Method for preparing thin film and semiconductor process device

Abstract

The present disclosure provides a method for preparing a thin film and a semiconductor process device. The method comprises: after respectively placing a plurality of substrates into at least two carrying components in a process chamber, controlling the process chamber to cyclically alternate between a gas introduction process and a gas soaking process, and at least during the gas soaking process in the process chamber, controlling the at least two carrying components to perform asynchronous glow discharge, wherein the gas introduction process is used for introducing a process gas required for depositing a thin film into the process chamber, and the flow rate of the gas in the process chamber during the gas soaking process is less than the flow rate of the gas in the process chamber during the gas introduction process. Thus, the uniformity, stability and quality of a prepared thin film such as a tunnel oxide layer can be improved.

Description

A thin film preparation method and semiconductor process equipment TECHNICAL FIELD

[0001] The present application relates to the technical field of semiconductor technology, in particular to a thin film preparation method and semiconductor process equipment. BACKGROUND

[0002] The key technology of a TOPCon (Tunnel Oxide Passivated Contact) solar cell is to prepare an ultra-thin tunnel oxide layer and a highly doped polysilicon thin layer. At present, a tubular PECVD (Plasma Enhanced Chemical Vapor Deposition) device is used to prepare the tunnel oxide layer. However, the quality of the tunnel oxide layer prepared by the current tubular PECVD device is poor, which leads to a low conversion efficiency of the solar cell. SUMMARY

[0003] The present application discloses a thin film preparation method and semiconductor process equipment to improve the quality of the tunnel oxide layer prepared by the tubular PECVD device.

[0004] In a first aspect, the present application discloses a thin film deposition method applied to a semiconductor process equipment, wherein the semiconductor process equipment comprises a process chamber, and at least two bearing components are arranged in the process chamber and used to bear substrates. The method comprises the following steps: after the plurality of substrates are respectively placed in the at least two bearing components, the circulation of the alternately performed ventilation process and the gas retention process in the process chamber is controlled, and the asynchronous glow discharge of the at least two bearing components is controlled at least when the gas retention process is performed in the process chamber. The ventilation process is used to ventilate the process gas required for depositing the thin film into the process chamber. The flow speed of the gas in the process chamber when the gas retention process is performed is less than the flow speed of the gas in the process chamber when the ventilation process is performed.

[0005] In some embodiments, the semiconductor process equipment further comprises a gas inlet assembly and a gas exhaust assembly. The gas inlet assembly is used to ventilate the process gas into the process chamber, and the gas exhaust assembly is used to exhaust the process chamber to control the air pressure in the process chamber. The control of the alternately performed ventilation process and the gas retention process in the process chamber comprises the following steps: the gas exhaust assembly is controlled to exhaust the process chamber, and the gas inlet assembly is controlled to ventilate the process gas into the process chamber. After the air pressure in the process chamber reaches a first preset air pressure, the gas inlet assembly is controlled to stop ventilating the process gas into the process chamber, and the gas exhaust assembly is controlled to stop exhausting the process chamber.

[0006] In some embodiments, the first preset air pressure is greater than or equal to 100 Pa and less than or equal to 10,000 Pa.

[0007] In some embodiments, the semiconductor processing equipment further comprises a power supply assembly configured to provide RF signals to the at least two supporting components respectively, the RF signals being configured to excite process gas in the process chamber to generate plasma by glow discharge, and the controlling the at least two supporting components to glow discharge asynchronously comprises: controlling the power supply assembly to provide RF signals to the at least two supporting components with non-overlapping RF on periods, the RF on period being a period in which the RF signals excite process gas in the process chamber to generate plasma by glow discharge.

[0008] In some embodiments, there is a time delay between the RF signals of any two of the at least two supporting components, the time delay being greater than or equal to a length of the RF on period and less than or equal to a difference between the length of the RF on period and a length of an RF off period, the RF off period being a period in a signal cycle other than the RF on period.

[0009] In some embodiments, a ratio of the length of the RF on period to the length of the RF off period of the RF signal of any of the supporting components is greater than or equal to 1 / 6 and less than or equal to 1 / 200.

[0010] In a second aspect, the present application discloses a semiconductor processing equipment, comprising a process chamber, a gas inlet assembly, a gas exhaust assembly, a power supply assembly and a control assembly; the process chamber is provided with at least two supporting components, the supporting components being configured to support a substrate; the gas inlet assembly is configured to introduce process gas into the process chamber; the gas exhaust assembly is configured to exhaust the process chamber to control air pressure in the process chamber; the power supply assembly is configured to provide RF signals to the at least two supporting components respectively; and the control assembly comprises at least one memory and at least one processor, the memory storing a computer program, and the processor is configured to execute the computer program to implement the thin film preparation method according to any one of the above aspects.

[0011] In some embodiments, the gas inlet assembly comprises a gas buffering component and a gas path control component; the gas buffering component is arranged between the gas supply component and the process chamber, and is used to buffer the process gas provided by the gas supply component and transmit the process gas to the process chamber when the gas path between the gas buffering component and the process chamber is opened; the speed of the process gas transmitted by the gas buffering component to the process chamber is greater than the speed of the process gas transmitted by the gas supply component to the gas buffering component; the gas path control component is arranged between the gas buffering component and the gas supply component, and is used to control the opening or closing of the gas path between the gas buffering component and the gas supply component.

[0012] In some embodiments, the gas inlet assembly further comprises a pressure measuring component; the pressure measuring component is arranged on the gas buffering component and is used to measure the gas pressure inside the gas buffering component.

[0013] In some embodiments, the gas inlet assembly further comprises a first one-way control component, a second one-way control component and a manual control component; the first one-way control component is arranged between the gas supply component and the gas path control component, the second one-way control component is arranged between the gas buffering component and the process chamber, and the manual control component is arranged between the first one-way control component and the gas path control component.

[0014] The thin film preparation method and the semiconductor process equipment disclosed in the present application can reduce the flowability of the gas in the process chamber while ensuring that the process chamber has the process gas required for depositing the thin film, thereby avoiding the problem of uneven distribution of plasma in the process chamber caused by the large flowability of the gas, and further improving the uniformity and quality of the prepared thin film such as the tunnel oxide layer.

[0015] And, because the asynchronous glow discharge of the at least two supporting components is controlled at least when the gas is filled in the process chamber, not only the problem of uneven distribution of plasma in the process chamber caused by the plasma generated by the glow discharge of one supporting component and the byproduct used by another supporting component for generating plasma by glow discharge can be avoided, but also the problem of affecting the stability of the thin film preparation such as the tunneling oxide layer caused by the discharge interference between the supporting components can be avoided, thereby further improving the uniformity and stability of the prepared thin film such as the tunneling oxide layer, and further improving the quality of the prepared thin film such as the tunneling oxide layer. BRIEF DESCRIPTION OF DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the background art, the drawings needed to be used in the embodiments of the present application or the background art will be described below.

[0017] FIG. 1 is a schematic structural diagram of a tubular PECVD device.

[0018] FIG. 2 is a schematic diagram of the RF signals provided by a power supply assembly to two supporting components.

[0019] FIG. 3 is a flowchart of a thin film preparation method disclosed by the embodiments of the present application.

[0020] FIG. 4 is a schematic diagram of the connection relationship between a power supply assembly and two supporting components disclosed by the embodiments of the present application.

[0021] FIG. 5 is a schematic diagram of the asynchronous RF signals provided by a power supply assembly to two supporting components disclosed by the embodiments of the present application.

[0022] FIG. 6 is a schematic structural diagram of a gas inlet assembly and a gas extraction assembly disclosed by the embodiments of the present application.

[0023] FIG. 7 is a schematic structural diagram of another gas inlet assembly disclosed by the embodiments of the present application. DETAILED DESCRIPTION

[0024] The technical solutions in the embodiments of the present application will be described clearly and completely below in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0025] As shown in FIG. 1, which is a schematic diagram of a structure of a tube PECVD device, the tube PECVD device includes a process chamber 1, a gas inlet assembly 2, a gas outlet assembly 3, and a power supply assembly 4. The process chamber 1 is provided with two supporting components 10 for supporting a wafer or other substrate, and the supporting components 10 include but are not limited to graphite boats. The process chamber 1 includes but is not limited to a furnace tube. The gas inlet assembly 2 is used to introduce process gas into the process chamber 1. The gas outlet assembly 3 is used to pump the process chamber 1 to control the air pressure in the process chamber 1. The power supply assembly 4 is used to provide RF signals to the two supporting components 10, respectively. The RF signals are used to excite the process gas in the process chamber 1 to generate plasma through glow discharge, so that the plasma is deposited on the surface of the wafer or other substrate to form a tunnel oxide layer or other thin film. However, the tunnel oxide layer prepared by the current tube PECVD device has poor quality, which leads to low conversion efficiency of a solar cell.

[0026] The inventors have found that, because one of the supporting components 10 is arranged close to the gas inlet of the process chamber 1 and the other supporting component 10 is arranged close to the gas outlet of the process chamber 1, during the process that the gas inlet assembly 2 continuously introduces process gas into the process chamber 1 through the gas inlet and the gas outlet assembly 3 continuously pumps the process chamber 1, the gas in the process chamber 1 flows from the gas inlet to the gas outlet, which leads to the plasma generated by the supporting component 10 close to the gas inlet flowing to the supporting component 10 close to the gas outlet, resulting in uneven distribution of the plasma in the process chamber 1, which further leads to poor uniformity of the tunnel oxide layer or other thin film prepared in the process chamber 1, and further leads to poor quality of the tunnel oxide layer or other thin film.

[0027] In addition, because the power supply assembly 4 simultaneously provides synchronous RF signals to the two supporting components 10 as shown in FIG. 2, the two supporting components 10 glow discharge at the same time, and the plasma and by-products generated by the supporting component 10 close to the gas inlet flow to the supporting component 10 close to the gas outlet, which leads to the plasma and by-products being continuously used for glow discharge to generate plasma by the supporting component 10 close to the gas outlet, further aggravating the uneven distribution of the plasma in the process chamber 1, further aggravating the uniformity of the tunnel oxide layer or other thin film, and the discharge interference between the supporting components 10 affects the stability of the preparation of the tunnel oxide layer or other thin film, leading to poor quality of the tunnel oxide layer or other thin film.

[0028] Based on this, the application discloses a thin film preparation scheme. By controlling the process chamber to alternately perform a ventilation process with a large gas flow speed and a gas retention process with a small gas flow speed, the gas flow in the process chamber is reduced while ensuring that the process chamber has the process gas required for depositing a thin film, the uniformity of the prepared tunnel oxide layer and other thin films is improved, the uniformity and stability of the prepared tunnel oxide layer and other thin films are further improved by controlling the asynchronous glow discharge of at least two supporting components at least when the gas retention process is performed in the process chamber, and the quality of the prepared tunnel oxide layer and other thin films is improved.

[0029] As an implementation form of the disclosure, the application discloses a thin film preparation method for preparing a tunnel oxide layer and other thin films. The thin film preparation method is applied to a tubular PECVD device and other semiconductor process devices. Referring to FIG. 1, the semiconductor process device includes a process chamber 1. At least two supporting components 10 are arranged in the process chamber 1 and used to support a wafer and other substrates. As shown in FIG. 3, which is a flowchart of the thin film preparation method disclosed by the application, the method includes the following steps.

[0030] S101: After the multiple substrates are respectively placed in the at least two supporting components 10, the ventilation process and the gas retention process are alternately performed in the process chamber 1. At least when the gas retention process is performed in the process chamber 1, the asynchronous glow discharge of the at least two supporting components 10 is controlled.

[0031] Because the ventilation process is used to introduce the process gas required for depositing a thin film into the process chamber 1, it can be ensured that the process chamber 1 has the process gas required for depositing a thin film. Because the flow speed of the gas in the process chamber 1 when the gas retention process is performed is smaller than the flow speed of the gas in the process chamber 1 when the ventilation process is performed, the gas flow in the process chamber 1 can be reduced, thereby avoiding the problem of uneven distribution of plasma in the process chamber 1 caused by the large gas flow, and further improving the uniformity of the prepared tunnel oxide layer and other thin films, and further improving the quality of the prepared tunnel oxide layer and other thin films.

[0032] Because at least when the gas retention process is performed in the process chamber 1, the asynchronous glow discharge of the at least two supporting components 10 is controlled, not only can the problem of uneven distribution of plasma in the process chamber 1 caused by the plasma and by-products generated by the glow discharge of one supporting component 10 being continuously used for generating plasma by the glow discharge of another supporting component 10 be avoided, but also the problem of the stability of the preparation of the tunnel oxide layer and other thin films being affected by the discharge interference between the supporting components 10 can be avoided, thereby further improving the uniformity and stability of the prepared tunnel oxide layer and other thin films, and further improving the quality of the prepared tunnel oxide layer and other thin films.

[0033] In addition, the circulation in the process chamber 1 alternately carries out the aeration process and the gas smothering process, which can improve the utilization rate of the process gas, reduce the gas loss, and reduce the production cost.

[0034] In some embodiments of the present application, the at least two supporting components 10 can be controlled to carry out asynchronous glow discharge only when the gas smothering process is carried out in the process chamber 1, and the at least two supporting components 10 can be controlled to not carry out glow discharge when the aeration process is carried out in the process chamber 1. In this way, not only can the plasma and by-products generated by the glow discharge of one supporting component 10 flow to another supporting component 10, but also the plasma and by-products generated by one supporting component 10 can be annihilated before another supporting component 10 carries out glow discharge, so that the plasma and by-products generated by one supporting component 10 cannot be continuously used for glow discharge to generate plasma by another supporting component 10. Therefore, the uniformity of the plasma in the process chamber 1 can be further improved, and the uniformity and quality of the tunnel oxide layer and other thin films prepared can be further improved.

[0035] Of course, the present application is not limited to this, and in other embodiments, the at least two supporting components 10 can be controlled to carry out asynchronous glow discharge when the aeration process and the gas smothering process are carried out in the process chamber 1. In this way, even if the plasma and by-products generated by one supporting component 10 flow to another supporting component 10, the plasma and by-products generated by one supporting component 10 can be annihilated before another supporting component 10 carries out glow discharge, so that the plasma and by-products generated by one supporting component 10 cannot be continuously used for glow discharge to generate plasma by another supporting component 10. Therefore, the uniformity of the plasma in the process chamber 1 can be improved, and the uniformity and quality of the tunnel oxide layer and other thin films prepared can be improved.

[0036] It should be noted that controlling the at least two supporting components 10 to carry out asynchronous glow discharge can only improve the uniformity of the thin films prepared by different supporting components 10, but controlling the circulation in the process chamber 1 to alternately carry out the aeration process and the gas smothering process can not only improve the uniformity of the thin films prepared by different supporting components 10, but also improve the uniformity of the thin films prepared by the same supporting component 10.

[0037] In some embodiments of the present application, referring to FIG. 1, the semiconductor processing equipment further comprises a gas inlet assembly 2 and a gas exhaust assembly 3, the gas inlet assembly 2 is used to introduce process gas into the process chamber 1, and the gas exhaust assembly 3 is used to exhaust the process chamber 1 to control the air pressure in the process chamber 1. Based on this, the control of the alternating process of the process chamber 1 includes: controlling the gas exhaust assembly 3 to exhaust the process chamber 1, and controlling the gas inlet assembly 2 to introduce process gas into the process chamber 1; after the air pressure in the process chamber 1 reaches the first preset air pressure, the gas inlet assembly 2 is controlled to stop introducing process gas into the process chamber 1, and the gas exhaust assembly 3 is controlled to stop exhausting the process chamber 1, so that the flow rate of the gas in the process chamber 1 during the gas soaking process is equal to 0.

[0038] Of course, the present application is not limited to this, in other embodiments, the flow rate of the gas in the process chamber 1 during the gas soaking process can also be greater than 0 and less than a preset flow rate, which can be less than or equal to the flow rate of the gas in the process chamber 1 during the process of introducing gas. It can be understood that as long as the flow rate of the gas in the process chamber 1 during the gas soaking process is less than the flow rate of the gas in the process chamber 1 during the process of introducing gas, the uniformity of the plasma in the process chamber 1 can be improved to a certain extent, the uniformity of the prepared thin film such as tunnel oxide layer can be improved, and the quality of the prepared thin film such as tunnel oxide layer can be improved.

[0039] It should be noted that during the gas soaking process, the deposited thin film will consume the gas in the process chamber 1, and the pressure in the process chamber 1 will decrease, so the pressure in the process chamber 1 can be monitored in real time during this process to determine the end time of the gas soaking process. Of course, the end time of the gas soaking process can also be determined by determining the deposition time in the process chamber 1.

[0040] It should be noted that the number of cycles of the aeration process and the gas soaking process can be determined according to the thickness of the prepared thin film, such as the tunnel oxide layer. If the number of cycles of the aeration process and the gas soaking process is greater than or equal to 2, after each cycle of the aeration process and the gas soaking process is completed, it can be determined whether the air pressure in the process chamber 1 is less than the second preset air pressure or whether the deposition time in the process chamber 1 is greater than or equal to the preset time. If so, the aeration process in the next cycle is performed, that is, the air suction assembly 3 is controlled to perform air suction on the process chamber 1 again, and the air inlet assembly 2 is controlled to introduce the process gas into the process chamber 1 again. Similarly, after the air pressure in the process chamber 1 reaches the first preset air pressure, the air inlet assembly 2 is controlled to stop introducing the process gas into the process chamber 1, and the air suction assembly 3 is controlled to stop air suction on the process chamber 1. If not, the gas soaking process in the current cycle is continued, that is, the state of stopping the introduction of the process gas into the process chamber and stopping the air suction on the process chamber by the air suction assembly is maintained until the air pressure in the process chamber 1 is less than the second preset air pressure or the deposition time in the process chamber 1 is greater than or equal to the preset time.

[0041] It can be understood that the air inlet assembly 2 can be controlled to introduce the process gas into the process chamber 1 after the air suction assembly 3 is controlled to perform air suction on the process chamber 1 so that the air pressure in the process chamber 1 reaches the third preset air pressure, so as to reduce the impurity gas in the process chamber 1.

[0042] In some embodiments of the present application, the first preset air pressure is greater than or equal to 100 Pa and less than or equal to 10,000 Pa; the second preset air pressure is less than or equal to 100 Pa; and the third preset air pressure is less than 10 Pa. Of course, the present application is not limited to this, and in other embodiments, the sizes of the first, second and third preset air pressures can be determined according to the requirements of thin film deposition, which will not be described here.

[0043] In some embodiments of the present application, referring to FIG. 1, the semiconductor process equipment further comprises a power supply assembly 4 configured to provide at least two carrier components 10 with radio frequency signals respectively, and the radio frequency signals are used to excite the process gas in the process chamber 1 to generate glow discharge to produce plasma. As shown in FIG. 4, which is a schematic diagram of the connection relationship between the power supply assembly 4 and the two carrier components 10 according to an embodiment of the present application, taking the case that two carrier components 10 are arranged in the process chamber 1 as an example, the power supply assembly 4 provides the two carrier components 10 with radio frequency signals respectively through two output channels. Based on this, the control of the asynchronous glow discharge of the at least two carrier components 10 comprises: the radio frequency signals provided by the power supply assembly 4 to the at least two carrier components 10 are asynchronous radio frequency signals, wherein the asynchronous radio frequency signals refer to the radio frequency opening time periods of any two radio frequency signals do not overlap, and the radio frequency opening time period is the time period during which the radio frequency signals excite the process gas in the process chamber 1 to generate glow discharge to produce plasma.

[0044] As shown in FIG. 5, the power supply assembly provides two asynchronous RF signals to the two supporting components 10. The RF on period Ton of the RF signal of one supporting component does not overlap with the RF on period Ton of the RF signal of the other supporting component, so that the two supporting components 10 are asynchronously glow-discharged or glow-discharged at different times.

[0045] It can be understood that the RF signal is a periodic signal, and each signal period includes an RF on period Ton and an RF off period Toff. That is, the RF off period Toff is a period in a signal period except the RF on period Ton. In the RF on period Ton, the RF signal excites the process gas in the process chamber 1 to generate glow discharge to produce plasma; in the RF off period Toff, the RF signal does not excite the process gas in the process chamber 1.

[0046] In some embodiments of the present application, the RF signal of any two supporting components 10 among the at least two supporting components 10 has a time delay duration, so that any two supporting components 10 among the at least two supporting components 10 are not glow-discharged at the same time. The time delay duration, for example, refers to the time difference between the rising edge of the first RF on period Ton of one RF signal and the rising edge of the first RF on period Ton of the other RF signal shown in FIG. 5. The time delay duration can be determined according to the time length of the RF on period Ton and the RF off period Toff. Generally, the time delay duration is less than or equal to the time length of the RF on period Ton and greater than or equal to the difference between the time length of the RF off period Toff and the time length of the RF on period Ton.

[0047] It can be understood that the time delay duration can be relatively increased to ensure that the plasma and by-products have sufficient annihilation time. In the case that the gas flow speed in the process chamber 1 is relatively small, the time length of the RF on period Ton or the proportion of the time length of the RF on period Ton relative to the time length of the RF off period Toff can be relatively increased to improve the film deposition rate.

[0048] In some embodiments of the present application, the time length ratio of the RF on period Ton to the RF off period Toff of the RF signal of any supporting component 10 is greater than or equal to 1 / 6 and less than or equal to 1 / 200, so that the time delay duration between the RF signals of any two supporting components 10 is less than or equal to the time length of the RF on period Ton and greater than or equal to the difference between the time length of the RF off period Toff and the time length of the RF on period Ton.

[0049] It should be noted that the ratio of the time length of the RF on period Ton to the RF off period Toff can be set according to the deposition process of different films. For example, the deposited film is a tunneling oxide layer. Since the tunneling oxide layer has a higher requirement for film uniformity, a smaller ratio of the time length of the RF on period Ton to the RF off period Toff is generally used, for example, 1 / 100 or 2 / 50. For example, the deposited film is a polysilicon layer. Since the polysilicon layer has a lower requirement for film uniformity due to its thicker film thickness, a larger ratio of the time length of the RF on period Ton to the RF off period Toff is generally used, for example, 1 / 10.

[0050] For example, the ratio of the time length of the RF on period Ton to the RF off period Toff is 2 / 200, and the time length of the RF on period Ton is equal to 2 ms. The delay time length is greater than or equal to 2 ms and less than or equal to 198 ms. The delay time length is a fixed value between 2 ms and 198 ms. For example, the ratio of the time length of the RF on period Ton to the RF off period Toff is 4 / 40, and the time length of the RF on period Ton is equal to 4 ms. The delay time length is greater than or equal to 4 ms and less than or equal to 36 ms. The delay time length is a fixed value between 4 ms and 36 ms.

[0051] It should be further noted that the power supply assembly 4 in the embodiment of the present application includes a RF power supply and a matcher. The RF power supply provides a RF signal to the carrier component 10 in the process chamber 1 through the matcher. The matcher is used to realize impedance matching between the RF power supply and the carrier component 10. The RF power supply is also connected to a lower computer of a semiconductor process equipment. After the user sets the delay time of the RF signal through the upper computer, the upper computer sends a corresponding control signal to the RF power supply through the lower computer, so that the RF power supply sends the RF signal with the corresponding delay time to the at least two carrier components 10.

[0052] In some embodiments of the present application, the thin film deposition process is described by taking the tunneling oxide layer as an example. First, a plurality of substrates such as silicon wafers with clean surfaces are respectively placed in two carrier components 10 such as graphite boats, the two carrier components 10 are transported into the vacuum process chamber 1 by the transmission device, and the two carrier components 10 are respectively connected to the corresponding electrodes. After the process chamber 1 is tested for vacuum leak detection, the carrier components 10 such as graphite boats and the substrates such as silicon wafers are heated, for example, to 300-500°C, then the gas pressure in the process chamber 1 is controlled by the exhaust assembly 3 to the third preset gas pressure (for example, 10 Pa), and the process gas is introduced into the process chamber 1 by the gas inlet assembly 2. After the gas pressure in the process chamber 1 reaches the first preset gas pressure (for example, 1000 Pa), the gas inlet assembly 2 stops introducing the process gas into the process chamber 1, the exhaust assembly 3 stops the process chamber 1, and the two carrier components 10 are controlled to perform asynchronous glow discharge. The delay time between the two carrier components 10 can be 10 ms, so as to deposit a tunneling oxide layer on the substrate such as a silicon wafer. The process gas for the tunneling oxide layer is laughing gas or oxygen, and the laughing gas is nitrous oxide.

[0053] If the number of cycles of the ventilation process and the gas smothering process is greater than or equal to 2, after the gas pressure in the process chamber 1 is less than the second preset gas pressure or the deposition time in the process chamber 1 is greater than the preset time, the gas pressure in the process chamber 1 is controlled by the exhaust assembly 3 to the third preset gas pressure, or the exhaust assembly 3 is controlled to exhaust the process chamber 1 for a preset time (for example, 15 s), then the process gas is introduced into the process chamber 1 by the gas inlet assembly 2. After the gas pressure in the process chamber 1 reaches the first preset gas pressure, the gas inlet assembly 2 stops introducing the process gas into the process chamber 1, the exhaust assembly 3 stops the process chamber 1, and the two carrier components 10 are controlled to perform asynchronous glow discharge. The cycle is repeated until the thickness of the tunneling oxide layer reaches the preset thickness (for example, 1.5-2.0 nm). During the process of controlling the two carrier components 10 to perform asynchronous glow discharge, the RF frequency of the RF power source can be controlled to be 40 kHz-13.56 MHz, and the RF power can be controlled to be 2 kW-20 kW.

[0054] It should be noted that in the process of preparing a solar cell, after the tunneling oxide layer is prepared, a polysilicon layer and a mask layer will also be prepared. The temperature range for preparing the polysilicon layer and the mask layer can be the same as the temperature range for preparing the tunneling oxide layer (for example, 300-500°C), so as to save process time and improve production efficiency.

[0055] By using the thin film preparation method disclosed in the embodiments of the present application, the uniformity of the thin film prepared by the same carrier component 10 can be controlled within 3%, and the uniformity of the thin film prepared by different carrier components 10 can be controlled within 3%. Compared with the traditional thin film preparation method, the uniformity and quality of the thin film are significantly improved.

[0056] As an implementation form of the disclosure, the semiconductor process equipment disclosed by the embodiments of the present application comprises a process chamber 1, a gas inlet assembly 2, a gas exhaust assembly 3, a power supply assembly 4, and a control assembly (not shown in the figure).

[0057] The process chamber 1 is provided with at least two bearing components 10 for bearing a substrate; the gas inlet assembly 2 is used to introduce process gas into the process chamber 1; the gas exhaust assembly 3 is used to exhaust the process chamber 1 to control the air pressure of the process chamber 1; the power supply assembly 4 is used to provide RF signals to the at least two bearing components 10 respectively. The control assembly comprises at least one memory and at least one processor, the memory stores a computer program, and the processor is used to execute the computer program to realize the thin film preparation method disclosed in any of the above embodiments.

[0058] In some embodiments of the present application, as shown in Figure 6, the gas inlet assembly 2 comprises a first valve 20, and the gas exhaust assembly 3 comprises a second valve 31. The first valve 20 is arranged on the gas path between the gas supply component and the process chamber 1, and is used to control the opening or closing of the gas path between the gas supply component and the process chamber 1. The second valve 31 is arranged on the gas path between the vacuum pump 33 and the process chamber 1, and the vacuum pump 33 is used to exhaust the process chamber 1. The second valve 31 is used to control the opening or closing of the gas path between the vacuum pump 33 and the process chamber 1. The gas supply component can be a factory gas supply component. The first valve 20 includes but is not limited to a pneumatic valve, and the second valve 31 includes but is not limited to a butterfly valve.

[0059] Therefore, by controlling the opening of the first valve 20, the gas inlet assembly 2 can be controlled to introduce process gas into the process chamber 1. By controlling the opening of the second valve 31, the gas exhaust assembly 3 can be controlled to exhaust the process chamber 1. By controlling the closing of the first valve 20, the gas inlet assembly 2 can be controlled to stop introducing process gas into the process chamber 1. By controlling the closing of the second valve 31, the gas exhaust assembly 3 can be controlled to stop exhausting the process chamber 1.

[0060] It should be noted that the gas exhaust assembly 3 further comprises a vacuum gauge 32 for measuring the pressure in the process chamber 1, so as to adjust the opening of the second valve 31 according to the measurement result of the vacuum gauge 32, and further adjust the pressure in the process chamber 1. The gas inlet assembly 2 further comprises a gas mass flow meter 21 for measuring the gas flow in the gas path between the gas supply component and the process chamber 1, so as to adjust the opening of the first valve 20 according to the measurement result of the gas mass flow meter 21, and further adjust the gas pressure in the process chamber 1.

[0061] In some other embodiments of the present application, the gas inlet assembly 2 further comprises a regulating valve 22 and a hand valve 23. The regulating valve 22 is used to regulate the pressure of the gas path between the gas supply component and the process chamber 1, and the hand valve 23 is used to open or close the gas path between the gas supply component and the process chamber 1. When the process gas is introduced into the process chamber 1 by controlling the gas inlet assembly 2, not only the first valve 20 is opened, but also the regulating valve 22 and the hand valve 23 are opened.

[0062] Of course, the present application is not limited to this, and in some other embodiments, as shown in FIG. 7, which is a schematic structural diagram of another gas inlet assembly disclosed by embodiments of the present application, the gas inlet assembly 2 can further comprise a gas buffer component 24 and a gas path control component 25.

[0063] The gas buffer component 24 is arranged between the gas supply component and the process chamber 1, and specifically arranged between the gas supply component and the first valve 20. The gas buffer component 24 is used to buffer the process gas provided by the gas supply component, and transmit the process gas to the process chamber 1 when the gas path between the gas buffer component 24 and the process chamber 1 is opened. The speed of the process gas transmitted to the process chamber 1 by the gas buffer component 24 is greater than the speed of the process gas transmitted to the gas buffer component 24 by the gas supply component, so as to realize the rapid aeration of the process chamber 1, reduce the process time, improve the production efficiency, and reduce the production cost.

[0064] The gas path control component 25 is arranged between the gas supply component and the gas buffer component 24, and the gas path control component 25 is used to control the opening or closing of the gas path between the gas supply component and the gas buffer component 24. The gas path control component 25 includes but is not limited to a pneumatic valve.

[0065] On the basis of the above-mentioned embodiments, as shown in FIG. 7, the gas inlet assembly 2 further comprises a pressure measuring component 26 in some embodiments of the present application. The pressure measuring component 26 is arranged on the gas buffer component 24, and specifically can be arranged inside the gas buffer component 24, and is used to measure the gas pressure inside the gas buffer component 24, so as to control the gas path control component 25 according to the measurement result.

[0066] Specifically, the control component can send a first control instruction to the gas path control component 25 when the gas pressure inside the gas buffer component 24 rises to a fourth preset gas pressure (such as 20 psi), and control the gas path between the gas buffer component 24 and the gas supply component to be closed; and send a second control instruction to the gas path control component 25 when the gas pressure inside the gas buffer component 24 drops to a fifth preset gas pressure, and control the gas path between the gas buffer component 24 and the gas supply component to be opened. The fifth preset gas pressure is less than the fourth preset gas pressure.

[0067] On the basis of the above-mentioned embodiments, as shown in FIG. 7, the gas inlet assembly 2 further comprises a first one-way control component 27, a second one-way control component 28 and a hand control component 29 in some embodiments of the present application.

[0068] The first one-way control component 27 is arranged between the gas supply component and the gas path control component 25, and is used to control the flow direction of the gas to be a single direction, preventing the gas in the gas buffer component 24 from flowing back to the gas supply component. The first one-way control component 27 includes but is not limited to a one-way valve.

[0069] The second one-way control component 28 is arranged between the gas buffer component 24 and the process chamber 1, and specifically between the first valve 20 and the process chamber 1, and is used to control the flow direction of the gas to be a single direction, preventing the gas in the process chamber 1 from flowing back to the gas supply component. The second one-way control component 28 includes but is not limited to a one-way valve.

[0070] The manual control component 29 is arranged between the first one-way control component 27 and the gas path control component 25, and is used to control the gas path between the gas path control component 25 and the gas supply component. The manual control component 29 includes but is not limited to a hand valve.

[0071] It can be understood that by arranging the first one-way control component 27, the second one-way control component 28 and the manual control component 29, the safety of the gas path and the equipment can be further enhanced.

[0072] It should be noted that before the deposition of the thin film, the gas path control component 25, the regulating valve 22, the hand valve 23 and the manual control component 29 can be controlled to be opened, so that the gas supply component fills the gas buffer component 24 with gas, and when the gas pressure in the gas buffer component 24 rises to the fourth preset gas pressure, the gas path control component 25 is controlled to be closed. During the deposition of the thin film, the first valve 20 is controlled to be opened, and the process gas in the gas buffer component 24 is quickly introduced into the process chamber 1 by using the pressure difference between the gas buffer component 24 and the process chamber 1, and according to the gas pressure in the process chamber 1 displayed by the vacuum gauge, when the gas pressure in the process chamber 1 reaches the first preset gas pressure, the first valve 20 is controlled to be closed.

[0073] The technical features of the above embodiments can be combined in any manner. In order to make the description concise, all possible combinations of the technical features in the above embodiments are not described, but as long as the combinations of the technical features do not exist contradictions, they should be considered as the scope of the present disclosure.

[0074] The above embodiments only express several implementation manners of the present disclosure, and the description is specific and detailed, but it should not be understood as a limitation on the patent scope. It should be noted that for ordinary skilled persons in the art, some modifications and improvements can be made without departing from the concept of the present disclosure, and these all belong to the protection scope of the present disclosure. Therefore, the patent protection scope of the present disclosure should be subject to the appended claims.

Claims

1. A method of making a film, characterized by, The application is applied to a semiconductor process equipment, which comprises a process chamber, at least two supporting components are arranged in the process chamber, and the supporting components are used for supporting substrates. The method comprises the following steps: After the plurality of substrates are respectively placed in the at least two supporting components, the process chamber is controlled to alternately perform a ventilation process and a gas retention process, and the at least two supporting components are controlled to perform asynchronous glow discharge at least when the process chamber performs the gas retention process. The ventilation process is used for ventilating the process chamber with process gas required for depositing a film. The flow speed of the gas in the process chamber when the gas retention process is performed is less than the flow speed of the gas in the process chamber when the ventilation process is performed.

2. The method of claim 1, wherein The semiconductor process equipment further comprises a gas inlet assembly and a gas exhaust assembly. The gas inlet assembly is used for ventilating the process chamber with process gas. The gas exhaust assembly is used for exhausting the process chamber to control the air pressure in the process chamber. The control of the process chamber to alternately perform the ventilation process and the gas retention process comprises the following steps: The gas exhaust assembly is controlled to exhaust the process chamber, and the gas inlet assembly is controlled to ventilate the process chamber with process gas. When the air pressure in the process chamber reaches a first preset air pressure, the gas inlet assembly is controlled to stop ventilating the process chamber with process gas, and the gas exhaust assembly is controlled to stop exhausting the process chamber.

3. The method of claim 2, wherein the film is prepared by a method comprising: The first preset air pressure is greater than or equal to 100 Pa and less than or equal to 10,000 Pa.

4. The method of claim 1, wherein The semiconductor process equipment further comprises a power supply assembly, which is used for providing the at least two supporting components with radio frequency signals respectively, and the radio frequency signals are used for exciting the process chamber to perform glow discharge to generate plasma. The control of the at least two supporting components to perform asynchronous glow discharge comprises the following steps: The power supply assembly is controlled to provide the at least two supporting components with radio frequency signals with non-overlapping radio frequency opening time periods. The radio frequency opening time period is a time period in which the radio frequency signals excite the process chamber to perform glow discharge to generate plasma.

5. The method of claim 4, wherein the film is prepared by a method comprising: The radio frequency signals of any two supporting components among the at least two supporting components have a time delay. The time delay is greater than or equal to the length of the radio frequency opening time period and less than or equal to the difference between the length of the radio frequency opening time period and the length of a radio frequency closing time period. The radio frequency closing time period is a time period in a signal cycle except the radio frequency opening time period.

6. The method of claim 5, wherein the film is prepared by a method comprising: The length ratio of the radio frequency opening time period to the radio frequency closing time period of the radio frequency signal of any supporting component is greater than or equal to 1 / 6 and less than or equal to 1 / 200.

7. A semiconductor process apparatus characterized by comprising: The semiconductor process equipment comprises a process chamber, a gas inlet assembly, a gas exhaust assembly, a power supply assembly and a control assembly. The process chamber is provided with at least two supporting components, which are used for supporting substrates. The gas inlet assembly is used for ventilating the process chamber with process gas. The gas exhaust assembly is used for exhausting the process chamber to control the air pressure in the process chamber. The power supply assembly is used for providing the at least two supporting components with radio frequency signals respectively. The control assembly comprises at least one memory and at least one processor, the memory stores a computer program, and the processor is configured to execute the computer program to implement the thin film preparation method of any one of claims 1-6.

8. The semiconductor process apparatus according to claim 7, wherein The gas inlet assembly comprises a gas buffering component and a gas path control component; The gas buffering component is arranged between the gas supply component and the process chamber, and is configured to buffer the process gas supplied by the gas supply component and transmit the process gas to the process chamber when the gas path between the gas buffering component and the process chamber is opened; the speed of the process gas transmitted by the gas buffering component to the process chamber is greater than the speed of the process gas transmitted by the gas supply component to the gas buffering component; The gas path control component is arranged between the gas buffering component and the gas supply component, and is configured to control the opening or closing of the gas path between the gas buffering component and the gas supply component.

9. The semiconductor process apparatus according to claim 8, wherein The gas inlet assembly further comprises a pressure measuring component; The pressure measuring component is arranged on the gas buffering component and is configured to measure the gas pressure inside the gas buffering component.

10. The semiconductor process apparatus according to claim 9, wherein The gas inlet assembly further comprises a first one-way control component, a second one-way control component and a manual control component; The first one-way control component is arranged between the gas supply component and the gas path control component, the second one-way control component is arranged between the gas buffering component and the process chamber, and the manual control component is arranged between the first one-way control component and the gas path control component.

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