KR102716074B1 - Method And Apparatus for Fabricating Silicon Film Stack Including Porous Silicon - Google Patents

Abstract

According to one embodiment of the present disclosure, a method for manufacturing a silicon laminated structure using a CCP (Capacitively Coupled Plasma) type plasma reactor is provided, comprising: a deposition step of growing a laminated structure including one or more porous silicon layers on a crystalline silicon substrate using a plasma epitaxy method; and a growth control step of controlling the growth of the laminated structure during the deposition step using a silicon thin film phase transition according to process variables of the plasma reactor, wherein the laminated structure is characterized in that, when grown on an upper surface of the crystalline silicon substrate, an epitaxy silicon layer is grown on the upper surface of the crystalline silicon substrate, and a porous silicon layer is grown on the upper surface of the epitaxy silicon layer. A method for manufacturing a silicon laminated structure including porous silicon is provided.

Description

Method and Apparatus for Fabricating Silicon Film Stack Including Porous Silicon

The present disclosure relates to a method for manufacturing a silicon laminate structure including porous silicon and a manufacturing apparatus.

The material described in this section merely provides background information for the present disclosure and does not constitute prior art.

The manufacturing of semiconductor devices involves many types of thin film deposition processes. The deposition process is a method of forming a thin film by vaporizing or sublimating a material to be synthesized in a vacuum and attaching it to the surface of a substrate at the atomic or molecular level. Epitaxy during the deposition process refers to the phenomenon in which a thin film formed under specific conditions grows into the same crystal structure as the substrate. Therefore, if a thin film is deposited on a crystalline silicon substrate by the epitaxy method, a crystalline silicon thin film like the substrate can be grown.

Epitaxy silicon can be grown using various process methods, and among them, the method of epitaxy growth using plasma-enhanced chemical vapor deposition (PECVD) is called plasma epitaxy. Generally, crystalline silicon is grown at a high temperature of 1300℃ or higher, but the plasma epitaxy method has the characteristic of allowing crystalline silicon to grow at a low temperature of about 200℃. When a thin film is grown using the plasma epitaxy method, the microstructure of the thin film often has a porous structure.

In the case of forming porous silicon having a porous structure in a conventional semiconductor device, a wet electroetching method using a hydrofluoric acid (HF) solution is used on the surface of a crystalline silicon substrate. After forming the porous silicon through a wet process, forming gas annealing using hydrogen gas is additionally performed at a high temperature of about 1100° C. to control the pore distribution of the porous silicon.

However, this method can only form porous silicon on the surface of crystalline silicon, and it is difficult to precisely control the size of the pores in the crystalline silicon, so its application is limited.

In addition, since the electroetching and forming gas annealing processes are wet and dry processes, respectively, there is a problem that the process cost increases and wastewater is generated by linking the wet and dry processes.

A method for manufacturing a laminated thin film including porous silicon according to one embodiment can control the porosity of the porous silicon by changing process conditions during growth of the porous silicon using a plasma epitaxy method.

A method for manufacturing a laminated thin film including porous silicon according to one embodiment can perform a forming gas annealing process using hydrogen gas after growing porous silicon in the same equipment.

The problems to be solved by the present invention are not limited to the problems mentioned above, and other problems not mentioned will be clearly understood by those skilled in the art from the description below.

According to one embodiment of the present disclosure for achieving these objects, a method for manufacturing a silicon laminated structure using a CCP (Capacitively Coupled Plasma) type plasma reactor is provided, comprising: a deposition step of growing a laminated structure including one or more porous silicon layers on a crystalline silicon substrate using a plasma epitaxy method; and a growth control step of controlling the growth of the laminated structure during the deposition step using a silicon thin film phase transition according to process variables of the plasma reactor, wherein the laminated structure is characterized in that, when grown on an upper surface of the crystalline silicon substrate, an epitaxy silicon layer is grown on an upper surface of the crystalline silicon substrate, and a porous silicon layer is grown on an upper surface of the epitaxy silicon layer. A method for manufacturing a silicon laminated structure including porous silicon is provided.

According to one embodiment of the present disclosure, a device for manufacturing a silicon laminated structure including a porous silicon layer comprises: a gas inlet for injecting a reaction gas for deposition of the laminated structure; an upper electrode to which a voltage is applied to activate the reaction gas; a substrate support configured to position a crystalline silicon substrate for deposition of the laminated structure; a lower electrode configured to be connected to the substrate support and to transport and support the substrate support; a servo motor connected to the lower electrode and configured to adjust a distance between the upper electrode and the crystalline silicon substrate; and a control unit for controlling growth of the laminated structure by utilizing a phase transition of a silicon thin film according to process variables while growing the laminated structure on the crystalline silicon substrate, wherein the control unit is characterized in that, when the laminated structure is grown on an upper surface of the crystalline silicon substrate, an epitaxy silicon layer is grown on an upper surface of the crystalline silicon substrate, and a porous silicon layer is grown on an upper surface of the epitaxy silicon layer, the device for manufacturing a silicon laminated structure including porous silicon is characterized in that the device controls the process variables so that the epitaxy silicon layer is grown on an upper surface of the crystalline silicon substrate and the porous silicon layer is grown on an upper surface of the epitaxy silicon layer.

As described above, according to the present embodiment, the method for manufacturing a laminated structure thin film including porous silicon has the effect of being able to form porous silicon of various configurations by controlling the porosity during porous silicon growth. In addition, by changing the porosity during porous silicon growth, there is the effect of being able to grow porous silicon at a desired location such as a surface layer, middle layer, or bottom layer of the thin film and control the distribution and density of the pores.

In addition, since porous silicon growth and forming gas annealing using hydrogen gas can be performed on the same equipment, there is an effect of simplifying the process and reducing process costs.

FIG. 1 is a drawing showing one embodiment of a method for manufacturing a silicon laminate structure including porous silicon according to one embodiment of the present disclosure.
FIG. 2 is a drawing showing another embodiment of a method for manufacturing a silicon laminate structure including porous silicon according to one embodiment of the present disclosure.
FIG. 3 is a phase diagram showing the phase transition of a silicon thin film grown according to process variables of a silicon laminate structure including porous silicon according to one embodiment of the present disclosure.
FIG. 4 is a cross-sectional image of a scanning electron microscope showing the porosity distribution that occurs when a silicon laminate structure including porous silicon according to one embodiment of the present disclosure is subjected to forming gas annealing in a hydrogen atmosphere.
FIG. 5 is a drawing showing a manufacturing device for a silicon laminate structure including porous silicon according to one embodiment of the present disclosure.

Hereinafter, some embodiments of the present disclosure will be described in detail using exemplary drawings. When adding reference numerals to components of each drawing, it should be noted that the same components are given the same numerals as much as possible even if they are shown in different drawings. In addition, when describing the present disclosure, if it is determined that a specific description of a related known configuration or function may obscure the gist of the present disclosure, the detailed description thereof will be omitted.

In describing components of embodiments according to the present disclosure, symbols such as first, second, i), ii), a), b), etc. may be used. These symbols are only for distinguishing the components from other components, and the nature or order or sequence of the components is not limited by the symbols. When a part in the specification is said to "include" or "provide" a component, this does not mean that other components are excluded, but rather that other components can be further included, unless explicitly stated otherwise.

FIG. 1 is a drawing showing one embodiment of a method for manufacturing a silicon laminate structure including porous silicon according to one embodiment of the present disclosure.

FIG. 2 is a drawing showing another embodiment of a method for manufacturing a silicon laminate structure including porous silicon according to one embodiment of the present disclosure.

Referring to FIGS. 1 and 2, a silicon laminate structure including porous silicon according to one embodiment of the present disclosure may include all or part of a crystalline silicon substrate (11), a porous silicon layer (13), and an epitaxial silicon layer (12).

A method for manufacturing a silicon laminate structure including porous silicon is a method for forming a silicon laminate structure including one or more porous silicon layers (13) on a crystalline silicon substrate (11). This method may include a step of preparing a crystalline silicon substrate (11), a deposition step of growing a laminate structure including one or more porous silicon layers (13) on one side or both sides of the crystalline silicon substrate (11), and a porosity control step of controlling the porosity of the porous silicon layer.

In the step of preparing a crystalline silicon substrate (11), the crystalline silicon substrate (11) can be prepared by cutting and processing a grown ingot or block using a wire cutting method. The step of cleaning the surface of the crystalline silicon substrate (11) including etching or polishing the crystalline silicon substrate (11) can be included. Etching can be performed as a wet or dry process.

The deposition step for growing a laminated structure including one or more porous silicon layers (13) can be formed by performing a plasma process in which the porous silicon layer (13) and the epitaxial silicon layer (12) are formed by deposition.

The plasma process can be performed using a plasma reactor (3) having a CCP (Capacitively Coupled Plasma) plasma structure. The CCP plasma reactor (3) enables the growth of a thin film having a laminated structure at a silicon substrate temperature of 1000° C. or lower. The plasma reactor (3) having a CCP plasma structure is described in detail in FIG. 5 below.

The present disclosure can control the porosity of the porous silicon layer by controlling process parameters while growing the porous silicon layer (13) using a plasma epitaxy method. In addition, by changing the porosity during the growth of the porous silicon layer (13), the porous silicon layer (13) can be grown at a desired location such as a surface layer, an intermediate layer, or a bottom layer of a laminated structure, and the distribution and density of the pores can be controlled.

The plasma epitaxy method refers to growing crystalline silicon under specific conditions when depositing a silicon thin film using the PECVD method at a substrate temperature of about 200°C. Generally, crystalline silicon is grown at a high temperature of 1300°C or higher, but has the characteristic of being able to grow crystalline silicon even at a low temperature of about 200°C. Crystalline silicon grown using the plasma epitaxy method is referred to as ‘epitaxial silicon’ below.

Plasma epitaxy was reported in the academic world in the mid-2000s, but it was treated as just a part of defects occurring during the solar cell process, and research was mainly conducted in the direction of suppressing it. In addition, when growing epitaxy silicon using the plasma epitaxy method, a porous silicon layer (13) was first formed on the bottom surface of the epitaxy silicon layer (12). That is, since the epitaxy silicon layer (12) is grown on the top surface of the porous silicon layer (13), there was a limitation that the location of the porous silicon layer (13) was only located at the bottom of the laminated structure.

The method according to the present disclosure can deposit a porous silicon layer (13) or an epitaxial silicon layer (12) on one or both sides of a crystalline silicon substrate (11). When the porous silicon layer (13) or the epitaxial silicon layer (12) is deposited on both sides of the crystalline silicon substrate (11), the deposition can be performed simultaneously on both sides or sequentially on one side at a time. Hereinafter, a method for manufacturing a laminated structure including one or more porous silicon layers (13) will be described in detail.

The crystalline silicon substrate (11) is prepared by cleaning the surface in advance by a method including etching or polishing. The etching can be performed by a wet or dry process. In addition, the cleaned crystalline silicon substrate (11) can be permanently attached to the substrate support (33) of the vacuum chamber (30) of the plasma reaction device (3) of the CCP plasma structure and utilized as a component of the reaction device. The temperature of the crystalline silicon substrate (11) can be controlled in the range of 100 to 1000°C. Preferably, the temperature of the crystalline silicon substrate (11) can be controlled in the range of 200 to 450°C.

At this time, the gap between the upper electrode (31) and the crystalline silicon substrate (11), the gas flow rate ratio, pressure, plasma frequency, and power can be set as process variables to be controlled.

By applying voltage to the upper electrode (31) to generate plasma and injecting precursor gas, impurities, etc. into the vacuum chamber (30), a porous silicon layer (13) or an epitaxial silicon layer (12) can be deposited on one side or both sides of a crystalline silicon substrate (11). For example, a porous silicon layer (13) and an epitaxial silicon layer (12) can be sequentially deposited on one side of a crystalline silicon substrate (11), or a porous silicon layer (13) and an epitaxial silicon layer (12) can be sequentially deposited on both sides of the crystalline silicon substrate (11), respectively. A porous silicon layer (13) can be formed on the surface of a crystalline silicon substrate (11) by decomposing a precursor gas in a plasma atmosphere.

The precursor gas can be injected by diluting at least one selected _{from SiH4} , _Si2H6 , _SiCl4 , _SiHCl3 , and _SiF4 in _H2 or He gas, and the impurities can be injected by diluting at least one selected from C, Ge, B, P, Al, As, O, and N. The precursor gas can be _SiH4 , and the dilution ratio of the gas flow rate R=(100* _SiH4 )/( _H2 + _SiH4 ) can be controlled in the range of 0.1 to 100%.

By maintaining the temperature of the crystalline silicon substrate (11) in the range of 200 to 450°C during deposition of the porous silicon layer (13) and the epitaxial silicon layer (12), a material with low defect density can be synthesized.

Referring to FIG. 3, the temperature, pressure, length of the process reaction space, gas flow rate ratio (R), etc. of the crystalline silicon substrate (11) can be adjusted to change the state of the porous silicon layer (13) and the epitaxy silicon layer (12) and control the porosity. At this time, the length of the process reaction space refers to the gap between the upper electrode (31) and the crystalline silicon substrate (11). For example, by reducing the gas flow rate ratio (R), process pressure, and gap between the upper electrode (31) and the crystalline silicon substrate (11) during deposition of the porous silicon layer (13), a low-density porous silicon layer (13) can be formed. When depositing the epitaxy silicon layer (12) and the porous silicon layer (13), a group 4 element such as C or Ge can be added as an impurity together with the precursor gas to produce an alloy structure, or a dopant such as B, P, Al, As can be added to control the electrical conductivity, or a dielectric layer can be produced by adding an impurity such as O or N. Impurities included in the epitaxial silicon layer (12) and the porous silicon layer (13) may be one or two or more selected from among C, Ge, B, P, Al, As, O, and N.

In order to control the impurity content, one or more gases selected from B ₂ H ₆ , B(CH ₃ ) ₃ , BF ₃ , PH ₃ , AsH ₃ , and Al ₂ (CH ₃ ) ₆ may be added. In order to form a dielectric layer, one or more gases selected from N ₂ O, CO ₂ , O ₂ , NH ₃ , and N ₂ may be further added.

The porous silicon layer (13) and the epitaxial silicon layer (12) can be uniformly deposited with a thickness of 50 to 100 nm. The density of the porous silicon layer can be in the range of 1.1 to 2.33 g/cm3. The epitaxial silicon layer (12) and the porous silicon layer (13) can be single crystal silicon thin films.

A layered structure including one or more porous silicon layers (13) can be manufactured into a heterojunction or homojunction semiconductor device structure of various structures by controlling the impurity concentration during growth.

FIG. 3 is a phase diagram showing the phase transition of a silicon thin film grown according to process variables of a silicon laminate structure including porous silicon according to one embodiment of the present disclosure.

Here, P represents the process pressure, d represents the length of the process reaction space, which is the gap between the upper electrode (31) and the crystalline silicon substrate (11). R represents the gas flow rate, which represents the mixing ratio of the raw materials, SiH ₄ and H ₂ gas. It can be confirmed that porous silicon, epitaxial silicon, and amorphous silicon grow depending on the conditions of each process variable.

By controlling the process variables with reference to the graph of Fig. 3, a porous silicon layer (13) can be grown without an epitaxial silicon layer (12). In addition, by controlling the process variables during the process, a porous silicon layer (13) can be grown at a desired location, such as a surface layer, an intermediate layer, or a bottom layer of a laminated structure.

For example, under conditions where the values of P and d are constant, a porous silicon layer (13) can be grown by decreasing the R value. That is, as the value of H ₂ relative to SiH ₄ increases, the amount of Si-H bonds in the thin film increases, allowing a porous silicon layer (13) with a high porosity to be grown.

For example, as in the case of (b) of FIG. 1, a porous silicon layer (13) may be grown directly on the upper surface of a crystalline silicon substrate (11). In addition, as in the case of (c) of FIG. 2, an epitaxial silicon layer (12) may be grown on the upper surface of a crystalline silicon substrate (11), and a porous silicon layer (13) may be grown on the upper surface of the epitaxial silicon layer (12). An epitaxial silicon layer (12) or a porous silicon layer (13) may be further grown on the upper surface of each porous silicon layer (13) or the epitaxial silicon layer (12). That is, a silicon stack structure including one or more porous silicon layers (13) according to one embodiment of the present disclosure is not limited to a specific embodiment and may be grown in various stack structures.

FIG. 4 is a cross-sectional image of a scanning electron microscope showing the porosity distribution that occurs when a silicon laminate structure including porous silicon according to one embodiment of the present disclosure is subjected to forming gas annealing in a hydrogen atmosphere.

Referring to FIG. 4, the present disclosure may further include a heat treatment step of performing a forming gas annealing (or hydrogen heat treatment) process using hydrogen gas in the same plasma reaction device (3) after depositing a silicon laminate structure including one or more porous silicon layers (13) using a plasma reaction device (3) to readjust the porosity of the porous silicon layer (13).

Fig. 4 (a) is an electron microscope image of a laminated structure in which a porous silicon layer (13) is grown on the upper surface of a crystalline silicon substrate (11). Fig. 4 (b) is an electron microscope image showing the change in the porosity of the porous silicon layer when the laminated structure of Fig. 4 (a) is subjected to forming gas annealing (preferably heat treatment in a hydrogen atmosphere). The portion indicated by a circle or an ellipse in Fig. 4 (b) is a nano porous structure.

The deposition and forming gas annealing process of a porous silicon layer (13) can be performed by controlling the distance between electrodes in the same plasma reactor (3). Therefore, there is an effect of simplifying the process and reducing costs.

The present disclosure may further include a step of peeling off the laminated structure manufactured by the above-described method from the crystalline silicon substrate (11) by applying thermal and mechanical stress. A porous silicon thin film can be manufactured by forming a laminated structure including one or more porous silicon layers (13) and then bonding it to a heterogeneous substrate (15) and peeling it off. The heterogeneous substrate (15) can be made of a solid material such as silicon, quartz, plastic, metal foil, glass, and sapphire (Al ₂ O ₃ ).

In the past, due to the structural limitation that the epitaxial silicon layer (12) must be positioned on the upper surface of the laminated structure including the porous silicon layer (13), a separate adhesion-promoting layer was used during the peeling process. An adhesion-promoting layer was laminated on the upper surface of the laminated structure including the porous silicon layer (13), and a heterogeneous substrate (15) was bonded on the adhesion-promoting layer to peel the laminated structure.

On the other hand, since the present disclosure can grow a porous silicon layer (13) on the upper surface of a laminated structure, a heterogeneous substrate (15) can be directly bonded to the laminated structure without a separate adhesion promoting layer. In other words, since there is no separate adhesion promoting layer, the process cost is reduced, and a laminated structure including a porous silicon layer (13) can be manufactured.

For example, referring to (c) and (d) of FIG. 1, a process of peeling off a crystalline silicon substrate (11) from a laminated structure including a crystalline silicon substrate (11), a porous silicon layer (13), and a heterogeneous substrate (15) can be confirmed. Referring to (d) and (e) of FIG. 2, a process of peeling off a crystalline silicon substrate (11) from a laminated structure including a crystalline silicon substrate (11), an epitaxial silicon layer (12), a porous silicon layer (13), and a heterogeneous substrate (15) can be confirmed.

The laminated structure including the porous silicon layer (13) can be easily peeled off from the crystalline silicon substrate (11) by the porous silicon layer (13). The porous silicon layer (13) is bonded to the crystalline silicon substrate (11) in a part of its area, not the entire area, due to the pores. In other words, the adhesive force between the porous silicon layer (13) and the crystalline silicon substrate (11) is weak, so that easy peeling is possible.

The crystalline silicon substrate (11) from which the laminated structure including the porous silicon layer (13) is peeled off can be recycled for the next process for forming the same laminated structure thin film after an appropriate surface cleaning process. Therefore, the crystalline silicon substrate (11) does not lose material even after the growth and peeling processes of the porous silicon layer (13). As a result, the crystalline silicon substrate (11) can be attached to the substrate support (33) and used as a permanent component of the reactor.

Methods for bonding a heterogeneous substrate (15) to a laminated structure including a porous silicon layer (13) can include anodic bonding, fusion bonding, metal electrodeposition, and epoxy adhesion.

The method for manufacturing a laminated structure including a porous silicon layer (13) can implement a laminated structure thin film having a thickness of 1000 ㎛ or less by controlling the deposition thickness. In addition, since the thin film is directly deposited on a crystalline silicon substrate (11), the process steps can be shortened, and since the thin film can be formed at a substrate temperature of 1000 ℃ or less, there is an advantage in that the process cost is reduced, thereby enabling commercialization. The method for manufacturing a laminated structure including a porous silicon layer (13) can also be applied to the manufacture of semiconductor devices including solar cells.

FIG. 5 is a drawing showing a manufacturing device for a silicon laminate structure including porous silicon according to one embodiment of the present disclosure.

A plasma reactor (3) of a CCP plasma structure may include all or part of a vacuum chamber (chamber, 30), an upper electrode (31), a lower electrode (32), and a control unit. The upper electrode (31) and the lower electrode (32) may be positioned within the vacuum chamber (30). At this time, the upper electrode (31) may be manufactured in a form in which a gas inlet (or showerhead, 31a) is coupled to the upper electrode (31). The substrate support (33) is attached to the lower electrode (32), and the upper electrode (31) may be positioned to have a predetermined electrode distance from the lower electrode (32). In addition, a crystalline silicon substrate (11) may be attached to the substrate support (33) and used as a permanent component of the reactor. The lower electrode (32) may be configured to be grounded and to be connected to a power source (35) to apply voltage to the upper electrode (31). At this time, plasma frequencies such as 13.56 MHz, 27.12 MHz, 40.68 MHz, 54.24 MHz, and 60 MHz can be used.

As described above, the control unit can control the process variables during the process to grow the epitaxial silicon layer (12) or the porous silicon layer (13). The control unit can control the process variables during the process to grow the porous silicon layer (13) at a desired location, such as a surface layer, an intermediate layer, or a bottom layer of a laminated structure. The control unit can control the porosity of the porous silicon layer (13) by controlling the process variables after the deposition of the porous silicon layer (13) is completed or at any point during the deposition.

The plasma reactor (3) of the CCP plasma structure injects gas into the vacuum chamber (30) using the upper electrode (31) and applies voltage (35) to the upper electrode (31), and plasma is generated and maintained by glow discharge, and the plasma decomposes the precursor gas and deposits it on the crystalline silicon substrate (11).

The substrate support (33) can transport and support the crystalline silicon substrate (11). The substrate support (33) can be attached to the upper surface of the lower electrode (32). A heater for temperature control can be built into the lower part of the substrate support (33), and the substrate support (33) can be designed so that individual temperature control is possible for each section. The substrate support (33) can be made of a material such as graphite that does not deform under high temperature and plasma atmosphere. In addition, the crystalline silicon substrate (11) can be attached to the substrate support (33) and used as a permanent component of the reactor.

A servomotor (34) may be attached to the lower electrode (32). The servomotor (34) can move the lower electrode (32) in the vertical direction to adjust the distance between the upper electrode (31) and the lower electrode (32). By adjusting the distance between the electrodes in one plasma reactor (3), the deposition and forming gas annealing process of the porous silicon layer (13) can be performed. Therefore, there is an effect of simplifying the process and reducing the cost. For example, in the low-temperature deposition step, the distance between the upper electrode (31) and the lower electrode (32) can be 0.5 cm to 3 cm, and in the forming gas annealing step, the distance between the upper electrode (31) and the lower electrode (32) can be increased to create a distance of 10 cm or more.

The plasma reactor (3) of the CCP plasma structure can change process variables by controlling the distance between the upper electrode (31) and the lower electrode (32) and thereby controlling the distance between the crystalline silicon substrate (11) and the plasma electrode. For example, by controlling the distance between the upper electrode (31) and the lower electrode (32), all or part of the porous silicon layer (13) and the epitaxial silicon layer (12) can be grown on the upper surface of the crystalline silicon substrate (11). In addition, as described above, the porosity of the porous silicon layer (13) can be controlled by controlling the process variables. At this time, the distance between the upper electrode (31) and the lower electrode (32) can be controlled with reference to the graph of FIG. 3.

The plasma reactor (3) of the CCP plasma structure enables a uniform plasma process and can obtain an excellent thin film even at a low temperature of 1000°C or less for the silicon substrate temperature.

The above description is merely an illustrative description of the technical idea of the present embodiment, and those with ordinary skill in the art to which the present embodiment pertains may make various modifications and variations without departing from the essential characteristics of the present embodiment. Therefore, the present embodiments are not intended to limit the technical idea of the present embodiment but to explain it, and the scope of the technical idea of the present embodiment is not limited by these embodiments. The protection scope of the present embodiment should be interpreted by the following claims, and all technical ideas within a scope equivalent thereto should be interpreted as being included in the scope of the rights of the present embodiment.

11: Crystalline silicon substrate 12: Epitaxial silicon layer
13: Porous silicon layer 15: Heterogeneous substrate
3: Plasma reactor with CCP plasma structure 30: Vacuum chamber
31: Upper electrode 31a: Shower head
32: Lower electrode 33: Substrate support
34: Servo motor

Claims (21)

In a method for manufacturing a silicon laminate structure using a plasma reaction device of the CCP (Capacitively Coupled Plasma) method,
A deposition step of growing a layered structure including one or more porous silicon layers on a crystalline silicon substrate using a plasma epitaxy method; and
Including a growth control step for controlling the growth of the laminated structure during the deposition step by using the phase change of the silicon thin film according to the process variables of the plasma reaction device,
The above laminated structure is,
A method for manufacturing a silicon laminate structure including porous silicon, characterized in that when grown on the upper surface of the above crystalline silicon substrate, an epitaxial silicon layer is grown on the upper surface of the above crystalline silicon substrate, and a porous silicon layer is grown on the upper surface of the epitaxial silicon layer. In the first paragraph,
The above deposition step is,
A method for manufacturing a _silicon multilayer structure including porous _silicon , characterized in that the porous silicon layer or the epitaxial silicon layer is grown by controlling one or more variables selected from temperature, plasma power, process pressure, length of process reaction space, and mixing ratio of SiH 4 gas and H 2 gas. In the first paragraph,
The above growth control steps are:
A method for manufacturing a silicon laminate structure including porous silicon, characterized in that it includes a porosity control step for controlling the porosity of the porous silicon layer by controlling the process variables during the deposition step. In the third paragraph,
The above process variables are,
Including one or more variables selected from temperature, plasma power, process pressure, length of process reaction space, and mixing ratio of SiH ₄ gas and H ₂ gas,
A method for manufacturing a silicon laminate structure including porous silicon, characterized in that the length of the above-mentioned process reaction space is the distance between the above-mentioned crystalline silicon substrate and the plasma electrode. In the fourth paragraph,
The above porosity control step is,
A method for manufacturing a silicon laminate structure including porous silicon, characterized in that the porosity of the porous silicon layer is increased by increasing the ratio of the H ₂ gas to the SiH ₄ gas. In the first paragraph,
A method for manufacturing a silicon laminate structure including porous silicon, characterized in that it further includes a heat treatment step of readjusting the porosity of the porous silicon layer using forming gas annealing. In Article 6,
The above deposition step and the above heat treatment step,
A method for manufacturing a silicon laminate structure including porous silicon, characterized in that the method is performed in a plasma reaction device of a CCP (Capacitively Coupled Plasma) type. In Article 6,
The above deposition step and the above heat treatment step,
1000

A method for manufacturing a silicon laminate structure including porous silicon, characterized in that it is performed at a temperature below. In clause 1 or clause 6,
A method for manufacturing a silicon laminate structure including porous silicon, characterized in that it further includes a peeling step of peeling the laminate structure including one or more porous silicon layers from the crystalline silicon substrate. In Article 9,
A method for manufacturing a silicon laminate structure including porous silicon, characterized in that it further includes a step of bonding a heterogeneous substrate made of at least one material selected from silicon, quartz, sapphire, glass, plastic, and metal foil to an upper surface of a laminate structure including at least one porous silicon layer. In Article 10,
The step of bonding the above heterogeneous substrates is:
A method for manufacturing a silicon laminate structure including porous silicon, characterized by using at least one method selected from anodic bonding, fusion bonding, metal electrodeposition, and epoxy adhesion. In a silicon laminate structure manufacturing device including a porous silicon layer,
A gas inlet for injecting a reaction gas for deposition of the above-mentioned laminated structure;
An upper electrode to which voltage is applied to activate the above reaction gas;
A substrate support configured to position a crystalline silicon substrate for deposition of the above-described laminated structure;
A lower electrode configured to be joined to the substrate support and to transport and support the substrate support;
A servo motor connected to the lower electrode and configured to adjust the distance between the upper electrode and the crystalline silicon substrate; and
Including a control unit that controls the growth of the laminated structure by utilizing the phase change of the silicon thin film according to the process variables while growing the laminated structure on the crystalline silicon substrate.
The above control unit,
A device for manufacturing a silicon laminate structure including porous silicon, characterized in that the process variables are controlled so that, when the laminate structure is grown on the upper surface of the crystalline silicon substrate, an epitaxial silicon layer is grown on the upper surface of the crystalline silicon substrate, and a porous silicon layer is grown on the upper surface of the epitaxial silicon layer. In Article 12,
The above process variables are,
Including one or more variables selected from temperature, plasma power, process pressure, length of process reaction space, and mixing ratio of SiH ₄ gas and H ₂ gas,
A silicon laminate structure manufacturing device including porous silicon, characterized in that the length of the above process reaction space is the distance between the upper electrode and the crystalline silicon substrate. In Article 12,
The above control unit,
A device for manufacturing a silicon laminate structure including porous silicon, characterized in that the porosity of the porous silicon layer is controlled by controlling process variables after the deposition of the porous silicon layer is completed or at any time during the deposition. In Article 12,
The above control unit,
A device for manufacturing a silicon laminate structure including porous silicon, characterized in that the distance between the upper electrode and the lower electrode is controlled by controlling the process variables during the above-described laminate structure deposition step and the heat treatment step for readjusting the porosity of the porous silicon layer. In Article 12,
The above control unit,
Including porous silicon, characterized in that the servo motor is driven and controlled so that the distance between the upper electrode and the lower electrode is adjusted to 0.5 cm to 3 cm during the deposition step,
The above deposition step is,
A silicon multilayer structure manufacturing device, which is a step of growing a multilayer structure including one or more porous silicon layers on the above crystalline silicon substrate using a plasma epitaxy method. In Article 12,
The above control unit,
Including porous silicon characterized in that the servo motor is driven and controlled so that the distance between the upper electrode and the lower electrode is adjusted to 10 cm or more during the heat treatment step,
The above heat treatment step is,
A device for manufacturing a silicon laminated structure, the device being a step of readjusting the porosity of the porous silicon layer using forming gas annealing. In Article 12,
The above substrate support is,
A silicon laminate structure manufacturing device comprising porous silicon, characterized in that the silicon laminate structure is composed of graphite and a heater for temperature control is built into the lower part of the substrate support. In Article 12,
The above crystalline silicon substrate,
A silicon laminate structure manufacturing device including porous silicon, characterized in that it is permanently attached to the above substrate support and is utilized as a component in a silicon laminate structure manufacturing device including the porous silicon. In a method for manufacturing a silicon laminate structure using a plasma reaction device of the CCP (Capacitively Coupled Plasma) method,
A deposition step of growing a layered structure including one or more porous silicon layers on a crystalline silicon substrate using a plasma epitaxy method; and
Including a growth control step for controlling the growth of the laminated structure during the deposition step by using the phase change of the silicon thin film according to the process variables of the plasma reaction device,
The above laminated structure is,
A method for manufacturing a silicon laminate structure including porous silicon, characterized in that when grown on the lower surface of the above crystalline silicon substrate, an epitaxial silicon layer is grown on the lower surface of the above crystalline silicon substrate, and a porous silicon layer is grown on the lower surface of the epitaxial silicon layer. In a method for manufacturing a silicon laminate structure using a plasma reaction device of the CCP (Capacitively Coupled Plasma) method,
A deposition step of growing a layered structure including one or more porous silicon layers on a crystalline silicon substrate using a plasma epitaxy method; and
Including a growth control step for controlling the growth of the laminated structure during the deposition step by using the phase change of the silicon thin film according to the process variables of the plasma reaction device,
The above laminated structure is,
A method for manufacturing a silicon laminate structure including a porous silicon layer, characterized in that when grown on both sides of the crystalline silicon substrate, an epitaxial silicon layer is grown on each side of the crystalline silicon substrate, and a porous silicon layer is grown on each of the upper and lower outer surfaces of the epitaxial silicon layer.

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