WO2024027294A1 - Hot wire chemical vapor deposition apparatus, silicon-based thin film deposition method and solar cell - Google Patents

Abstract

The present invention relates to the technical field of solar cell processing. Disclosed are a hot wire chemical vapor deposition (HWCVD) apparatus, a silicon-based thin film deposition method and a solar cell, which are used for solving the problems of high energy consumption, a low process gas utilization rate and poor film-formation uniformity existing in a PECVD method, and are also used for solving the problems of a complex structure and hot wire sagging existing in a horizontal HWCVD apparatus. The HWCVD apparatus comprises a gas supply device, a vacuum cavity, a gas distribution plate, an insulating bearing member, a hot wire, binding posts, a power supply and a carrier plate, wherein the hot wire has a first end and a second end, which are opposite each other, and both the first end and the second end are electrically connected to the binding posts horizontally arranged. The end of each binding post that connects to the hot wire can provide an elastic pull for the hot wire, so as to tension the hot wire when same is heated to deform. Thus, the hot wire is always in a horizontal state.

Description

Hot filament chemical vapor deposition equipment, silicon-based thin film deposition methods and solar cells

This application requires the priority of the Chinese patent application submitted to the China Patent Office on August 1, 2022, with the application number 202210916701.4 and the invention name "Hot Filament Chemical Vapor Deposition Equipment, Silicon-based Thin Film Deposition Method and Solar Cell", all of which The contents are incorporated into this application by reference.

Technical field

The invention relates to the technical field of solar cell processing, and in particular to a hot filament chemical vapor deposition equipment, a silicon-based thin film deposition method and a solar cell.

Background technique

In the solar cell manufacturing process, plasma enhanced chemical vapor deposition (PECVD) or hot wire chemical vapor deposition (HWCVD) is generally used. Specifically, the HWCVD method can be used to deposit a silicon-based film on the surface of the silicon wafer after texturing and cleaning, or the HWCVD method can be used to form a doped silicon-based film.

Among them, PECVD uses radio frequency power to provide energy to decompose process gases to form plasma, and then form a film on the surface of the silicon wafer. In the above process, the dissociation efficiency of some gas molecules with large bond energy, such as hydrogen, methane, etc., is low. Therefore, ultra-high power supply and large amounts of hydrogen are required to prepare microcrystalline silicon films with excellent photoelectric properties. At this time, there are problems such as low utilization rate of process gas, high cost and poor uniformity.

HWCVD uses a hot wire to catalytically decompose process gases at high temperatures to form a film on the surface of the silicon wafer. It has a high decomposition efficiency for most gases and effectively solves the problem of large process gas consumption in PECVD. However, since the temperature of the hot wire during the HWCVD reaction is as high as 1800-2300°C, the hot wire is easily softened, and gravity will cause the hot wire to deform and sag. Therefore, traditional HWCVD equipment generally has a vertical structure, that is, the hot wire is vertical. Direct installation. However, this structure requires magnetic buckles or covers to vertically fix the substrate, which results in the substrate being inevitably blocked and the blocked parts unable to be coated.

In order to solve the problems of vertical structure HWCVD equipment, the existing technology also provides a horizontal structure HWCVD equipment, that is, the hot wire is installed horizontally. At this time, the substrate can be placed horizontally on the support. On the stage. Based on this, the problem of being unable to coat due to occlusion can be effectively solved. However, the existing horizontal structure HWCVD equipment has problems such as complex structure and sagging of the hot wire when heated.

Contents of the invention

The purpose of the present invention is to provide a hot filament chemical vapor deposition equipment, a silicon-based thin film deposition method and a solar cell to solve the problems of high energy consumption, low process gas utilization and poor film formation uniformity of the PECVD method, while also solving Horizontal HWCVD equipment has problems with complex structure and drooping hot wires.

In a first aspect, the present invention provides a hot wire chemical vapor deposition equipment, including a gas supply device, a vacuum chamber, a gas distribution plate, an insulating support, a hot wire, a terminal, a power supply and a carrier board. The vacuum chamber has an air inlet and an exhaust port. The air supply device supplies reaction gas into the vacuum chamber through the air inlet, and the exhaust gas is discharged from the vacuum chamber through the exhaust port. The air distribution plate is horizontally accommodated in the vacuum chamber and is fastened close to the top of the vacuum chamber. The gas distribution plate has a gas distribution area and an installation area. A gas distribution through hole is provided in the gas distribution area. The reaction gas after entering the vacuum chamber is sprayed to the lower area of the vacuum chamber through the gas distribution through hole. The installation area consists of multiple rows of installation parts. Each row of mounting parts is provided with multiple insulating supports at intervals, and the multiple insulating supports located in the same row jointly carry the heating wire extending in the horizontal direction. The hot wire has a first end and a second end opposite to each other, and both the first end and the second end are electrically connected to the horizontally arranged binding posts. One end of each binding post connected to the hot wire can provide elastic pulling force to the hot wire, so that the hot wire can be tightened when the hot wire is heated and deformed. At this time, the hot wire is always in a horizontal state. Multiple rows of hot wires are connected in series with the power supply. The carrier plate is placed horizontally in the vacuum chamber and below the hot wire to carry the silicon wafer.

Compared with the existing technology, in practical applications, the hot wire vapor deposition equipment provided by the present invention is better than the plasma enhanced chemical vapor deposition method because the above equipment forms a film on the surface of the silicon wafer through the high temperature catalytic decomposition of the reaction gas by the hot wire. Therefore, the decomposition efficiency of most reaction gases is much higher than that of PECVD. Based on this, the problems of large consumption of reaction gases and low decomposition efficiency can be effectively solved. Moreover, since the hot wire vapor deposition equipment provided by the present invention has a horizontal structure, compared with the vertical structure, it can completely solve the problem of vertical fixation of the silicon wafer due to occlusion without the need to use magnetic buckles or covers to vertically fix the silicon wafers. The problem of not being able to coat. More importantly, on the one hand, when the horizontally laid hot wires tend to sag or sag due to high-temperature deformation, multiple insulating supports provided corresponding to each hot wire can provide upward support for the hot wires. , Based on this, the risk of hot wire sagging can be effectively reduced. Secondly, when the horizontally laid hot wires tend to sag or sag due to high temperature deformation, the terminals corresponding to the first and second ends of each hot wire can be adjusted according to the degree of sagging of the hot wires. Adaptable to provide elastic tension. Based on this, you can ensure that the hot wire is always horizontal. always The distance between the horizontal hot wire and the silicon wafer placed on the carrier plate always remains constant. Based on this, the consistency of the film thickness can be ensured, thereby improving the quality of the final solar cell.

In addition, an installation area is set on the air distribution board, and then multiple rows of installation parts provided on the installation area and multiple insulating supports arranged at intervals on the installation parts are used to directly connect the hot wire to the air distribution board. Together. In other words, the gas distribution plate not only has the function of spraying the reaction gas on the surface of the silicon wafer, but also has the function of carrying the hot wire. That is, the gas distribution plate and the hot wire form an "integrated structure" as a whole, which simplifies the chemical vapor phase of the hot wire. deposition equipment, reducing costs.

As a possible implementation manner, each row of mounting parts includes a plurality of first mounting holes opened at intervals. Based on this, the insulating supporting member can be inserted and fixed in the first installation hole to achieve horizontal lifting of the hot wire. It has the advantages of simple structure and convenient installation.

As a possible implementation method, each row of mounting parts is a mounting groove that runs from the beginning of the row to the end of the row. Based on this, the position of the insulating support member can be adjusted in the installation groove according to actual needs (the spacing between the actual array-distributed silicon wafers) (that is, the spacing between two adjacent insulating support members is adjusted), In order to adapt to the different requirements for the position of the insulating support member of silicon wafers of different specifications (or with different spacing). In other words, the applicable scope of the hot filament chemical vapor deposition equipment provided by the present invention can be expanded.

As a possible implementation manner, when multiple silicon wafers are placed horizontally in an array on the carrier board, each row of silicon wafers corresponds to a row of mounting portions above the silicon wafers. At this time, there are gaps between any two adjacent silicon wafers located in the same row, and an insulating support member is provided above each gap.

When the above technical solution is adopted, the insulating support is located above the gap between any two adjacent silicon wafers. At this time, the insulating support will not block the film-forming area of the silicon wafer. Based on this , which can effectively avoid the problem of failure to form film or uneven film formation due to the film formation area of the silicon wafer being blocked.

As a possible implementation manner, the insulating support member is a holding rod, and the holding rod includes a connecting section and a load-bearing section connected with the connecting section. In the assembled state, the connecting section and the installation part are tightly connected, and the load-bearing section is suspended. A load-bearing hole is provided through the load-bearing section along the length direction of the hot wire. The diameters of the load-bearing holes located on the load-bearing sections in the same row are equal and the central axes are collinear. The bore diameters of the load-bearing holes located in different rows are equal and the central axes are coplanar.

With this arrangement, when the multiple hot wires are assembled, the multiple hot wires are coplanar, and the vertical distance between each hot wire and the silicon chip placed on the carrier board is equal. Based on this, within one film formation cycle, and when the concentration of reactive gases sprayed by the gas distribution plate onto the surfaces of different silicon wafers and the gas supply speed are basically the same, the film thicknesses on different silicon wafers can be basically consistent. Based on this, while improving the quality of silicon wafer film formation, the quality of solar cells can be further optimized.

As a possible implementation, the heating wire has a diameter R ₁ , the bearing hole has a diameter R ₂ , and 2R ₁ ≤ R ₂ ≤ 5R ₁ .

When the above technical solution is adopted, since the diameter of the hot wire is smaller than the aperture of the load-bearing hole, it is easier for the hot wire to be inserted into the assembly hole during the assembly process. Based on this, the efficiency of assembly can be improved. After the assembly is completed, that is, when the hot wire passes through the load-bearing hole and is supported by the hole wall of the load-bearing hole, the contact area between the hot wire and the load-bearing hole is relatively small. In other words, the area where the hole wall of the load-bearing hole covers the hot wire is relatively small. At this time, the wire section of the hot wire in contact with the load-bearing hole has a larger heat conduction channel. Based on this, each wire segment of the same hot wire (wholly can be divided into a contact segment in contact with the load-bearing hole and a suspended segment located between two adjacent load-bearing holes and at the opposite first and second ends of the hot wire) radiates radiation The temperature on the silicon wafer is basically the same, so that each area of the same silicon wafer can form a film with a consistent thickness.

As a possible implementation method, the central axis of each hot wire is collinear with the central axis of the terminals provided at both ends of the hot wire. With this arrangement, when the hot wire has a tendency to sag or sag due to high-temperature deformation, the terminals respectively arranged at the first end and the second end of the hot wire provide relative elastic pulling force to both ends of the hot wire that is basically in line with the central axis of the hot wire. collinear. In other words, the elastic pulling force has no component force in other directions in the extension direction of the length of the hot wire. That is, the elastic pulling force provided by the terminal to both ends of the hot wire can basically be used to extend the length of the hot wire. At this time, in order to quickly straighten the hot wire that has a tendency to sag or droop, the hot wire can always be in a horizontal state during use.

As a possible implementation manner, the hot filament chemical vapor deposition equipment further includes two carriers, and the two carriers are spaced apart on both sides of the gas distribution plate along the extension direction of the hot wire. Second mounting holes are spaced on each carrier frame in a direction perpendicular to the extending direction of the hot wire. The terminal posts are assembled in the second mounting holes in a transition or interference fit manner. At this time, each terminal post is collinear with the central axis of the second mounting hole with which it is assembled.

As a possible implementation, each terminal includes a fixing bolt, a first terminal, an elastic member and a second terminal. The fixing bolt has an opposite first end and a second end, facing from the end of the first end to A first receiving groove is opened in the direction close to the second end, and a second receiving groove is opened in the direction close to the first end from the end surface of the second end. The first connection terminal is detachably fastened in the first receiving groove, and the first connection terminal is used for connecting wires or power supply. The elastic member is accommodated in the second receiving groove, and one end of the elastic member is tightly connected to the bottom of the second receiving groove, and the other end is suspended. At least a part of the second connection terminal is accommodated in the second receiving groove, and one end of the second connection terminal is tightly connected to the suspended end of the elastic member, and the other end is connected to the hot wire. The elastic member provides an elastic pulling force for the second connection terminal. When the hot wire pulls the second connection terminal outward, the elastic member applies an elastic pulling force to the second connection terminal to pull the hot wire in a direction close to the bottom of the second receiving groove.

When the above technical solution is adopted, the terminal block is composed of a fixing bolt, a first terminal block, an elastic member and a second terminal block, and has the characteristics of simple and compact structure. In practical applications, when the hot wire deforms at high temperature and has a tendency to sag, the hot wire with a tendency to sag will exert an outward pulling force on the elastic component. Since the elastic component has the property of rebound, the elastic component has When the rebound force is greater than the pulling force exerted by the hot wire on the elastic member, the hot wire with a tendency to sag is pulled to a horizontal state by the elastic member again. Moreover, under the action of the rebound force (i.e., the elastic tension defined above), the second terminal moves in the second receiving groove in a direction close to the bottom of the groove, that is, the second terminal is initially assembled in the second receiving groove. The moving direction is defined to be consistent with the extension direction of the hot wire. Based on this, when the hot wire is deformed at high temperature and has a tendency to sag (at this time, it does not really sag), the hot wire can be flattened in time under the action of the elastic member's resilience. At this time, it can be ensured that the hot wire is always in a horizontal state during use, instead of being in a drooping state for a short moment and then being pulled to a horizontal state.

As a possible implementation manner, the fixing bolt includes a conductive fixing bolt body and an insulating layer disposed on the outer surface of the conductive fixing bolt body. The first receiving groove and the second receiving groove are opened on the conductive fixing bolt body.

As a possible implementation method, a wiring groove is opened from an end of the second wiring terminal away from the elastic member to the side opposite to it, and in the assembled state, the hot wire is inserted into the wiring groove. Each terminal post also includes a locking piece, which is inserted radially from the fixing bolt and pressed onto the hot wire located in the wiring slot.

When the above technical solution is adopted, during the assembly process, the hot wire can be inserted into the wiring trough, and then the locking piece is used to lock the hot wire in the wiring trough, which has the advantages of simple assembly method and high assembly efficiency. When it is necessary to disassemble the hot wire from the second terminal, the locking member can be removed first, and then the hot wire can be pulled out from the wiring slot, which has the advantage of easy disassembly.

As a possible implementation manner, at least one set of releasable spring buckles is provided on the groove wall of the first receiving groove and along the depth direction of the groove. After the first terminal is inserted into the first receiving groove, at least one set of releasable spring buckles is provided for to fix the first terminal. With this arrangement, after the assembly is completed, at least one set of releasable spring buckles can provide a clamping force for the first terminal, so that the axial movement and rotation of the first terminal in the first receiving groove are restricted. Based on this, the assembly stability of the first terminal in the first receiving groove can be improved.

In a second aspect, the present invention also provides a silicon-based thin film deposition method. The silicon-based thin film deposition method applies the hot filament chemical vapor deposition equipment provided by the first aspect and/or any implementation of the first aspect. The silicon-based thin film deposition method Includes the following steps:

Provide at least one silicon wafer, and place the silicon wafer horizontally on the carrier;

At the first moment t ₁ , the gas supply device is controlled to supply reaction gas into the vacuum chamber through the air inlet, and the reaction gas is sprayed to the upper surface of the silicon wafer through the gas distribution plate; where the reaction gas is determined according to the silicon-based film; at the same time, Control the exhaust port to be open;

At the second time t ₂ , the control power supply supplies power to the hot wire to heat the hot wire to the preset temperature, t ₂ -t ₁ >0s; at this time, the reaction gas is separated into atoms on the surface of the hot wire, and the atoms and the silicon wafer The silicon dangling bonds on the surface are bonded to form a silicon-based film on the surface of the silicon wafer; during the process of heating the hot wire to the preset temperature and maintaining the hot wire at the preset temperature, when the hot wire has a tendency to sag due to high deformation, The supporting member and the terminal provide supporting force and elastic tension for the hot wire respectively, so that the hot wire is always in a horizontal state.

Compared with the existing technology, the beneficial effects of the silicon-based thin film deposition method provided by the present invention are the same as those of the first aspect and/or the hot filament chemical vapor deposition equipment provided by any implementation of the first aspect, and are not discussed here. To elaborate.

In a third aspect, the present invention also provides a solar cell. The solar cell sheet is processed and formed by using the hot wire chemical vapor deposition equipment provided by the first aspect and/or any implementation of the first aspect. Or, the solar cells are formed using the silicon-based thin film deposition method provided in the second aspect.

Compared with the prior art, the beneficial effects of the solar cell provided by the present invention are the same as those of the hot filament chemical vapor deposition equipment provided by the first aspect and/or any implementation of the first aspect, and will not be described again here.

Description of the drawings

The drawings described here are used to provide a further understanding of the present invention and constitute a part of the present invention. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the attached picture:

Figure 1 is a schematic diagram of the hot filament chemical vapor deposition method;

Figure 2 is a schematic structural diagram of a hot filament chemical vapor deposition equipment provided by an embodiment of the present invention;

Figure 3 is a bottom view of the air distribution panel provided by the embodiment of the present invention;

Figure 4 is a bottom view of the integrated structure of the air distribution plate and the hot wire provided by the embodiment of the present invention;

Figure 5 is a schematic diagram of hot wire wiring provided by an embodiment of the present invention;

Figures 6 to 9 are schematic structural views of the insulating support provided by embodiments of the present invention;

Figure 10 is an exploded view of the terminal provided by the embodiment of the present invention;

Figure 11 is a cross-sectional view along line A-A of Figure 10;

Figure 12 is a BB-direction cross-sectional view of Figure 10;

FIG. 13 is a cross-sectional view taken along line C-C in FIG. 10 .

Reference signs:
10-hot wire, 11-initial molecule I, 12-initial molecule II;
110-Active ion I, 120-Active ion II, 13-Substrate,
14-film;
20-gas distribution plate, 21-insulation support, 22-heating wire,
23-binding post, 24-power supply, 25-carrier board,
26-Silicon chip, 27-Wire;
200-gas distribution area, 201-installation area, 2010-installation department,
20100-First mounting hole;
210-Connecting section, 211-Loading section, 212-Loading hole,
213-threaded hole;
230-fixing bolt, 2300-first receiving groove, 2301-second receiving groove,
231-first terminal, 232-second terminal, 233-elastic member,
234-locking piece, 235-releasable spring buckle.

Specific embodiments

In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention clearer, the present invention will be further described in detail below with reference to the drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present invention and are not intended to limit the present invention.

It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

In addition, the terms “first” and “second” are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of indicated technical features. Therefore, features defined as "first" and "second" may explicitly or implicitly include one or more of these features. In the description of the present invention, "plurality" means two or more than two, unless otherwise explicitly and specifically limited. "Several" means one or more than one, unless otherwise expressly and specifically limited.

In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "upper", "lower", "front", "back", "left", "right", etc. are based on those shown in the accompanying drawings. The orientation or positional relationship is only for the convenience of describing the present invention and simplifying the description. It does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention.

In the description of the present invention, it should be noted that, unless otherwise clearly stated and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense. For example, it can be a fixed connection or a detachable connection. Connection, or integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be an internal connection between two elements or an interaction between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

Referring to Figure 1, the working principle of HWCVD is to heat a metal wire (which can be defined as a hot wire 10) placed in a reaction chamber (generally a vacuum chamber) to a preset temperature. The preset temperature can be determined based on the reaction gas. Specifically Determined based on the thermal decomposition temperature of the reaction gas. In actual applications, the above preset temperature will be as high as more than 2000 degrees Celsius. The reaction gas introduced into the reaction chamber (initial molecules I11 and II12 as shown in Figure 1) undergoes a catalytic decomposition reaction on the hot wire with a preset temperature into active particles (active particles I110 and II as shown in Figure 1) Active particles II 120), the active particles are deposited and polymerized on the surface of the substrate 13 to form the thin film 14.

In the field of solar cells, HWCVD can be specifically used in thin film solar cells, passivation layer and anti-reflection layer deposition in crystalline silicon solar cells, and amorphous silicon/crystalline silicon heterojunction solar cells. Compared with PECVD, HWCVD has the advantages of fast deposition rate, high gas utilization rate, silicon-based thin film with extremely low surface recombination rate (at this time, the solar cell electrical conversion efficiency is high), and no plasma damage.

Referring to Figures 2 to 5, applying the above principles, embodiments of the present invention provide a hot filament chemical vapor deposition equipment, including a gas supply device (not shown in the figure), a vacuum chamber (not shown in the figure), and a gas distribution plate 20. Insulating support 21, heating wire 22, terminal 23, power supply 24 and carrier board 25. The vacuum chamber has an air inlet and an exhaust port. The air supply device supplies reaction gas into the vacuum chamber through the air inlet, and the exhaust gas is discharged from the vacuum chamber through the exhaust port. The air distribution plate 20 is horizontally accommodated in the vacuum chamber and is fastened close to the top of the vacuum chamber. The gas distribution plate 20 has a gas distribution area 200 and an installation area 201. A gas distribution through hole is provided in the gas distribution area 200. The reaction gas after entering the vacuum chamber passes through the gas distribution through hole to the vacuum chamber. Spray the lower area of the cavity. The mounting area 201 is composed of multiple rows of mounting portions 2010 . Each row of mounting parts 2010 is provided with a plurality of insulating supporting members 21 at intervals, and the plurality of insulating supporting members 21 located in the same row jointly carry the heating wire 22 extending in the horizontal direction. The heating wire 22 has an opposite first end and a second end, and both the first end and the second end are electrically connected to the horizontally arranged terminal posts 23 . One end of each terminal 23 connected to the heating wire 22 can provide elastic tension to the heating wire 22 so that the heating wire 22 is tightened when the heating wire 22 is heated and deformed. At this time, the heating wire 22 is always in a horizontal state. Multiple rows of heating wires 22 are connected in series to the power supply 24 through wires 27 . The carrier plate 25 is placed horizontally in the vacuum chamber and below the hot wire 22 for carrying the silicon wafer 26 .

The above-mentioned gas supply device may include a gas source cabinet, a gas supply pipeline, a valve, a flow meter, etc., wherein the gas source cabinet is used to store the reaction gas. The gas supply pipeline connects the gas source cabinet and the vacuum chamber, and is used to transport the reaction gas stored in the gas source cabinet into the vacuum chamber. In order to accurately control and detect the flow rate of the reaction gas delivered to the vacuum chamber, valves and flow meters can be sequentially installed on the gas supply pipeline in the direction from the gas source cabinet to the vacuum chamber. Among them, the flow rate of the reaction gas is controlled by controlling the opening of the valve, and the flow rate of the reaction gas transported into the vacuum chamber is monitored by a flow meter.

Referring to FIGS. 2 to 5 , the above reaction gas can be determined according to the type of pre-film formation on the silicon wafer 26 . For example, when a silicon dioxide film needs to be deposited on the silicon wafer 26 as a passivation layer, the reaction gas may be silane (SiH ₄ ) and oxygen (O ₂ ). For another example, when silicon nitride (Si ₃ N ₄ ) needs to be deposited on the silicon wafer 26 as a passivation layer, the reaction gas may be silicon dichloride (SiCl ₂ H ₂ ) and ammonia (NH ₃ ) . For another example, when polysilicon needs to be deposited on the silicon wafer 26 to form a conductive electrode, the reactive gas may be silane (SiH ₄ ).

Referring to FIGS. 2 to 5 , the above-mentioned vacuum chamber may be a closed rectangular cavity to fit the rectangular silicon wafer 26 . In order to facilitate the removal/placement of the silicon wafer 26, a door can be provided on one side or the top of the rectangular cavity, which is opened during removal and placement and closed during film formation. After the silicon wafer 26 is placed on the carrier plate 25 housed in the rectangular cavity, the rectangular cavity can be evacuated to form a vacuum chamber. At this time, it can be ensured that there are no impurities in the vacuum chamber, so as to optimize the cleanliness of the film-forming space of the silicon wafer 26 and thus improve the film-forming quality.

Referring to Figures 2 to 5, the above-mentioned air inlet and exhaust port can be opened on the non-opening surface of the rectangular cavity, wherein the air inlet is provided on one side of the chamber wall of the vacuum chamber above the air distribution plate 20, The exhaust port can be opened on the other side wall of the vacuum chamber below the air distribution plate 20, and the two chamber walls can be opposite chamber walls. Based on this, a circulation channel for the reaction gas can be formed from above the gas distribution plate 20 , through the gas distribution plate 20 , the hot wire 22 , and the silicon wafer 26 , as well as an exhaust gas exhaust channel from the silicon wafer 26 to the exhaust port. Put channel. The above-mentioned tail gas may be a mixed gas, and may specifically include residual reaction gases that have not participated in the film-forming reaction and gases generated after the film-forming reaction.

Referring to FIGS. 2 to 5 , the air distribution plate 20 has various shapes and is not specifically limited here. For example, when multiple silicon wafers 26 to be filmed are placed in a matrix on the carrier plate 25, at this time, in order to improve the uniformity or consistency of the reaction gas sprayed to all the silicon wafers 26 through the gas distribution plate 20, you can The gas distribution plate 20 is designed as a rectangular structure that completely covers a plurality of silicon wafers 26 distributed in a matrix.

Referring to Figures 2 to 5, the air distribution plate 20 can be fastened and arranged in various ways, which are not specifically limited here. For example, when the air distribution plate 20 is a rectangular air distribution plate 20, a rigid connecting rod can be detachably connected to the four corners of the air distribution plate 20, and then the rigid connecting rod can be firmly connected to the vacuum chamber. on the top cavity wall. That is, the air distribution plate 20 is hung horizontally in the vacuum chamber through rigid connectors. It should be understood that after the gas distribution plate 20 is hoisted, there will be a certain space between the upper surface of the gas distribution plate 20 and the top of the vacuum chamber to form a transport channel for the reaction gas from the air inlet to the gas distribution plate 20 .

In order to facilitate understanding of the air distribution area 200 and the installation area 201 in this embodiment, a specific example is used to explain below. It should be understood that the following example is only for explanation and not for limitation.

Referring to FIGS. 2 to 5 , for example, the silicon wafer 26 is a 6×6 matrix, that is, it includes 6 rows and 6 columns of silicon wafers 26 , and there are equal gaps between rows and between columns. At this time, the installation area 201 can be designed at the position of the corresponding air distribution plate 20 directly above each row of silicon wafers 26. At this time, the installation area 201 can include six rows of installation parts 2010. Areas other than the installation area 201 are designed as air distribution areas 200. With this arrangement, the gas distribution area 200 can be maximized to increase the coverage of the silicon wafer 26 by the reaction gas sprayed onto the silicon wafer 26 through the gas distribution area 200 . Based on this, the thickness uniformity of the film formed on the silicon wafer 26 is improved.

Referring to FIGS. 2 to 5 , six rows of mounting parts 2010 correspond to six rows of insulating supports 21 , and correspondingly, six rows of hot wires 22 . That is, a heating wire 22 is provided above each row of silicon wafers 26 . Moreover, the six heating wires 22 are coplanar (can be defined as a common surface), and the common surface is a horizontal common surface. There is a certain distance L between the common surface and the silicon chip 26, 5cm≤L≤10cm. For example, L=5cm, L=6cm, L=7cm, L=8cm, L=9cm or L=10cm.

Referring to Figures 2 to 5, each of the above-mentioned hot wires 22 has an equal diameter R ₁ , 0.25mm≤R ₁ ≤2mm, for example, R ₁ =0.25mm, R ₁ =0.5mm, R ₁ =0.75mm, R ₁ =1mm, R ₁ =1.5mm or R ₁ =2mm.

Referring to Figures 2 to 5, each of the above-mentioned heating wires 22 is made of the same material, which can be any one of tantalum, tungsten, rhenium or graphite.

Referring to FIGS. 2 to 5 , the above six heating wires 22 can be connected through wires 27 . For example, the terminal 23 located in the lower left corner can be connected to the positive terminal of the power supply 24, and the terminal 23 located in the upper right corner can be connected to the negative terminal of the power supply 24. At this time, with the terminal 23 located in the lower right corner as the starting point and the terminal 23 located in the upper left corner as the end point, guides are used to connect the remaining terminals 23 together in series.

Referring to Figures 2 to 5, in practical applications, after the chemical vapor deposition equipment for the hot wire 22 provided by the embodiment of the present invention is assembled, the hot wire 22 is tightly connected to the gas distribution plate 20 through the insulating support 21, that is, the hot wire 22 is The wire 22 and the air distribution plate 20 form an integrated structure. Based on this, the structure of the chemical vapor deposition equipment of the hot wire 22 can be effectively simplified.

Referring to Figures 2 to 5, in practical applications of the hot wire 22 chemical vapor deposition equipment provided by the embodiment of the present invention, the silicon wafer 26 to be formed can be placed horizontally on the carrier 25. At this time, the silicon wafer 26 placed horizontally can The piece 26 does not require any fastening devices. Based on this, compared with the vertical hot wire 22 chemical vapor deposition equipment provided by the existing technology, without the need to use magnetic buckles or covers to vertically fix the silicon wafer 26, problems caused by occlusion can be completely solved. The problem of inability to form film in blocked areas. At this time, the consistency or uniformity of the film thickness of the silicon wafer 26 can be improved.

Referring to Figures 2 to 5, after the silicon wafer 26 is placed horizontally on the carrier plate 25, the gas supply device can be controlled to supply the reaction gas into the vacuum chamber through the air inlet according to a preset flow rate (as mentioned above, the reaction gas can be a single gas, It can also be a mixed gas). At the same time, the exhaust port needs to be controlled to be always open during the film formation process so that the exhaust gas can be discharged out of the vacuum chamber in real time.

Referring to Figures 2 to 5, after the reaction gas is introduced for a certain period of time, the power supply 24 is started to heat the hot wire 22 to a preset temperature. That is, a film-forming method of "ventilating first and then heating" can be used. In this way, the input but not thermally decomposed reaction gas can be used to purge the vacuum chamber to optimize the cleanliness of the subsequent silicon wafer 26 film-forming environment, thereby improving the silicon wafer 26 film-forming environment. Tablet 26 film-forming purity.

Referring to FIGS. 2 to 5 , after the hot wire 22 is heated to a preset temperature, the hot wire 22 can be maintained at the preset temperature to efficiently decompose the reaction gas and thereby form a film on the silicon wafer 26 . During the process of heating up the heating wire 22 and maintaining it at the preset temperature, the heating wire 22 will tend to sag due to high temperature deformation. At this time, the plurality of insulating supports 21 provided corresponding to each hot wire 22 can provide upward support force for the hot wire 22. Based on this, the support force can offset the sagging force of the hot wire 22, thereby effectively reducing the heat. The risk of silk 22 changing from a sagging tendency to a sagging state. Moreover, corresponding to each hot wire 22 has The terminals 23 provided at the first end and the second end respectively can adaptively provide elastic pulling force when the hot wire 22 tends to sag. Based on this, it can be ensured that the heating wire 22 is always in a horizontal state. The distance between the always horizontal hot wire 22 and the silicon wafer 26 placed on the carrier plate 25 remains constant. Based on this, it can be ensured that the silicon-based film finally formed on the silicon wafer 26 has a consistent thickness, thereby improving the final result. The quality of the thin film solar cells formed.

Referring to Figures 2 to 5, because the hot wire 22 vapor deposition equipment provided by the present invention is different from the plasma enhanced chemical vapor deposition method, because the above equipment forms a film on the surface of the silicon wafer 26 through the high temperature catalytic decomposition reaction gas of the hot wire 22, Therefore, the decomposition efficiency of most reaction gases is much higher than that of PECVD. Based on this, the problems of large consumption of reaction gases and low decomposition efficiency can be effectively solved.

Referring to FIG. 3 , as a possible implementation, each row of mounting parts 2010 includes a plurality of first mounting holes 20100 that are spaced apart. The first mounting hole 20100 may be any one of a through hole or a blind hole, which is not specifically limited here. The shape of the first mounting hole 20100 may match the shape of the place where the insulating support 21 is assembled with the first mounting hole 20100. For example, when the top of the insulating support 21 is rectangular, the first mounting hole 20100 is a rectangular mounting hole. With this arrangement, the insulating support 21 can be inserted and fixed in the first installation hole 20100 to achieve horizontal lifting of the hot wire 22 . It has the advantages of simple structure and convenient installation.

As a possible implementation manner, each row of mounting portions 2010 is a mounting groove extending from the beginning of the row to the end of the row. The installation groove may be a blind groove that does not penetrate the air distribution plate 20 along the thickness direction of the air distribution plate 20 . Based on this, the position of the insulating supporting member 21 can be adjusted in the installation groove according to actual needs to adapt to the different requirements for the position of the insulating supporting member 21 of silicon wafers 26 of different specifications. That is, the spacing between adjacent insulating supporting members 21 can be adjusted according to the distance between the gaps between adjacent silicon wafers 26 . In other words, the applicable scope of the hot filament chemical vapor deposition equipment provided by the present invention can be expanded.

Referring to FIGS. 2 to 5 , as a possible implementation manner, when a plurality of silicon wafers 26 distributed in an array are placed horizontally on the carrier board 25 , each row of silicon wafers 26 corresponds to a row of mounting portions 2010 above. At this time, there are gaps between any two adjacent silicon wafers 26 in the same row, and an insulating support 21 is provided above each gap.

Referring to FIGS. 2 to 5 , as an example, when the silicon wafers 26 are in a 6×6 matrix, five first mounting holes 20100 are opened on the air distribution plate 20 corresponding to each row of silicon wafers 26 . The first mounting hole 20100 is opened above the gap between two adjacent silicon wafers 26 . Correspondingly, install the first installation above The insulating supporting member 21 in the hole 20100 is also located above the gap between two adjacent silicon wafers 26 .

Referring to Figures 2 to 5, the insulating support 21 is located above the gap between any two adjacent silicon wafers 26. At this time, the insulating support 21 will not block the film formation area of the silicon wafer 26. Based on this, it is possible to effectively avoid the problem that the film formation area of the silicon wafer 26 is blocked and the film formation cannot be formed or the film formation is uneven.

Referring to FIGS. 6 to 9 , as a possible implementation, the insulating support member 21 is a holding rod, and the holding rod includes a connecting section 210 and a load-bearing section 211 connected with the connecting section 210 . In the assembled state, the connecting section 210 is tightly connected to the mounting part 2010, and the bearing section 211 is suspended. A bearing hole 212 is formed through the bearing section 211 along the length direction of the heating wire 22 . The diameters of the bearing holes 212 located on the bearing sections 211 in the same row are equal and the central axes are collinear. The diameters of the bearing holes 212 located in different rows are equal and the central axes are coplanar.

Referring to FIGS. 6 to 9 , with this arrangement, when the multiple hot wires 22 are assembled, the multiple hot wires 22 are coplanar, and there is a gap between each hot wire 22 and the silicon chip 26 placed on the carrier plate 25 . The vertical distance is equal. Based on this, within one film formation cycle, and when the concentration of reactive gases sprayed by the gas distribution plate 20 onto the surfaces of different silicon wafers 26 and the gas supply speed are basically the same, the film thicknesses on different silicon wafers 26 can be basically the same. be consistent. Based on this, while improving the film-forming quality of the silicon wafer 26, the quality of the thin-film solar cell is further optimized.

Referring to Figures 6 to 9, as an example, the connecting section 210 is coaxially connected to the load-bearing section 211. The connection section 210 and the load-bearing section 211 can be an integrated structure or a split structure, and then use any existing method. Detachably connected coaxially. Specifically, the connecting section 210 can be a rectangular parallelepiped structure, the load-bearing section 211 can be a rectangular parallelepiped structure with a smaller cross-sectional area than the connecting section 210, and the suspended end of the load-bearing section 211 can be rounded. Based on this, the first mounting hole 20100 assembled with the connecting section 210 may be a rectangular groove. At this time, the size of the rectangular groove can be determined by the size of the connecting section 210. For example, the length of the rectangular groove is 6mm~120mm, the width is 3mm~60mm, and the depth is 0.1mm~2mm. Correspondingly, the length and width of the connecting end are The specific dimensions of height and height can be slightly smaller than the length, width and depth of the rectangular groove. For another example, the spacing between the first mounting holes 20100 in the same row is determined according to the size of the silicon chip 26 below. Specifically, the spacing between the first mounting holes 20100 may be 160 mm to 400 mm.

Referring to Figures 6 to 9, during actual assembly, a threaded hole 213 can be opened in the connecting section 210. Correspondingly, a threaded hole 213 can be opened in the first mounting hole 20100, and then the threaded hole 213 can be screwed on at the same time. The screws in the threaded holes 213 detachably connect the insulating supporting member 21 to the air distribution plate 20 .

Referring to FIGS. 6 to 9 , as an example, the bearing hole 212 is a circular hole with a diameter R ₂ , and the diameters R ₁ and R ₂ of the heating wire 22 penetrating the bearing hole 212 may have the following relationship, 2R ₁ ≤ R ₂ ≤5R ₁ , when the specific value of the diameter R ₁ of the hot wire 22 is as mentioned above, 0.5mm ≤ R ₂ ≤ 10mm, for example, R ₂ =0.5mm, R ₂ =1mm, R ₂ =1.5mm, R ₂ =2mm, _R2 =3mm, _R2 =4mm... _R2 =10mm. With this arrangement, since the diameter of the hot wire 22 is smaller than the diameter of the bearing hole 212, the hot wire 22 is relatively easy to insert into the assembly hole during the assembly process. Based on this, the assembly efficiency can be improved. After the assembly is completed, that is, when the heating wire 22 passes through the bearing hole 212 and is supported by the hole wall of the bearing hole 212 , the contact area between the heating wire 22 and the bearing hole 212 is relatively small. In other words, the area where the hole wall of the bearing hole 212 covers the heating wire 22 is relatively small. At this time, the wire segment of the heating wire 22 that is in contact with the bearing hole 212 has a larger heat conduction channel. Based on this, each wire segment of the same heating wire 22 (wholly can be divided into a contact segment in contact with the load-bearing hole 212 and a first end and a second end located between two adjacent load-bearing holes 212 and opposite to the hot wire 22 The temperature radiated from the suspended section) to the silicon wafer 26 is basically the same, so that each area of the same silicon wafer 26 can form a silicon-based film with a consistent thickness. Moreover, the contact area between the insulating support 21 and the heating wire 22 can also be reduced, and the degree of softening and deformation of the heating wire 22 under the action of high temperature and gravity can be reduced when the heating wire 22 is installed horizontally.

Referring to FIGS. 6 to 9 , as a possible implementation manner, the central axis of each heating wire 22 is collinear with the central axis of the terminals 23 provided at both ends of the heating wire 22 . With this arrangement, when the hot wire 22 sag due to high-temperature deformation, the relative elastic pulling force provided by the terminals 23 respectively arranged at the first end and the second end of the hot wire 22 to both ends of the hot wire 22 is basically in line with the center of the hot wire 22 The axes are collinear. In other words, the elastic pulling force has no components in other directions in the extension direction of the length of the hot wire 22 , that is, the elastic pulling force provided by the terminal 23 to both ends of the hot wire 22 can basically be used to extend the length of the hot wire 22 . At this time, when the drooping hot wire 22 is quickly straightened, the hot wire 22 can always be in a horizontal state during use.

As a possible implementation manner, the hot wire chemical vapor deposition equipment further includes two carriers (not shown in the figure), and the two carriers are spaced apart on both sides of the gas distribution plate 20 along the extension direction of the hot wire 22 . Second mounting holes (not shown in the figure) are formed on each carrier frame at intervals in a direction perpendicular to the extending direction of the heating wire 22 . The terminal posts 23 are assembled in the second mounting holes in a transition or interference fit manner. At this time, each terminal post 23 is collinear with the central axis of the second installation hole with which it is assembled.

As an example, both bearing frames can be hollow structures to facilitate the discharge of exhaust gas. The terminal post 23 is carried by the second assembly hole on the carrying frame. The carrier can be set not far from the carrier board 25. At this time, after the terminals 23 are assembled on the carrier, each row of hot wires 22 only needs to extend a short distance from the film-formed edge of the silicon wafer 26. Then the electrical connection between the hot wire 22 and the terminal 23 can be realized. The wires 27 used to connect adjacent rows of terminal posts 23 can be fixed on the outside of the carrier frame to standardize the routing of the wires 27 .

As a second example, when two carrier frames are provided, the air distribution panel 20 may be supported by the tops of the two carrier frames. That is to say, the air distribution panel 20 changes from the "hoisting" mentioned above to the carrier support in this embodiment. Based on this, the stability of the installation of the gas distribution plate 20 can be improved, so that the path of the reaction gas sprayed through the gas distribution plate 20 to the surface of the silicon wafer 26 is consistent, and ultimately the consistency of the film thickness of the silicon wafer 26 is improved.

Referring to FIGS. 10 to 13 , as a possible implementation, each terminal 23 includes a fixing bolt 230 , a first terminal 231 , an elastic member 233 and a second terminal 232 . The fixing bolt 230 has an opposite first terminal 232 . The first receiving groove 2300 is opened from the end surface of the first end in the direction close to the second end, and the second receiving groove 2301 is opened from the end surface of the second end in the direction close to the first end. The first connection terminal 231 is detachably fastened in the first receiving groove 2300 , and the first connection terminal 231 is used to connect the wire 27 or the power supply 24 . The elastic member 233 is accommodated in the second receiving groove 2301, and one end of the elastic member 233 is tightly connected to the bottom of the second receiving groove 2301, and the other end is suspended. At least part of the second connection terminal 232 is received in the second receiving groove 2301 , and one end of the second connection terminal 232 is tightly connected to the suspended end of the elastic member 233 , and the other end is connected to the hot wire 22 . The elastic member 233 provides an elastic pulling force for the second terminal 232. When the hot wire 22 pulls the second terminal 232 outward, the elastic member 233 exerts an elastic pulling force on the second terminal 232 to close the bottom of the second receiving groove 2301. Pull the hot wire 22 in the direction.

Referring to FIGS. 10 to 13 , the above-mentioned fixing bolt 230 may further include a conductive fixing pin 230 body and an insulating layer disposed (specifically provided by coating) on the outer surface of the conductive fixing pin 230 body. At this time, the first receiving groove 2300 and the second receiving groove 2301 are both opened on the body of the conductive fixing bolt 230 oppositely. Both the first receiving groove 2300 and the second receiving groove 2301 may be blind grooves and share the bottom of the grooves. The above-mentioned fixing bolt 230 may be a cylindrical structure, and the outer diameter of the cylindrical shape may be substantially equal to the diameter of the second mounting hole on the carrier frame.

Referring to Figures 10 to 13, as an example, the first connection terminal 231 is assembled to the first receiving After the groove 2300, the outer end surface of the first terminal 231 is flush with the outer end surface of the first receiving groove 2300.

Referring to FIGS. 10 to 13 , as a second example, in the initial state, a part of the second terminal 232 is accommodated in the second receiving groove 2301 . In practical applications, under the action of the elastic tension provided by the elastic member 233, the second terminal 232 can slide in a direction close to the bottom of the groove. After sliding to the extreme position, the outer end surface of the second terminal 232 can be in contact with the second terminal 232. The outer end surface of the receiving groove 2301 is flush, or the outer end surface of the second terminal 232 protrudes from the outer end surface of the second receiving groove 2301 .

Referring to FIGS. 10 to 13 , as a third example, in the initial state, all of the second connection terminals 232 are accommodated in the second accommodation groove 2301 . In practical applications, under the action of the elastic tension provided by the elastic member 233, the second terminal 232 can slide in a direction close to the bottom of the groove. After sliding to the extreme position, the outer end surface of the second terminal 232 is recessed into the second The inside of the receiving tank 2301.

Referring to FIGS. 10 to 13 , the elastic member 233 may be a tension spring, that is, when a tension force is applied to the tension spring, the tension spring will contract to apply a reverse tension force to the hot wire 22 .

Referring to Figures 10 to 13, when the above technical solution is adopted, the terminal 23 is composed of a fixing bolt 230, a first terminal 231, an elastic member 233 and a second terminal 232, which has a simple and compact structure. In practical applications, when the hot wire 22 deforms at high temperature and has a tendency to sag, the hot wire 22 with a tendency to sag will exert an outward pulling force on the elastic member 233. Since the elastic member 233 has the property of rebounding, therefore, when When the resilience of the elastic member 233 is greater than the pulling force exerted by the hot wire 22 on the elastic member 233 , the hot wire 22 with a tendency to sag is pulled to a horizontal state by the elastic member 233 again. Moreover, under the action of the rebound force (ie, the elastic tension defined above), the second terminal 232 moves in the direction closer to the bottom of the groove in the second receiving groove 2301, that is, the second terminal 232 is initially assembled in the second receiving groove 2301. The moving direction of the terminal 232 is limited to coincide with the extending direction of the heating wire 22 . Based on this, when the hot wire 22 is deformed at high temperature and has a tendency to sag (at this time, it does not really sag), the hot wire 22 can be flattened in time under the action of the elastic member 233's resilience. At this time, it can be ensured that the heating wire 22 is always in a horizontal state during use, instead of being in a drooping state for a short moment and then being pulled to a horizontal state.

Referring to Figures 10 to 13, as a possible implementation, a wiring groove is opened from one end of the second terminal 232 away from the elastic member 233 to the side opposite to it. In the assembled state, the hot wire 22 is inserted into the wiring groove. . Each terminal 23 also includes a locking member 234, which is inserted radially from the fixing bolt 230 and pressed onto the heating wire 22 located in the wiring slot. The above-mentioned locking member 234 can So tighten the screw. During the assembly process, the hot wire 22 can be inserted into the wiring slot, and then the locking member 234 is used to lock the hot wire 22 in the wiring slot, which has the advantages of simple assembly and high assembly efficiency. When the hot wire 22 needs to be disassembled from the second terminal 232, the locking member 234 can be removed first, and then the hot wire 22 can be pulled out from the wiring slot, which has the advantage of easy disassembly.

Referring to Figures 10 to 13, as a possible implementation, at least one set of releasable spring buckles 235 is provided on the groove wall of the first receiving groove 2300 and along the depth direction of the groove, and the first terminal 231 is inserted into the first receiving groove. After 2300, at least one set of releasable spring buckles 235 are used to fix the first terminal 231. For example, three or four groups of releasable spring buckles 235 may be arranged at equal intervals. With this arrangement, after the assembly is completed, at least one set of releasable spring buckles 235 can provide a clamping force for the first terminal 231 so that the axial movement and rotation of the first terminal 231 in the first receiving groove 2300 are restricted. . Based on this, the assembly stability of the first connection terminal 231 in the first receiving groove 2300 can be improved.

In a second aspect, the present invention also provides a silicon-based thin film deposition method. The silicon-based thin film deposition method applies the hot filament chemical vapor deposition equipment provided by the first aspect and/or any implementation of the first aspect. It should be explained that, The above-mentioned silicon-based film can be any one of crystalline silicon, polycrystalline silicon, microcrystalline silicon, amorphous silicon, silicon oxide, silicon nitride, silicon carbide, silicon oxynitride, silicon nitride carbide or silicon oxycarbide. The silicon-based film is deposited The method includes the following steps:

S10. Provide at least one silicon wafer, and place the silicon wafer horizontally on the carrier board.

S11. At the first time t ₁ , the gas supply device is controlled to supply the reaction gas into the vacuum chamber through the air inlet, and the reaction gas is sprayed to the upper surface of the silicon wafer through the gas distribution plate; where the reaction gas is determined based on the silicon-based film; At the same time, the exhaust port is controlled to be open;

S12. At the second time t ₂ , control the power supply to the hot wire to heat the hot wire to the preset temperature, t ₂ -t ₁ >0s; at this time, the reaction gas is separated into atoms on the surface of the hot wire, and the atoms are The silicon dangling bonds on the surface of the silicon wafer are bonded to form a silicon-based film on the surface of the silicon wafer; during the process of heating the hot wire to the preset temperature and maintaining the hot wire at the preset temperature, when the hot wire has a tendency to sag due to high deformation At this time, the supporting member and the terminal provide supporting force and elastic tension for the hot wire respectively, so that the hot wire is always in a horizontal state.

Compared with the existing technology, the beneficial effects of the silicon-based thin film deposition method provided by the present invention are the same as those of the first aspect and/or the hot filament chemical vapor deposition equipment provided by any implementation of the first aspect, and are not discussed here. To elaborate.

In a third aspect, the present invention also provides a solar cell. The solar cell sheet is processed and formed by using the hot wire chemical vapor deposition equipment provided by the first aspect and/or any implementation of the first aspect. Or, the solar cells are formed using the silicon-based thin film deposition method provided in the second aspect.

Compared with the existing technology, the beneficial effects of the silicon-based thin film deposition method provided by the present invention are the same as those of the first aspect and/or the hot filament chemical vapor deposition equipment provided by any implementation of the first aspect, and are not discussed here. To elaborate.

In the above description of the embodiments, specific features, structures, materials or characteristics may be combined in any suitable manner in any one or more embodiments or examples.

The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any person familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed by the present invention. should be covered by the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims.

Claims (10)

1. A hot wire chemical vapor deposition equipment, characterized by including:

   A gas supply device, the gas supply device is used to supply reaction gas;

   A vacuum chamber, the vacuum chamber has an air inlet and an exhaust port, the reaction gas enters the vacuum chamber through the air inlet, and the exhaust gas is discharged from the vacuum chamber through the exhaust port;

   An air distribution plate is horizontally housed in the vacuum chamber and is fastened close to the top of the vacuum chamber; the air distribution plate has an air distribution area and an installation area; on the A gas distribution through hole is provided in the gas distribution area, and the reaction gas after entering the vacuum chamber is sprayed to the lower area of the vacuum chamber through the gas distribution through hole; the installation area is composed of multiple rows of installation parts;

   Each row of the mounting parts is provided with a plurality of insulating supports at intervals; the plurality of insulating supports located in the same row jointly carry a heating wire extending in the horizontal direction; the heating wire has an opposite first end and a second end, the first end and the second end are both electrically connected to horizontally arranged terminals; one end of each terminal connected to the hot wire can provide elastic pulling force to the hot wire to Tighten the hot wire when the hot wire is heated and deformed. At this time, the hot wire is always in a horizontal state;

   A power supply, multiple rows of the hot wires are connected in series with the power supply;

   A carrier plate is placed horizontally in the vacuum chamber and below the hot wire, and is used to carry silicon wafers.
2. The hot wire chemical vapor deposition equipment according to claim 1, characterized in that each row of the mounting parts includes a plurality of first mounting holes opened at intervals; or, each row of the mounting parts is a self-arranged head. A mounting groove extending through the end of the row.
3. The hot filament chemical vapor deposition equipment according to claim 1, characterized in that when a plurality of silicon wafers distributed in an array are placed horizontally on the carrier plate, the top of each row of silicon wafers corresponds to a row of the silicon wafers. At this time, there is a gap between any two adjacent silicon wafers in the same row, and an insulating supporting member is provided above each gap.
4. The hot wire chemical vapor deposition equipment according to claim 1, characterized in that the insulating support member is a holding rod, and the holding rod includes a connecting section and a load-bearing section connected with the connecting section;

   In the assembled state, the connecting section is tightly connected to the installation part, and the load-bearing section is suspended; a load-bearing hole is opened through the load-bearing section along the length extension direction of the hot wire; it is located on the load-bearing sections in the same row. The load-bearing holes have the same apertures and their central axes are collinear, and the load-bearing holes located in different rows have the same apertures and their central axes are coplanar.
5. The hot wire chemical vapor deposition equipment according to claim 4, characterized in that the hot wire has a diameter R ₁ , the bearing hole has a diameter R ₂ , and 2R ₁ ≤ R ₂ ≤ 5R ₁ .
6. The hot wire chemical vapor deposition equipment according to claim 1, characterized in that, in the assembled state, the central axis of each hot wire is the same as the central axis of the terminals provided at both ends of the hot wire. line; and/or,

   The hot wire chemical vapor deposition equipment also includes two carriers, which are spaced apart on both sides of the gas distribution plate along the extension direction of the hot wire; the upper edge of each carrier is in contact with the hot wire. Second mounting holes are spaced in directions perpendicular to the extension direction; the terminal posts are assembled in the second installation holes in a transitional or interference fit manner. At this time, each terminal post is assembled with its The central axes of the second mounting holes are collinear.
7. The hot wire chemical vapor deposition equipment according to claim 1, characterized in that each of the terminals includes:

   Fixed bolt, the fixed bolt has an opposite first end and a second end, a first receiving groove is opened from the end surface of the first end in a direction close to the second end, and a first receiving groove is opened from the end surface of the second end close to the second end. A second receiving groove is provided in the direction of the first end;

   A first connection terminal, the first connection terminal is detachably fastened in the first receiving groove, and the first connection terminal is used to connect the wire or power supply;

   Elastic member, the elastic member is accommodated in the second receiving groove, and one end of the elastic member is tightly connected to the bottom of the second receiving groove, and the other end is suspended;

   A second connection terminal, at least a part of the second connection terminal is accommodated in the second receiving groove, and one end of the second connection terminal is tightly connected to the suspended end of the elastic member, and the other end is connected to the second connection terminal. The hot wire connection; the elastic member provides elastic pulling force for the second wiring terminal. When the hot wire pulls the second wiring terminal outward, the elastic member applies elastic pulling force to the second wiring terminal. The heating wire is pulled in a direction close to the bottom of the second receiving groove.
8. The hot wire chemical vapor deposition equipment according to claim 7, wherein the fixing bolt includes a conductive fixing bolt body and an insulating layer disposed on the outer surface of the conductive fixing bolt body; the first containing groove and the third Two receiving grooves are provided on the conductive fixing bolt body; and/or,

   A wiring slot is opened from one end of the second terminal away from the elastic member to the side opposite to it. In the assembled state, the hot wire is inserted into the wiring slot; each terminal also includes a lock. The locking piece is inserted from the radial direction of the fixing bolt and pressed onto the hot wire located in the wiring groove; and/or,

   At least one set of releasable springs is provided on the groove wall of the first receiving groove and along the depth direction of the groove. After the first terminal is inserted into the first receiving groove, the at least one set of releasable spring buckles is used to fix the first terminal.
9. A silicon-based thin film deposition method, characterized in that the silicon-based thin film deposition method applies the hot wire chemical vapor deposition equipment according to any one of claims 1 to 8, and the silicon-based thin film deposition method includes the following steps:

   Provide at least one silicon wafer, and place the silicon wafer horizontally on the carrier;

   At the first time t ₁ , the gas supply device is controlled to supply the reaction gas into the vacuum chamber through the air inlet, and the reaction gas is sprayed to the upper surface of the silicon wafer through the gas distribution plate; Wherein, the reaction gas is determined based on the silicon-based film; at the same time, the exhaust port is controlled to be open;

   At the second time t ₂ , the power supply is controlled to supply power to the hot wire to heat the hot wire to a preset temperature, t ₂ -t ₁ >0s; at this time, the reaction gas flows in the hot wire The surface is separated into atoms, and the atoms are bonded to silicon dangling bonds on the surface of the silicon wafer to form a silicon-based film on the surface of the silicon wafer; after the hot wire is heated to the preset temperature and the hot wire is maintained During the preset temperature process, when the hot wire tends to sag or sag when heated, the supporting member provides supporting force for the hot wire, and the terminal provides pulling force for the hot wire. So that the hot wire is always in a horizontal state.
10. A solar cell, characterized in that the solar cell is formed using the hot filament chemical vapor deposition equipment described in any one of claims 1 to 8, or the solar cell is formed using the silicon-based film described in claim 9 Processed by deposition method.