiment can be repeatedly utilized, almost all three generations of semiconductor materials (including Si, Ge, GaAs base, GaN base and the like) can directly obtain a single crystal wafer or a transferable single crystal film with controllable thickness from a gas phase reactant through homoepitaxial growth, so that the development of the traditional wafer technology to the thin wafer technology with low cost and high raw material utilization efficiency is promoted, and the GaN single crystal wafer technology is realized; further promoting the development of flexible, light, efficient and low-cost monocrystalline silicon solar cell technology, promoting the development of GaN high-performance LED technology based on homogeneous substrates, and promoting the development of mechanical laminated multi-junction solar cell technology containing Si, Ge, GaAs and GaN bases.
It is understood that the semiconductor homogeneous substrate of the present embodiment is obtained by the method for producing a semiconductor homogeneous substrate of the first embodiment of the present invention. The related technical details mentioned in the first embodiment are still valid in this embodiment, and are not described herein again in order to reduce repetition. Accordingly, the related-art details mentioned in the present embodiment can also be applied to the first embodiment.
referring to fig. 16 to 19, a third embodiment of the present invention relates to a method for preparing a homoepitaxial layer. Since this embodiment needs to be implemented on the basis of steps S1 to S4 in the first embodiment of the present invention, the details of the related art mentioned in the first embodiment are still valid in this embodiment, and are not described here again in order to reduce the redundancy.
as shown in fig. 16, the method for preparing a homo-epitaxial layer according to this embodiment at least includes the following steps:
By the steps S1 to S4 of the first embodiment of the present invention, a semiconductor homogeneous substrate is prepared.
In step S5, a homoepitaxial layer 107 is formed on the semiconductor homosubstrate, as shown in fig. 16 to 18, wherein the homoepitaxial layer 107 is an epitaxial single crystal wafer or a thin film.
In step S5, the specific method is: selective homoepitaxial growth is performed on a semiconductor native substrate to grow each discrete overhanging seed 106 in the seed array and form a nonporous continuous epitaxial single crystal wafer or film, as shown in fig. 17, resulting in a native epitaxial layer 107 of the same chemical composition as the overhanging seed 106, as shown in fig. 18. The homoepitaxial layer 107 and the mother substrate 101 are connected by the portion of each periodic structure unit 103 of the periodic structure, which is covered with the epitaxial barrier layer 104.
When selective homoepitaxial growth is performed on a semiconductor homosubstrate, it is necessary to selectively grow the homoepitaxial layer 107 on each of the epitaxial seeds 106 by appropriately adjusting the epitaxial growth method and conditions.
As an example, GaAs is epitaxially grown using MOCVD metal organic chemical vapor deposition method using raw materials of trimethylgallium TMGa and arsine AH 3.
As an example, Ge is epitaxially grown using the raw material GeH 4 using a low pressure chemical vapor deposition method.
As an example, MOCVD metal organic chemical vapor deposition is employed to epitaxially grow GaN using the raw materials trimethylgallium TMGa and ammonia NH 3.
As an example, Si is epitaxially grown using an atmospheric pressure chemical vapor deposition method with SiHCl 3 gas as a source.
In addition, it is worth mentioning that as the growth proceeds, the individual discrete outcropping type seed crystals 106 gradually grow up and then gradually merge together to form an epitaxial single crystal wafer or film, and an epitaxial single crystal wafer or film of a predetermined thickness is obtained by controlling the growth time, that is, a semiconductor epitaxial single crystal wafer or film homoepitaxial layer 107 having the same chemical composition as the outcropping type seed crystals 106 is obtained. When selective vapor phase epitaxy is performed, the tops of the periodic structure units 103 are merged due to the lateral growth of the protruding seed crystals 106, so that the gaps between the periodic structure units 103 are reserved, and thus, the epitaxial single crystal wafer or film obtained by performing homoepitaxial growth is connected with the mother substrate 101 only through the periodic structure units 103, and the gaps are formed at other places, so that a uniform and ordered hollow structure is formed, and the hollow structure can be used as a gas channel or a chemical solution channel for some subsequent processing processes, so that chemical etching (wet etching or reactive ion dry etching) can be performed on the lower surface of the homoepitaxial layer 107 before the homoepitaxial layer 107 is transferred, and peeling transfer or other surface processing (such as surface texturing, PE-ALD coating and the like) can be realized. Because the size of each periodic structure unit 103 is uniform, the spatial distribution on the mother substrate 101 is also uniform, so that a relatively stable mechanical support can be provided for the homogeneous epitaxial layer 107, the homogeneous epitaxial layer 107 is convenient to process various devices depending on the mother substrate 101, and the fragmentation is not easy to occur, thereby greatly improving the yield of the flexible device manufacture.
furthermore, by controlling the size and spatial distribution of the periodic structure units 103 and controlling the ratio of the end faces of the periodic structure to the surface area of the mother substrate 101, the ratio is made as small as possible, so that the contact between the homogeneous epitaxial layer 107 and the periodic structure units 103 is easy to cause crystal dissociation, and the mechanical lift-off transfer of the homogeneous epitaxial layer 107 is realized.
step S6 is to peel off the transferred homoepitaxial layer 107 from the semiconductor homosubstrate as shown in fig. 19, thereby achieving the transfer of the homoepitaxial layer 107.
In step S6, the specific method is: the homogeneous epitaxial layer 107 and the semiconductor homogeneous substrate are separated at the position of the outward protruding seed crystal 106 by a vacuum adsorption mechanical stripping method or a wet chemical etching stripping method, so that the transfer of the homogeneous epitaxial layer 107 is realized.
For example, a GaN wafer can be mechanically peeled only by vacuum adsorption because of difficulty in wet etching.
For example, for Si wafers and Ge wafers, alkali etching stripping may be used, and vacuum adsorption mechanical stripping may also be used.
As an example, for GaAs wafers, vacuum adsorption mechanical stripping may be used, and wet etching stripping, for example, etching with H 2 SO 4 + H 2 O 2 + H 2 O, may also be used.
in this embodiment, the semiconductor native substrate after the peeling of the transferred native epitaxial layer 107 is suitable for repeated use in the step S5 of forming the native epitaxial layer. It should be explained that, after the lift-off transfer of the homoepitaxial layer 107 obtained by the homoepitaxial growth is performed, the periodic structure unit 103 is still located on the mother substrate 101, the shape and the epitaxial barrier layer 104 around the periodic structure unit 103 are kept intact, and only the top of the periodic structure unit 103 is exposed with the semiconductor material, i.e., the top of the periodic structure unit 103 still keeps the quality of the outwardly protruding seed crystal 106, so that the remaining structured semiconductor homoepitaxial substrate can be directly recycled after the lift-off transfer of the homoepitaxial layer 107 obtained by the homoepitaxial growth.
in addition, in the embodiment, after the semiconductor homogeneous substrate is repeatedly used for a plurality of times, before the epitaxial barrier layer 104 coated outside each periodic structure unit 103 in the semiconductor homogeneous substrate is peeled and transferred from the semiconductor homogeneous substrate, the epitaxial barrier layer 104 is thickened to restore the reusability of the semiconductor homogeneous substrate, considering that when the semiconductor homogeneous substrate is subjected to homogeneous vapor phase epitaxial growth, a certain amount of erosion and thinning of the epitaxial barrier layer 104 (such as generation of GaO x x x which is easy to evaporate on the surface of SiO 2) can be generated by a vapor phase reactant, after the semiconductor homogeneous substrate is repeatedly used for a certain number of times, the epitaxial barrier layer 104 is thickened by a PE-ALD method before the homogeneous epitaxial layer 107 is peeled and transferred from the semiconductor homogeneous substrate, and the reusability of the semiconductor homogeneous substrate can be further ensured.
and (4) returning the stripped substrate to S5 for reuse after the steps S1-S6, and finally completely realizing the growth and the stripping transfer of the homoepitaxial layer.
As can be seen from the above, the method for preparing a homogeneous epitaxial layer according to the present embodiment directly epitaxially grows a single crystal wafer or a thin film on the basis of the method for preparing a semiconductor homogeneous substrate according to the first embodiment of the present invention, and the thickness is simply controlled by the growth time, thereby avoiding material loss caused by the conventional wafer cutting process and sufficiently utilizing material resources; furthermore, the wafer or the film can be directly peeled and transferred by quick and simple mechanical or chemical etching. In addition, the semiconductor substrate can be reused, and material resources are saved. In addition, the obtained thin wafer or thin film provides stable mechanical support by the periodic structure units with uniform distribution, and the thin wafer or thin film is convenient to carry out various device processing depending on the mother substrate without cracking.
In summary, the semiconductor homogeneous substrate and the preparation method thereof of the present invention have the following beneficial effects:
The semiconductor homogeneous substrate can utilize gas-phase reactants to directly epitaxially grow a single crystal wafer or a film, the thickness is simply controlled by the growth time, the material loss caused by the traditional wafer cutting process is avoided, and the material resources are fully utilized; furthermore, rapid and simple mechanical or chemical etching, peeling and transfer of the grown wafer or film can be performed. In addition, the periodic structure units which are uniformly distributed can provide stable mechanical support for the thin wafer or the thin film which is grown in a subsequent gas phase, and the thin wafer or the thin film can be conveniently processed on the basis of the mother substrate without cracking. In addition, the wafer cleaning agent can be subjected to a traditional wafer cleaning process, is not easy to damage and can be recycled.
The method of the semiconductor homogeneous substrate technology can conveniently utilize the thin wafer or the thin film to realize the processing of flexible and light devices, and further save material resources; moreover, the problems of lattice mismatch and thermal mismatch caused by lack of a single crystal in the GaN-based semiconductor technology are solved fundamentally, a high-crystal-quality GaN wafer or film is obtained, and the design of the device in the aspects of electricity, optics and the like can be more reasonable; in addition, GaAs-based single-junction flexible thin cells with different band gap widths can be conveniently realized, further, mechanical stacking can be carried out to form a multi-junction solar cell, the complex process generated by the traditional epitaxial stacking is avoided, the multi-junction solar cell can be formed by the GaAs-based single-junction flexible thin cells and Ge, Si and GaN series flexible thin cells, more band gap layout freedom is provided for the design of the multi-junction solar cell, the photovoltaic conversion efficiency is improved, and the cost of the multi-junction solar cell is reduced.
According to the preparation method of the homogeneous epitaxial layer, on the basis of the preparation method of the semiconductor homogeneous substrate, the single crystal wafer or the film is directly epitaxially grown, the thickness is simply controlled by the growth time, the material loss caused by the traditional wafer cutting process is avoided, and the material resource is fully utilized; furthermore, the wafer or the film can be directly peeled and transferred by quick and simple mechanical or chemical etching. In addition, the semiconductor substrate can be reused, and material resources are saved. In addition, the obtained thin wafer or thin film provides stable mechanical support by the periodic structure units with uniform distribution, and the thin wafer or thin film is convenient to carry out various device processing depending on the mother substrate without cracking.
Therefore, the invention effectively overcomes various defects in the prior art and has high industrial utilization value.
The foregoing embodiments are merely illustrative of the principles and utilities of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or change the above-mentioned embodiments without departing from the spirit and scope of the present invention. Accordingly, it is intended that all equivalent modifications or changes which can be made by those skilled in the art without departing from the spirit and technical spirit of the present invention be covered by the claims of the present invention.

Claims (12)

1. A method for preparing a semiconductor homogeneous substrate is characterized by at least comprising the following steps:
Providing a mother substrate;
forming a periodic structure at least consisting of a plurality of periodic structure units on the surface of the mother substrate;
Forming an epitaxial barrier layer for realizing selective homoepitaxial growth on the surfaces of the mother substrate and the periodic structure;
correspondingly forming an outward protruding seed crystal at the top of each periodic structure unit, thereby forming a seed crystal array at least consisting of a plurality of outward protruding seed crystals and finally obtaining the semiconductor homogeneous substrate, wherein the specific method comprises the following steps: filling a melt on the epitaxial barrier layer and among the periodic structure units of the periodic structure, and solidifying;
removing the melt solidified substance and the corresponding epitaxial barrier layer on the top of each periodic structure unit of the periodic structure to expose the top of each periodic structure unit of the periodic structure;
Removing the residual melt solidified substances to enable the exposed top of each periodic structure unit to serve as an outward protruding seed crystal and enable the part, covered by the epitaxial barrier layer, of each periodic structure unit to serve as a supporting part of the outward protruding seed crystal, so that a seed crystal array at least comprising a plurality of outward protruding seed crystals is formed, and finally the semiconductor homogeneous substrate is obtained;
and filling a melt on the epitaxial barrier layer and among the periodic structure units of the periodic structure, and solidifying the melt, wherein the specific method comprises the following steps:
Immersing the substrate structure with the epitaxial barrier layer formed in a melt, taking out the substrate structure and placing the substrate structure in an inclined mode, keeping the ambient temperature higher than the melting point of the melt substance, enabling gaps on the epitaxial barrier layer and among all periodic structure units of the periodic structure to be filled with the melt, and enabling redundant melt to automatically flow away from the surface of the substrate structure;
Horizontally placing the substrate structure filled with the melt, keeping the ambient temperature higher than the melting point of the melt substance, and standing to ensure that the melt is uniformly filled among the periodic structure units of the periodic structure;
The substrate structure after standing was cooled to room temperature to solidify the melt.
2. The method for preparing a semiconductor homogeneous substrate according to claim 1, wherein a periodic structure composed of at least a plurality of periodic structure units is formed on the surface of the mother substrate, and the method comprises:
Forming a mask layer with a preset periodic structure pattern on the surface of the mother substrate;
Forming a periodic structure on the mother substrate based on the pattern of the mask layer, wherein the periodic structure at least comprises a plurality of periodic structure units which are arranged in an array and have the same shape;
And removing the mask layer.
3. the method of claim 1, wherein the melt solidified substance and the corresponding epitaxial barrier layer on top of each periodic structure unit of the periodic structure are removed to expose the top of each periodic structure unit of the periodic structure by:
placing the substrate structure after solidifying the melt in a low-solubility solvent to enable the melt solidified substance to be slightly soluble, and removing the melt solidified substance on the top of each periodic structure unit of the periodic structure to expose the epitaxial barrier layer on the top of each periodic structure unit of the periodic structure;
and removing the epitaxial barrier layer on the top of each periodic structure unit of the periodic structure to expose the top of each periodic structure unit of the periodic structure.
4. A method of manufacturing a semiconductor homogeneous substrate according to claim 3, wherein said low solubility solvent is an organic solvent controllable to slowly dissolve and remove melt solidified material on top of each periodic structure unit of said periodic structure.
5. The method for producing a semiconductor homogeneous substrate according to claim 1, wherein in the removing of the remaining melt-solidified substance, the remaining melt-solidified substance is dissolved and removed using a highly soluble solvent which is an organic solvent capable of rapidly dissolving and completely removing the remaining melt-solidified substance.
6. The method for producing a semiconductor homogeneous substrate according to claim 1, wherein the melt is a liquid obtained by melting a hydrophobic organic solid substance having a melting temperature of 300 ℃ or lower and capable of dissolving in an organic solvent.
7. The method for producing a semiconductor homogeneous substrate according to claim 1, wherein a diffusion preventing layer for preventing diffusion of an oxygen element into a semiconductor is further formed between the surface of the mother substrate and the periodic structure and the epitaxial barrier layer; and when the melt solidified substance and the epitaxial barrier layer on the top of each periodic structure unit of the periodic structure are removed, removing the diffusion barrier layer at the corresponding position to expose the top of each periodic structure unit of the periodic structure.
8. The method for producing a semiconductor homogeneous substrate according to claim 1, wherein the periodic structure unit is columnar, stripe-shaped, ribbon-shaped, wavy, pyramidal, or irregular in shape.
9. The method for producing a semiconductor native substrate according to claim 1, wherein the mother substrate is a single crystal wafer or a target semiconductor epitaxial single crystal thin film grown on a hetero single crystal wafer.
10. A preparation method of a homogeneous epitaxial layer is characterized by at least comprising the following steps:
Preparing a semiconductor native substrate by the method for preparing a semiconductor native substrate according to any one of claims 1 to 9;
Forming a homogeneous epitaxial layer on the semiconductor homogeneous substrate, wherein the homogeneous epitaxial layer is an epitaxial single crystal wafer or a film;
Peeling and transferring the homogeneous epitaxial layer from the semiconductor homogeneous substrate;
And the semiconductor homogeneous substrate after the homogeneous epitaxial layer is stripped and transferred is suitable for being repeatedly used in the step of forming the homogeneous epitaxial layer.
11. The method for preparing a homoepitaxial layer according to claim 10, wherein the homoepitaxial layer is formed on the semiconductor homoepitaxial substrate by a specific method comprising:
Selectively performing homoepitaxial growth on the semiconductor homoepitaxial substrate to grow and combine discrete protruded seed crystals in the seed crystal array to form a nonporous continuous epitaxial single crystal wafer or film, thereby obtaining a homoepitaxial layer with the same chemical composition as the protruded seed crystals; and the homogeneous epitaxial layer is connected with the mother substrate through the part of each periodic structure unit of the periodic structure, which is coated by the epitaxial barrier layer.
12. The method for preparing the homogeneous epitaxial layer according to claim 10, wherein after the semiconductor homogeneous substrate is reused for a plurality of times, before the homogeneous epitaxial layer is peeled off from the semiconductor homogeneous substrate and transferred, an epitaxial barrier layer coated outside each periodic structure unit in the semiconductor homogeneous substrate is thickened so as to restore reusability of the semiconductor homogeneous substrate.
CN201611199810.XA 2016-12-22 2016-12-22 Semiconductor homogeneous substrate and preparation method thereof, and preparation method of homogeneous epitaxial layer Active CN108231950B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201611199810.XA CN108231950B (en) 2016-12-22 2016-12-22 Semiconductor homogeneous substrate and preparation method thereof, and preparation method of homogeneous epitaxial layer

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201611199810.XA CN108231950B (en) 2016-12-22 2016-12-22 Semiconductor homogeneous substrate and preparation method thereof, and preparation method of homogeneous epitaxial layer

Publications (2)

Publication Number Publication Date
CN108231950A CN108231950A (en) 2018-06-29
CN108231950B true CN108231950B (en) 2019-12-10

Family

ID=62657146

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201611199810.XA Active CN108231950B (en) 2016-12-22 2016-12-22 Semiconductor homogeneous substrate and preparation method thereof, and preparation method of homogeneous epitaxial layer

Country Status (1)

Country Link
CN (1) CN108231950B (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111235633A (en) * 2020-01-16 2020-06-05 中国科学院半导体研究所 Method for preparing self-supporting silicon carbide wafer on surface of silicon melt through CVD

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN200982977Y (en) * 2006-10-25 2007-11-28 中国科学院大连化学物理研究所 A micro-current control chip for integrated solid phase extraction pole
CN102320555A (en) * 2010-12-07 2012-01-18 东南大学 Single nanometer hole preparation method based on glass micro tube and medium identification method
CN102820379A (en) * 2012-08-28 2012-12-12 天威新能源控股有限公司 Method for preparing solar battery by adopting paraffin wax external-frame masking method
CN104086085A (en) * 2014-06-30 2014-10-08 常州大学 Method for etching regular micro-well array on surface of glass slide
CN104143496A (en) * 2013-05-08 2014-11-12 中国科学院上海高等研究院 Crystalline silicon film manufacturing method based on layer transferring
WO2016136181A1 (en) * 2015-02-27 2016-09-01 Canon Kabushiki Kaisha Patterning method, method for producing processed substrate, method for producing optical component, method for producing circuit board, and method for producing electronic component

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN200982977Y (en) * 2006-10-25 2007-11-28 中国科学院大连化学物理研究所 A micro-current control chip for integrated solid phase extraction pole
CN102320555A (en) * 2010-12-07 2012-01-18 东南大学 Single nanometer hole preparation method based on glass micro tube and medium identification method
CN102820379A (en) * 2012-08-28 2012-12-12 天威新能源控股有限公司 Method for preparing solar battery by adopting paraffin wax external-frame masking method
CN104143496A (en) * 2013-05-08 2014-11-12 中国科学院上海高等研究院 Crystalline silicon film manufacturing method based on layer transferring
CN104086085A (en) * 2014-06-30 2014-10-08 常州大学 Method for etching regular micro-well array on surface of glass slide
WO2016136181A1 (en) * 2015-02-27 2016-09-01 Canon Kabushiki Kaisha Patterning method, method for producing processed substrate, method for producing optical component, method for producing circuit board, and method for producing electronic component

Also Published As

Publication number Publication date
CN108231950A (en) 2018-06-29

Similar Documents

Publication Publication Date Title
US3993533A (en) Method for making semiconductors for solar cells
US10347794B2 (en) Gallium nitride wafer substrate for solid state lighting devices and associated systems
CN111682061B (en) Nitride epitaxial wafer, preparation method thereof and semiconductor device
US5549747A (en) Method of producing sheets of crystalline material and devices made therefrom
US5676752A (en) Method of producing sheets of crystalline material and devices made therefrom
WO2018086380A1 (en) Method for preparing large-sized iii-v heterogeneous substrate
US5588994A (en) Method of producing sheets of crystalline material and devices made therefrom
CN111769036B (en) Preparation method of gallium nitride single crystal substrate
US5273616A (en) Method of producing sheets of crystalline material and devices made therefrom
CN110783169A (en) Preparation method of single crystal substrate
US5328549A (en) Method of producing sheets of crystalline material and devices made therefrom
CN102286777B (en) H3PO4 corrosive seed crystal for growing GaN (Gallium Nitride) single crystal by using HVPE (Hydride Vapor Phase Epitaxial) and preparation method thereof
CN108231950B (en) Semiconductor homogeneous substrate and preparation method thereof, and preparation method of homogeneous epitaxial layer
CN109585615B (en) Method for stripping gallium nitride epitaxial layer from substrate
KR20120029248A (en) A method for fabricating gan wafer
CN103956417A (en) Method for preparing non-polar surface or semi-polar surface single crystal semiconductor self-supporting substrate
CN115881514A (en) Method for manufacturing single crystal self-supporting substrate
JP2015512149A (en) Multilayer metal support
WO2023040237A1 (en) Method for manufacturing self-supporting gallium nitride substrate
US20100102419A1 (en) Epitaxy-Level Packaging (ELP) System
US11661670B2 (en) High quality group-III metal nitride seed crystal and method of making
US20100187572A1 (en) Suspended mono-crystalline structure and method of fabrication from a heteroepitaxial layer
CN105762065B (en) Method for epitaxial growth of nitride with high crystal quality
CN110491973A (en) C surface GaN film and preparation method thereof based on SiC graph substrate
KR20130078984A (en) Method for fabricating gallium nitride substrate

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant