Semiconductor cleaning equipment and cleaning method

Abstract

The invention provides semiconductor cleaning equipment and a cleaning method.The semiconductor cleaning equipment comprises a rack, a process pipe, a fixing support, a radio frequency induction coil and a driving device, a cavity is formed in the process pipe, and the cavity is used for containing a graphite boat to be cleaned; the fixed bracket is connected with the rack and can move relative to the rack; the radio frequency induction coil is wound on the periphery of the process pipe, each turn of wire of the radio frequency induction coil is fixed on the fixed support, and the radio frequency induction coil is used for enabling process gas in the process pipe to form plasma; the driving device is used for driving the fixing support to move in the first direction so as to drive the radio frequency induction coil to move relative to the process pipe in the first direction. Wherein the first direction is parallel to the length direction of the process pipe. When the semiconductor cleaning equipment is used for cleaning the graphite boat, the radio frequency induction coil surrounds part of the process pipe, so that the graphite boat is cleaned in a segmented manner, and the cleaning time is short.

Description

Technical Field

[0001] The present invention relates to the field of photovoltaic technology, and in particular to a semiconductor cleaning device and a cleaning method. Background Art

[0002] In the process of preparing crystalline silicon solar cells, the anti-reflection film and / or passivation film on the surface of the silicon wafer is generally achieved by plasma enhanced chemical vapor deposition (PECVD) equipment, specifically using a graphite boat to load the silicon wafer into the reaction chamber for coating. During the process, the graphite boat and the silicon wafer are both located in the reaction chamber, and reaction byproducts will be deposited on the graphite boat. If the reaction byproducts are too thick, the impedance of the graphite boat will change, and there will be deviations in the subsequent process, which will affect the efficiency of the cell. Therefore, the graphite boat needs to be cleaned regularly.

[0003] Currently, dry cleaning technology is usually used to clean graphite boats. Figure 1 A schematic diagram of a semiconductor cleaning device in the related art is shown. Figure 1 The semiconductor cleaning device 100a shown includes a process tube 20a, a graphite boat 200 to be cleaned is placed inside the process tube 20a, a process gas is introduced into the process tube 20a, a radio frequency induction coil 30a is arranged around the outer circumference of the process tube, and the radio frequency induction coil 30a roughly wraps the entire process tube 20a. The semiconductor cleaning device 100a uses inductively coupled plasma technology (Inductive Coupled Plasma Emission Spectrometer, ICP) to clean the graphite boat 200.

[0004] However, when the graphite boat is cleaned in this manner, the cleaning time is long. Summary of the invention

[0005] The present invention aims to solve at least one of the technical problems existing in the prior art, and proposes a semiconductor cleaning device and a cleaning method.

[0006] In order to achieve the purpose of the present invention, a semiconductor cleaning device is provided. The semiconductor cleaning device includes a frame, a process tube, a fixed bracket, a radio frequency induction coil and a driving device. The process tube has a cavity inside, and the cavity is used to accommodate a graphite boat to be cleaned; the fixed bracket is connected to the frame and can move relative to the frame; the radio frequency induction coil is wound around the outer circumference of the process tube, and each turn of the radio frequency induction coil is fixed on the fixed bracket. The radio frequency induction coil is used to make the process gas in the process tube form plasma;

[0007] The driving device is used to drive the fixed support to move along a first direction, so as to drive the radio frequency induction coil to move along the first direction relative to the process tube; wherein the first direction is parallel to the length direction of the process tube.

[0008] The semiconductor cleaning equipment as described above, wherein the length of the RF induction coil is less than a quarter of the wavelength of the RF signal applied to the RF induction coil.

[0009] In the semiconductor cleaning equipment as described above, the length of the radio frequency induction coil is less than one tenth of the wavelength of the radio frequency signal.

[0010] The semiconductor cleaning equipment as described above, wherein the semiconductor cleaning equipment also includes a radio frequency power supply arranged outside the process tube, and the radio frequency power supply is used to output a radio frequency signal; the two ends of the radio frequency induction coil are respectively an input end and a ground end; the semiconductor cleaning equipment also includes a first connector and a second connector installed on a fixed bracket, the first connector is connected to the input end, the second connector is connected to the ground end, and the first connector and the second connector are respectively electrically connected to the radio frequency power supply through flexible cables.

[0011] In the semiconductor cleaning equipment as described above, there are two fixed brackets, which are arranged opposite to each other, and the process tube is located between the two fixed brackets; the first connector and the second connector are arranged on the same fixed bracket.

[0012] In the semiconductor cleaning equipment as described above, there is a gap between the radio frequency induction coil and the outer surface of the process tube.

[0013] In the semiconductor cleaning equipment as described above, the dimension of the gap along the radial direction of the process tube is greater than or equal to 10 mm and less than or equal to 50 mm.

[0014] The semiconductor cleaning equipment as described above, wherein the fixed bracket includes a metal mounting plate and an insulating plate, the insulating plate is fixedly connected to the metal mounting plate, and each turn of the RF induction coil is fixed on a side of the insulating plate facing the process tube to insulate the RF induction coil from the metal mounting plate.

[0015] In the semiconductor cleaning equipment as described above, a plurality of limiting spaces are formed on a surface of the insulating plate facing the process tube, and each turn of the conductor of the radio frequency induction coil is correspondingly arranged in a limiting space, so that the displacement of each turn of the conductor along the thickness direction of the insulating plate is limited.

[0016] The semiconductor cleaning equipment as described above, wherein the metal mounting plate is recessed in a direction away from the process tube to form a groove, the insulating plate is located in the groove, and the thickness of the insulating plate is equal to the depth of the groove; and / or the fixed bracket also includes a plurality of limit plates, at least one end of the limit plate along the first direction is fixedly connected to a side of the insulating plate facing the process tube, and the limit plate and the insulating plate together enclose a limit space.

[0017] As described above, the semiconductor cleaning equipment, wherein a plurality of slideways are provided on the frame, and the slideways extend along a first direction; sliders are provided at both ends of the metal mounting plate along a second direction, and each slider slides in cooperation with a corresponding slideway; wherein the second direction is perpendicular to the first direction and the thickness direction of the metal mounting plate.

[0018] The semiconductor cleaning equipment as described above, wherein the driving device includes a driving motor and a transmission device, the driving motor is arranged on a frame, and the transmission device is used to convert the rotational power of the driving motor into linear power and transmit it to the metal mounting plate to drive the metal mounting plate to move along a first direction.

[0019] The semiconductor cleaning equipment as described above, wherein the semiconductor cleaning equipment also includes a connecting support, a motor support and a supporting support, the connecting support is fixedly connected to the frame, one end of the supporting support is connected to the connecting support and the other end is connected to the motor support, and the driving motor is fixedly arranged on the motor support.

[0020] As described above, the semiconductor cleaning equipment, wherein the frame includes a main frame and a partition frame, the main frame is a rectangular frame structure, the partition frame is a rectangular frame structure, the partition frame is arranged in the main frame to separate the main frame into a first space and a second space, the process pipe is located in the first space, and the connecting support, the motor support and the supporting support are all located in the second space.

[0021] The semiconductor cleaning equipment as described above, wherein the transmission device includes a synchronous shaft, a driving pulley, a driven pulley and a conveyor belt, the synchronous shaft is connected to the motor shaft of the driving motor, the driving pulley is mounted on the synchronous shaft, the driven pulley is rotatably connected to the frame, the rotation axis of the driven pulley is parallel to the rotation axis of the synchronous shaft, and the conveyor belt is wound between the driving pulley and the driven pulley; a transmission member is fixedly arranged on the conveyor belt, and the transmission member is fixedly connected to the metal mounting plate.

[0022] As another technical solution, the present invention further provides a cleaning method, which is applied to any of the above-mentioned semiconductor cleaning devices provided by the present invention, and the cleaning method comprises:

[0023] Placing a graphite boat to be cleaned into a cavity of a process tube; wherein the graphite boat has a plurality of boat sections sequentially arranged along a first direction;

[0024] a boat cleaning step, controlling the driving device to drive the fixed support to move relative to the process tube in a first direction, so as to drive the RF induction coil to move along the first direction to the periphery surrounding one of the boat segments, applying RF power to the RF induction coil so that the process gas in the chamber forms plasma, and maintaining the position of the RF induction coil within a preset time, so that the boat segment is cleaned;

[0025] The boat cleaning step is repeated until all of the boats are cleaned.

[0026] In the cleaning method as described above, the RF induction coil is initially arranged around the outer circumference of a boat segment close to the furnace mouth of the process tube; when all the boat segments are cleaned, each of the boat segments is cleaned sequentially from the furnace mouth of the process tube to the furnace tail of the process tube.

[0027] In the cleaning method as described above, the RF induction coil is initially arranged around the outer circumference of a boat segment close to the furnace tail of the process tube; when all the boat segments are cleaned, each boat segment is cleaned sequentially from the furnace tail of the process tube to the furnace mouth of the process tube.

[0028] The cleaning method as described above, wherein, after the boat cleaning step and before repeating the boat cleaning step, the cleaning method further comprises: stopping loading RF power to the RF induction coil.

[0029] The present invention has the following beneficial effects:

[0030] The semiconductor cleaning equipment provided by the present invention is designed to have a shorter length of the radio frequency induction coil, so that the radio frequency induction coil can only surround the outer periphery of part of the graphite boat, and the radio frequency induction coil is driven to move by a driving device to clean the graphite boat in sections, which can effectively avoid the long cleaning time caused by the high resistance value due to the excessive length of the radio frequency induction coil. In this way, under the premise of ensuring that the entire graphite boat can be cleaned, the length of the radio frequency induction coil in this embodiment is short, the resistance value of the radio frequency induction coil is low, the current on the radio frequency induction coil is high, the concentration of the plasma formed by the electromagnetic field generated by the radio frequency induction coil is high, and the time required to clean the graphite boat is short. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 A schematic diagram of a semiconductor cleaning device in the related art;

[0032] Figure 2 A schematic diagram of the structure of a semiconductor cleaning device provided in an embodiment of the present application;

[0033] Figure 3 A side view of a semiconductor cleaning device provided in an embodiment of the present application;

[0034] Figure 4 A schematic diagram of the working process of a semiconductor cleaning device provided in an embodiment of the present application;

[0035] Figure 5 A schematic diagram of the coordination of a fixed support, a radio frequency induction coil and a process tube in a semiconductor cleaning device provided in an embodiment of the present application;

[0036] Figure 6 A partial schematic diagram of the cooperation between a fixed support and a radio frequency induction coil in a semiconductor cleaning device provided in an embodiment of the present application;

[0037] Figure 7 for Figure 2 A partial enlarged view of A in the semiconductor cleaning equipment shown;

[0038] Figure 8 for Figure 2 A partial enlarged view of position B in the semiconductor cleaning equipment shown;

[0039] Fig. 9 A schematic diagram of a cleaning method provided in an embodiment of the present application.

[0040] Description of reference numerals:

[0041] 100-Semiconductor cleaning equipment;

[0042] 10-frame; 11-main frame; 12-partition frame;

[0043] 20-process tube; 21-rod body; 22-furnace door;

[0044] 30-RF induction coil;

[0045] 40-RF power supply; 41-flexible cable; 42-first connector; 43-second connector;

[0046] 50-fixed bracket; 51-metal mounting plate; 511-flange; 52-insulating plate; 53-limiting plate; 54-connecting plate; 55-slider;

[0047] 60-driving motor; 61-conveyor belt; 611-transmission member; 612-pressing plate; 63-driving pulley;

[0048] 64-supporting support; 65-motor support; 66-connecting support;

[0049] 70-guide rail;

[0050] 200-Graphite boat. DETAILED DESCRIPTION

[0051] The following embodiments of the present application provide a semiconductor cleaning device, which is used to clean a graphite boat. The cleaning method adopted is dry cleaning. Compared with wet cleaning, the dry cleaning method has the advantages of less pollution to the environment and no need to disassemble the graphite boat to avoid mechanical damage to the graphite boat due to disassembly.

[0052] The semiconductor cleaning equipment specifically uses inductively coupled plasma technology for cleaning. The cleaning principle is as follows: a process gas is introduced into the process tube, and the process gas contains fluorine-based gases such as NF3, CF4 or C2F6 and oxygen. The radio frequency induction coil wound around the outer periphery of the process tube is loaded with radio frequency power to generate a high-frequency electromagnetic field. The electromagnetic field generates an induced electric field inside the process tube to dissociate the fluorine-based gas into plasma. In the following, NF3 is taken as an example. Specifically, the electron e - Under the action of the induced electric field, the electron e - During the movement, it reacts with NF3 according to the following formula (I), and NF3 is bombarded to produce fluorine free radicals (F * ), NF2 and electrons e - NF2 will react with electrons e - According to the following formula (II), NF2 is bombarded to produce fluorine free radicals (F * ), NF and electronic - NF will be with the electron e - According to the following formula (III), the NF is bombarded to produce fluorine free radicals (F * ), N2 and electrons e - .

[0053] e - +NF3→NF2+F*+e - Formula (I)

[0054] e - +NF2→NF+F*+e - Formula (II)

[0055] e - +NF→N2+F*+e - Formula (III)

[0056] In general, the fluorine-based gas in the process gas is excited into plasma F * The reaction byproducts on the graphite boat are silicon nitride SiN, plasma F * It reacts with SiN according to the following formula (IV) to obtain gaseous SiF4, which is discharged out of the process pipe, thereby achieving the cleaning of the graphite boat.

[0057] F*+SiN→SiF4↑+N2 Formula (IV)

[0058] It can be understood that during the graphite boat cleaning process, the uniformity of plasma is an important indicator affecting the cleaning quality. The uniformity of plasma is closely related to the uniformity of the electromagnetic field distribution in the process tube.

[0059] use Figure 1 When the semiconductor cleaning device 100a shown is used to clean the graphite boat 200, the cleaning time is relatively long. After careful research, the inventor of the present application found that one of the reasons for this problem is that since the RF induction coil 30a can almost wrap the entire process tube 20a, the RF induction coil 30a is relatively long, and the resistance is high, which in turn leads to a relatively small current on the RF induction coil 30a, so the concentration of the generated plasma is low and the cleaning time is long.

[0060] Another reason for this problem is that the output impedance of the RF power supply that provides RF power to the RF induction coil 30a is generally 50 ohms. The RF induction coil 30a is limited by the manufacturing process, so its impedance is difficult to reach 50 ohms. The impedance of the RF power supply and the RF induction coil 30a does not match, which causes the electromagnetic waves formed by the propagation of the electromagnetic field to be reflected.

[0061] The RF power supply outputs a sine wave, and the RF signal is usually a high-frequency signal with a shorter wavelength. If the operating frequency of the RF signal is set to 13.56MHz, the wavelength of the RF signal is approximately 22m. Figure 1 In the example shown, the RF induction coil 30a is wound from one end of the process tube 20a to the other end, and the length of the RF induction coil 30a is much greater than one quarter of the wavelength of the RF signal. In this way, the incident wave and the reflected wave will be superimposed to form a standing wave, and a standing wave effect will be generated on the RF induction coil 30a, resulting in different currents at various locations on the RF induction coil 30a, which in turn causes the electromagnetic field generated by the RF induction coil 30a to be unevenly distributed, and the distribution uniformity of the plasma in the process tube 20a is affected. Specifically, the magnetic field intensity of the electromagnetic field corresponding to the smaller current on the RF induction coil 30a is small, and the plasma density in the area with smaller magnetic field intensity in the process tube 20a is low, so the cleaning effect of the part of the graphite boat 200 located in this area is not good. In order to ensure that all parts of the graphite boat 200 can meet the cleaning requirements, the cleaning process will not reach the end until the part of the graphite boat 200 located in the area with smaller magnetic field intensity is cleaned, so the cleaning time is long.

[0062] Based on this, the embodiment of the present application provides a semiconductor cleaning device and a cleaning method, by designing a RF induction coil surrounding a part of the process tube to be movable, so as to clean the graphite boat in sections. In order to enable those skilled in the art to better understand the technical solution of the present invention, the semiconductor cleaning device and the cleaning method provided by the present invention are described in detail below in conjunction with the accompanying drawings.

[0063] Figure 2 A schematic diagram of the structure of a semiconductor cleaning device provided in an embodiment of the present application is shown in FIG. Figure 3 This is a side view of a semiconductor cleaning device provided in an embodiment of the present application. Please refer to Figure 2 and Figure 3 As shown, the semiconductor cleaning equipment 100 includes a frame 10 , a process tube 20 , an air intake assembly, an air extraction assembly, a radio frequency induction coil 30 , and a radio frequency power supply 40 disposed outside the process tube 20 .

[0064] The process tube 20 has a cavity inside for accommodating the graphite boat 200 to be cleaned. The process tube 20 is arranged along a first direction (in Figure 2 One end of the furnace (X) is the furnace mouth and the other end is the furnace tail. Exemplarily, both the furnace mouth and the furnace tail can be opened. At this time, the furnace door 22 can be movably connected at the furnace mouth and the furnace tail of the process tube 20, so that the furnace mouth and the furnace tail can be opened and closed. When the graphite boat 200 needs to be cleaned, the furnace door 22 at the furnace mouth or the furnace door 22 at the furnace tail is opened, and the graphite boat 200 to be cleaned is introduced into the cavity by a manipulator, and then the furnace door 22 is closed, so that the cavity is sealed and reaches a vacuum state for the cleaning process. After the cleaning process is completed, the furnace door 22 at the furnace mouth or the furnace door 22 at the furnace tail is opened, and the cleaned graphite boat 200 is taken out by a manipulator. In order to improve the sealing of the cavity, a sealing ring can be provided between the furnace door 22 and the furnace mouth, and between the furnace door 22 and the furnace tail, so that the furnace door 22 is in sealing contact with the process tube 20.

[0065] Of course, in some embodiments, the furnace tail of the process tube 20 may be closed and only the furnace mouth is open. In this case, only the furnace mouth is provided with a furnace door 22 to open and close the furnace mouth. The process tube 20 may be made of quartz or ceramic material, for example.

[0066] The semiconductor cleaning equipment 100 further includes a plurality of rods 21, which are located inside the process tube 20 and extend along the first direction X. One end of the rod 21 extends to the furnace mouth, and the other end extends to the furnace tail. Both ends of the rod 21 are connected to the process tube 20. The rod 21 can be used to carry the graphite boat 200, so that the graphite boat 200 is placed on the rod 21. The rod 21 can be made of silicon carbide (SiC), for example.

[0067] The air intake assembly includes an air source and an air intake pipeline. The air source is arranged outside the process pipe 20. One end of the air intake pipeline is connected to the air source and the other end is connected to the inside of the process pipe 20 to introduce process gas into the cavity. The air extraction assembly includes an air extraction pump and an exhaust pipeline. The air extraction pump is arranged outside the process pipe 20. One end of the exhaust pipeline is connected to the inside of the process pipe 20 and the other end is connected to the air extraction pump to extract the gas in the cavity.

[0068] The RF induction coil 30 is wound around the outer circumference of the process tube 20, and the two ends of the RF induction coil 30 are respectively an input end and a ground end, and the input end and the ground end are respectively electrically connected to the RF power supply 40. In this way, the RF power supply 40 loads RF power to the RF induction coil 30, thereby generating a high-frequency electromagnetic field in the process tube 20, and the high-frequency electromagnetic field generates an induced electric field inside the process tube 20 to dissociate the fluorine-based gas into plasma, thereby achieving cleaning of the graphite boat 200.

[0069] It should also be pointed out that in this embodiment, the RF induction coil 30 only surrounds the outer circumference of a portion of the process tube 20, so that an electromagnetic field is generated in a portion of the cavity within the process tube 20, and the electromagnetic field excites the process gas in the corresponding area to form plasma, so that a portion of the graphite boat 200 located in the area is cleaned.

[0070] On this basis, the semiconductor cleaning equipment 100 also includes a fixed bracket 50 and a driving device. The fixed bracket 50 is connected to the frame 10 and can move relative to the frame 10. Each turn of the wire of the RF induction coil 30 is fixed on the fixed bracket 50. The driving device is used to drive the fixed bracket 50 to move along the first direction X, so as to drive the RF induction coil 30 to move along the first direction X relative to the process tube 20.

[0071] Here, the graphite boat 200 can be regarded as having N boat segments arranged in sequence along the first direction X, where N is a positive integer greater than or equal to 2. For the convenience of description, from the furnace mouth to the furnace tail of the process tube 20, the N boat segments can be respectively referred to as the first boat segment, ..., the Nth boat segment. The RF induction coil 30 is driven to move by a driving device, and the RF induction coil 30 can change its position to move to the periphery of each boat segment in sequence, so that each boat segment is cleaned in sequence, thereby achieving the cleaning of the entire graphite boat 200. It should be noted that the number of boat segments N is related to the number of turns n of the RF induction coil 30 and the length of the RF induction coil 30. Specifically, the more turns n there are, the longer the length of the RF induction coil 30 is, the longer the portion of the graphite boat 200 surrounded by the RF induction coil 30 is, the smaller the number of boat segments N is, and the fewer times the RF induction coil 30 moves during the entire cleaning process; the fewer turns n there are, the smaller the length of the RF induction coil 30 is, the shorter the portion of the graphite boat 200 surrounded by the RF induction coil 30 is, the larger the number of boat segments N is, and the more times the RF induction coil 30 moves during the entire cleaning process.

[0072] Figure 4 A schematic diagram of the working process of a semiconductor cleaning device 100 provided in an embodiment of the present application. Assuming that the number of turns n of the RF induction coil 30 is 4, and the portion surrounded by the 4-turn RF induction coil 30 accounts for 1 / 3 of the total length of the graphite boat 200 along the first direction X, the number of boat segments N is 3. Please refer to Figure 4In this embodiment, an exemplary working process of the semiconductor cleaning device 100 is as follows:

[0073] In the initial state, the RF induction coil 30 is close to the furnace opening of the process tube 20, such as Figure 4 As shown in a, the center of the RF induction coil 30 is located at 1 / 6 of the length of the graphite boat 200, and the RF induction coil 30 surrounds the first boat segment. The RF induction coil 30 is energized, and a portion of the cavity corresponding to the first boat segment is excited to form plasma to clean the first boat segment; after a certain time t, the first boat segment is cleaned; and the RF induction coil 30 is powered off.

[0074] The driving device drives the fixed support 50 to move along the first direction X, so as to drive the RF induction coil 30 to move to the middle of the process tube 20. Figure 4 As shown in b, the center of the RF induction coil 30 is located at 1 / 2 of the length of the graphite boat 200, and the RF induction coil 30 surrounds the second boat segment. The RF induction coil 30 is energized, and a portion of the cavity corresponding to the second boat segment is excited to form plasma to clean the second boat segment; after a certain period of time t, the second boat segment is cleaned; and the RF induction coil 30 is powered off.

[0075] The driving device then drives the fixed support 50 to move along the first direction X, so as to drive the RF induction coil 30 to move close to the furnace tail of the process tube 20. Figure 4 As shown in FIG. 3 , the center of the RF induction coil 30 is located at 5 / 6 of the length of the graphite boat 200, and the RF induction coil 30 surrounds the third boat segment. The RF induction coil 30 is energized, and a plasma is excited in a part of the cavity corresponding to the third boat segment to clean the third boat segment. After a certain time t, the third boat segment is cleaned, and the entire graphite boat 200 is cleaned, and the cleaning process is completed.

[0076] The RF power supply 40 no longer loads RF power to the RF induction coil 30, and the air intake assembly introduces atmosphere into the cavity until the cavity changes from a vacuum state to a non-vacuum state. The furnace door 22 moves relative to the process tube 20 to open the furnace mouth, and the robot takes the cleaned graphite boat 200 out of the furnace mouth.

[0077] In summary of the above description, the semiconductor cleaning equipment 100 of this embodiment is designed to surround the outer side of a part of the process tube 20 by designing the RF induction coil 30, so that only the part of the cavity surrounded by the RF induction coil 30 can generate an electromagnetic field, and the RF induction coil 30 is driven to move by the driving device to clean the graphite boat 200 in sections. Therefore, under the premise of ensuring that the entire graphite boat 200 can be cleaned, the length of the RF induction coil 30 in this embodiment is relatively small, and the resistance R of the RF induction coil 30 is low, which can effectively avoid the extension of the cleaning time caused by the high resistance due to the excessive length of the RF induction coil 30.

[0078] Thus, the semiconductor cleaning apparatus 100 of this embodiment is combined with Figure 1 Compared with the semiconductor cleaning device 100a shown in FIG. 1 , if the RF power P of the RF power source 40 is the same, according to the thermal power formula of the resistor, P=I 2 R, it can be understood that in this embodiment, the current I on the RF induction coil 30 is higher, and the concentration of the plasma formed by the electromagnetic field generated by the RF induction coil 30 is higher. Under the condition that the cleaning degree of the graphite boat 200 is the same, the time required for cleaning the graphite boat 200 using the semiconductor cleaning equipment 100 of this embodiment is relatively short.

[0079] In some embodiments, the length of the RF induction coil 30 is less than one quarter of the wavelength of the RF signal output by the RF power source 40. Exemplarily, the RF frequency of the RF signal may be 2 MHz, and the wavelength of the RF signal is 150 m, so the length L of the RF induction coil 30 needs to be less than 37.5 m. Assuming that the diameter d of the RF induction coil 30 is 0.6 m, according to L=πdn, considering that there is a certain distance between two adjacent turns of the wire, the number of turns n of the RF induction coil 30 is ≤19.9.

[0080] In this embodiment, the length of the RF induction coil 30 is designed to be less than one-fourth of the wavelength of the RF signal, so that the length of the RF induction coil 30 is small. Moreover, by designing the length of the RF induction coil 30 to be less than one-fourth of the wavelength of the RF signal, it is helpful to avoid the standing wave effect on the RF induction coil 30, so that the currents at various locations on the RF induction coil 30 are as uniform as possible, thereby improving the uniformity of the electromagnetic field, thereby improving the uniformity of the plasma distribution, and improving the cleaning quality. Based on this, under the premise that each boat section of the graphite boat 200 meets the cleaning requirements, the time required for cleaning using the semiconductor cleaning equipment 100 of this embodiment is short.

[0081] In this embodiment, it is not only possible to effectively avoid prolonging the cleaning time due to high resistance caused by the RF induction coil 30 being too long, but also possible to avoid prolonging the cleaning time due to standing wave effect caused by the RF induction coil 30 being too long.

[0082] Specifically, Figure 1 Assume that the radio frequency of the radio frequency signal in the semiconductor cleaning device 100a shown in the figure and the semiconductor cleaning device 100 of the present embodiment is 2 MHz, and the diameters of the radio frequency induction coils 30 of the two are the same, and the wavelength of the radio frequency signal is 150 m. Figure 1The length l of the RF induction coil 30a in the semiconductor cleaning equipment 100a shown is 1 / 3 of the wavelength of the RF signal, that is, l=50m. At this time, the RF induction coil 30a can surround the entire graphite boat 200. The length L of the RF induction coil 30 in the semiconductor cleaning equipment 100 of this embodiment is 1 / 12 of the wavelength of the RF signal, that is, L=l*1 / 4=12.5m.

[0083] according to Figure 1 In the semiconductor cleaning device 100a provided in the related art, the theoretical current value of the RF induction coil 30a is I1, P=I1 2 R1, R1 = ρl / S, where ρ is the resistivity and S is the cross-sectional area of ​​the RF induction coil 30a. If the electromagnetic field is ideally uniform, the theoretical time required to clean the entire graphite boat 200 using the semiconductor cleaning equipment 100a is T'. However, due to the standing wave effect on the RF induction coil 30a, the uniformity of the electromagnetic field generated by the RF induction coil 30a is approximately 20%, and the electromagnetic field uniformity is not good. Therefore, the current at some positions on the RF induction coil 30a is only 80% of the theoretical current value. At this time, in order to ensure that all parts of the graphite boat 200 can meet the cleaning requirements, the cleaning time needs to be doubled. The actual time required to clean the entire graphite boat 200 using the semiconductor cleaning equipment 100a is T z 'is 2T'.

[0084] according to Figure 2 In the semiconductor cleaning device 100 provided in this embodiment, the theoretical current value of the RF induction coil 30 is I2, P=I2 2 R2, R2 = ρL / S. Figure 1 The semiconductor cleaning equipment 100a and Figure 2 The diameters of the RF induction coils 30 in the semiconductor cleaning equipment 100 shown are the same, so the cross-sectional areas of the RF induction coils 30 used in the two are the same. Therefore, it can be concluded that R2 = R1*1 / 4, and I2 = 2*I1. Thus, the density of the plasma generated by the RF induction coils 30 in this embodiment is approximately Figure 1 The density of the plasma excited by the medium RF induction coil 30a is 10 times that of the plasma excited by the medium RF induction coil 30a. Accordingly, when the semiconductor cleaning device 100 is used for cleaning, the time required to clean any boat section is T s is one tenth of T', T s =T'*1 / 10. In addition, the length L of the RF induction coil 30 in the semiconductor cleaning device 100 of the present embodiment is 1 / 12 of the wavelength of the RF signal, and the uniformity of the electromagnetic field generated by the RF induction coil 30 is about 3%. The electromagnetic field has good uniformity and a good cleaning effect. Cleaning any boat section once can meet the cleaning requirements, so there is no need to extend the cleaning time.

[0085] It should be noted that since L = l*1 / 4, Figure 2 When the semiconductor cleaning device 100 shown in the figure is cleaning, the RF induction coil 30 can surround a quarter of the graphite boat 200, so the number of boat sections can be regarded as 4. The RF induction coil 30 moves along the first direction X to sequentially clean the first boat section, the second boat section, the third boat section and the fourth boat section. Therefore, the semiconductor cleaning device 100 takes a time T to clean the entire graphite boat 200. z =4*T s =T'*4 / 10.

[0086] In general, the use of Figure 2 The semiconductor cleaning device 100 shown in the figure takes a long time T to clean the entire graphite boat 200. z is to use Figure 1 The time required for the semiconductor cleaning equipment 100a to clean the graphite boat 200 is T z It can be seen that the semiconductor cleaning equipment 100 of this embodiment can effectively solve the problem of long cleaning time of the graphite boat 200.

[0087] As a further optional embodiment, the length of the RF induction coil 30 may be less than one tenth of the wavelength of the RF signal. By further shortening the length of the RF induction coil 30, the possibility of the RF induction coil 30 generating a standing wave effect can be further reduced, thereby ensuring the uniformity of the electromagnetic field and improving the cleaning quality without extending the cleaning time.

[0088] Exemplarily, the RF frequency of the RF signal is 2 MHz, and correspondingly, when the wavelength of the RF signal is 150 m, the length L of the RF induction coil 30 needs to be less than 15 m. In this embodiment, if the diameter of the RF induction coil 30 is 0.6 m, according to L=πdn, the number of turns n of the RF induction coil 30 is ≤7.9, and the number of turns n of the RF induction coil 30 can be, for example, 4, 5, 6, or 7.

[0089] Figure 5 This is a schematic diagram of the coordination of the fixed support 50, the RF induction coil 30 and the process tube 20 in a semiconductor cleaning device 100 provided in an embodiment of the present application. Figure 5 There is a gap between the RF induction coil 30 and the outer surface of the process tube 20. Thus, the RF induction coil 30 does not contact the outer surface of the process tube 20, ensuring that the RF induction coil 30 can move smoothly along the first direction X without friction with the process tube 20 during movement.

[0090] In a specific example, the dimension Δd of the gap along the radial direction of the process tube 20 is greater than or equal to 10 mm and less than or equal to 50 mm. In other words, one turn of the wire of the RF induction coil 30 is concentrically arranged with the process tube 20, and the diameter D1 of the circle surrounded by one turn of the wire of the RF induction coil 30 is greater than the diameter D2 of the process tube 20, and 10 mm ≤ Δd = 1 / 2 (D1-D2) ≤ 50 mm.

[0091] If the size Δd of the gap is less than 10 mm, the RF induction coil 30 is too close to the outer surface of the process tube 20, which may affect the movement of the RF induction coil 30; if the size Δd of the gap is greater than 50 mm, the RF induction coil 30 is too far from the outer surface of the process tube 20, and the magnetic field strength of the electromagnetic field generated by the RF induction coil 30 in the cavity is relatively small, which affects the dissociation effect on the process gas. In this embodiment, by designing 10 mm ≤ Δd ≤ 50 mm, it is ensured that the RF induction coil 30 can move smoothly and that the magnetic field strength of the electromagnetic field generated by the RF induction coil 30 in the cavity is relatively large.

[0092] In the embodiment where there is a gap between the RF induction coil 30 and the outer surface of the process tube 20, it should be noted that the RF induction coil 30 should be made of a rigid material to prevent the parts of the turns of the RF induction coil 30 that are not fixed to the fixing bracket 50 from deforming and contacting the outer surface of the process tube 20. Exemplarily, the material of the RF induction coil 30 can be conductive materials such as copper and silver. Compared with materials such as brass, copper has better conductivity, so that the RF induction coil 30 made of copper has good conductivity.

[0093] Please continue to refer to Figure 5 The fixed bracket 50 includes a metal mounting plate 51 and an insulating plate 52. The metal mounting plate 51 is connected to the frame 10 and can move relative to the frame 10 along the first direction X. The insulating plate 52 is fixedly connected to the metal mounting plate 51. Each turn of the wire of the RF induction coil 30 is fixed on a surface of the insulating plate 52 facing the process pipe 20 to insulate the RF induction coil 30 from the metal mounting plate 51.

[0094] The metal mounting plate 51 can be made of aluminum (Al) or copper. The insulating plate 52 can be made of insulating materials such as ceramics, plastics or rubber.

[0095] By combining a metal mounting plate 51 and an insulating plate 52 to form a fixing bracket 50, the fixing bracket 50 has a high structural strength so as to stably fix the RF induction coil 30; at the same time, each turn of the RF induction coil 30 is fixed on the insulating plate 52 to avoid short circuit caused by the conduction of each turn of the RF induction coil 30.

[0096] In some embodiments, please refer to Figure 2 and Figure 5 , there can be two fixing brackets 50, the two fixing brackets 50 are arranged opposite to each other, and the process pipe 20 is located between the two fixing brackets 50. By increasing the number of fixing brackets 50, the number of fixing points of the RF induction coil 30 on the fixing brackets 50 is increased, thereby improving the installation reliability of the RF induction coil 30. Figure 2 In the example shown, the metal mounting plates 51 of the two fixing brackets 50 are arranged along the second direction ( Figure 2 The two ends of the mounting plate 50 are connected to the frame 10 respectively, and the two fixing brackets 50 are arranged opposite to each other and spaced apart along the third direction, wherein the third direction is in the thickness direction of the metal mounting plate 51 ( Figure 2 In the figure, the two fixing brackets 50 are parallel to each other, and at this time, the two fixing brackets 50 are located on both sides of the process pipe 20 along the third direction Z.

[0097] Of course, in other embodiments, two fixing brackets 50 may also be disposed on both sides of the process tube 20 along the Y direction, and the metal mounting plates 51 of each fixing bracket 50 are connected to the frame 10 at both ends along the Z direction.

[0098] The following description will be made by taking the case where two fixed brackets 50 are provided and the two fixed brackets 50 are arranged relatively to each other along the Z direction as an example. After reading the following description, those skilled in the art can obviously understand the technical solution of the two fixed brackets 50 being arranged relatively to each other along the Y direction, or the technical solution of the four fixed brackets 50 being provided, two of which are arranged relatively to each other along the Y direction, and the other two being arranged relatively to each other along the Z direction.

[0099] In some embodiments of the present application, four slideways are provided on the rack 10, and the slideways extend along the first direction X. In this embodiment, sliders 55 are correspondingly provided at both ends of each metal mounting plate 51 along the second direction, and each slider 55 is correspondingly slidably matched with a slideway.

[0100] The slideway can be specifically a slide groove formed on the frame 10, and the slide groove can be made by machining. Alternatively, in an alternative embodiment, a guide rail 70 can be fixedly mounted on the frame 10, and the slideway at this time is the track of the guide rail 70, wherein the guide rail 70 can be obtained by purchasing.

[0101] By providing the slideway and the slider 55, the sliding cooperation relationship between the slider 55 and the slideway can play a guiding role, so as to guide the fixed bracket 50 to drive the RF induction coil 30 to move along the first direction X. It should be noted that in this embodiment, the driving device can be connected to one of the multiple fixed brackets 50 in a transmission manner, and the driving device drives one fixed bracket 50 to move, and the sliders 55 on the other fixed brackets 50 can slide on the corresponding slideway accordingly. At this time, there are multiple fixed brackets 50 driving the RF induction coil 30 to move, which further ensures that the RF induction coil 30 can move smoothly and steadily.

[0102] Please continue to refer to Figures 3 to 5 The semiconductor cleaning equipment 100 further includes a first connector 42 and a second connector 43 mounted on the fixing bracket 50, wherein the first connector 42 is connected to the input terminal, and the second connector 43 is connected to the ground terminal, and the first connector 42 and the second connector 43 are respectively electrically connected to the RF power supply 40 through the flexible cable 41. Specifically, one end of the metal mounting plate 51 protrudes toward the process tube 20 to form a flange 511, and the first connector 42 and the second connector 43 can be mounted on the flange 511.

[0103] Thus, the RF power source 40 loads RF power to the RF induction coil 30 through an intermediate medium (i.e., the first connector 42 and the second connector 43). And by designing that the first connector 42 and the second connector 43 are installed on the fixed bracket 50, the first connector 42 and the second connector 43 can be conveniently moved with the fixed bracket 50 to change positions, ensuring that the RF induction coil 30 can move smoothly to achieve segmented cleaning. In addition, the connector and the RF power source 40 are connected by a flexible cable 41. When the driving device drives the fixed bracket 50 to move, the flexible cable 41 can be stretched and deformed to ensure that the RF induction coil 30 can move smoothly.

[0104] The first connector 42 and the second connector 43 may be any one of an N-type RF connector, an NH-type RF connector, and an LC RF connector.

[0105] The connection between the first connector 42 and the input terminal, and between the second connector 43 and the ground terminal can be achieved by clamping, welding, screwing or other connection techniques in the art. Taking screwing as an example, the input terminal can be fixed to the first connector 42 by screws.

[0106] In an embodiment in which two fixing brackets 50 are provided, the two fixing brackets 50 are arranged opposite to each other along the third direction Z. Figure 5 As shown, the first connector 42 and the second connector 43 can be arranged on the same fixed bracket 50. In this way, the input end and the ground end of the RF induction coil 30 are wound to the same side of the process tube 20 to avoid the existence of redundant parts of the RF induction coil 30 and to avoid the contact of the wire with the outer surface of the process tube 20 as much as possible. In this example, the RF power supply 40 can be arranged close to the fixed bracket 50 on which the connector is fixed, and the RF power supply 40 can be conveniently connected to the first connector 42 and the second connector 43 through the flexible cable 41, so that the flexible cable 41 is as short as possible under the premise that the RF induction coil 30 can move smoothly, so as to avoid the redundant part of the flexible cable 41 being too long.

[0107] The specific structure of each turn of the wire of the radio frequency induction coil 30 being fixed on the insulating plate 52 will be described in detail below with reference to the accompanying drawings.

[0108] Figure 6 This is a partial schematic diagram of the cooperation between the fixing bracket 50 and the radio frequency induction coil 30 in a semiconductor cleaning device 100 provided in an embodiment of the present application. Figure 6 A plurality of limiting spaces are formed on one surface of the insulating plate 52 facing the process tube 20, and each turn of the wire of the RF induction coil 30 is correspondingly inserted into a limiting space, so that the displacement of each turn of the wire along the thickness direction Z of the insulating plate 52 is limited to prevent the wire from being deformed under the action of gravity and fitting with the outer surface of the process tube 20, so as to ensure that the RF induction coil 30 can move smoothly.

[0109] In a possible manner, the insulating plate 52 may be protrudingly disposed on the metal mounting plate 51. In other words, compared with the side of the metal mounting plate 51 facing the process tube 20, the side of the insulating plate 52 facing the process tube 20 is closer to the process tube 20. Based on this embodiment, a plurality of slots are formed on the side of the insulating plate 52 facing the process tube 20, and the slots extend along the second direction and penetrate the top and bottom surfaces of the insulating plate 52. The plurality of slots are sequentially arranged at intervals along the first direction, and the slots are limit spaces, and each turn of the wire can be clamped in a slot accordingly.

[0110] In another possible embodiment, the metal mounting plate 51 is recessed in a direction away from the process tube 20 to form a groove, the insulating plate 52 is located in the groove, and the thickness of the insulating plate 52 is equal to the depth of the groove. That is, the side of the insulating plate 52 facing the process tube 20 is coplanar and flush with the side of the metal mounting plate 51 facing the process tube 20, and the insulating plate 52 does not protrude from the side of the metal mounting plate 51 facing the process tube 20. Compared with the embodiment in which the insulating plate 52 protrudes from the side of the metal mounting plate 51 facing the process tube 20, the present embodiment is designed in such a way that the insulating plate 52 does not occupy the space between the side of the metal mounting plate 51 facing the process tube 20 and the process tube 20. If the distance between the two metal mounting plates 51 along the third direction Y in the two possible embodiments is the same, then the gap between the RF induction coil 30 and the outer surface of the process tube 20 in the present embodiment can be larger to reduce the possibility of the RF induction coil 30 contacting the outer surface of the process tube 20.

[0111] Based on this embodiment, Figure 6As shown, the fixing bracket 50 may also include a plurality of limiting plates 53, each limiting plate 53 is connected to a connecting plate 54 at both ends along the first direction, the connecting plate 54 is fixedly connected to a side of the insulating plate 52 facing the process tube 20, and the limiting plate 53 and the side of the insulating plate 52 facing the process tube 20 together enclose a limiting space. In this embodiment, an exemplary process of fixing the wire to the insulating plate 52 is: fit the wire to a suitable position of a side of the insulating plate 52 facing the process tube 20; fit the connecting plates 54 at both ends of a limiting plate 53 to the insulating plate 52, and make the two connecting plates 54 located on both sides of the wire along the first direction; and connect the two connecting plates 54 to the insulating plate 52.

[0112] In some embodiments, the limiting plate 53 may also be configured such that one end is connected to the insulating plate 52 through the connecting plate 54, the limiting plate 53 is elastic, and the other end of the limiting plate 53 is a free end. In this embodiment, an exemplary process of fixing the wire to the insulating plate 52 is as follows: pull the other end of the limiting plate 53 so that the other end of the limiting plate 53 is away from the insulating plate 52 to form a gap with the side of the insulating plate 52 facing the process tube 20; pass the wire through the gap into the limiting space surrounded by the limiting plate 53 and the insulating plate 52; loosen the other end of the limiting plate 53, the limiting plate 53 restores its deformation, the other end of the limiting plate 53 abuts against the side of the insulating plate 52 facing the process tube 20, and the wire is clamped in the limiting space.

[0113] The above-mentioned limit plate 53 is not limited to Figure 6 In the flat plate structure shown, in some feasible implementations, the limiting plate 53 may also be an arc-shaped plate, etc., and the arc-shaped plate surrounds the outside of the wire.

[0114] As disclosed herein, the connecting plate 54 and the insulating plate 52 can be connected by means of clamping, welding, bonding or screwing. Similarly, the connection technology such as clamping, welding, bonding or screwing can also be used to realize the connection between the insulating plate 52 and the mounting plate. Taking screwing as an example, screws can be used to connect the connecting plate 54 and the insulating plate 52, and the insulating plate 52 and the mounting plate. Optionally, the screws can be made of insulating materials such as ceramics and plastics to avoid short circuits caused by the conduction of two turns of wire through the screws and the metal mounting plate 51. Of course, in some embodiments of the present application, the screws can also be made of metal materials to be metal screws. In this example, in order to avoid short circuits caused by the conduction of two turns of wire through the screws and the metal mounting plate 51, the distance between any screw and the wire along the first direction X should be greater than 50 mm.

[0115] In other embodiments, a plurality of groups of limiting components may be protruded from one side of the insulating plate 52 facing the process tube 20, and each group of limiting components includes a first protrusion and a second protrusion arranged relatively to each other along the first direction X, so that the first protrusion, the second protrusion and the insulating plate 52 together form a limiting space for clamping the wire, and the wire is clamped between the first protrusion and the second protrusion.

[0116] The specific implementation of the driving device will be described in detail below with reference to the accompanying drawings. Figure 7 for Figure 2 The enlarged view of the part A in the semiconductor cleaning equipment 100 is shown. Figure 8 for Figure 2 The enlarged view of the part B in the semiconductor cleaning equipment 100 is shown. Figure 2 and Figure 7 The driving device includes a driving motor 60 and a transmission device. The driving motor 60 is arranged on the frame 10. The transmission device is used to convert the rotational power of the driving motor 60 into linear power and transmit it to the metal mounting plate 51 to drive the metal mounting plate 51 to move along the first direction.

[0117] Exemplarily, the transmission device includes a synchronous shaft, a driving pulley 63, a driven pulley and a conveyor belt 61, the rotation axis of the synchronous shaft extends along the third direction Z, one end of the synchronous shaft is connected to the motor shaft of the drive motor 60, the driving pulley 63 is sleeved on the other end of the synchronous shaft, the driven pulley is rotatably connected to the frame 10, the rotation axis of the driven pulley is parallel to the rotation axis of the synchronous shaft, and the conveyor belt 61 spans between the driving pulley 63 and the driven pulley. In addition, a transmission member 611 is fixedly provided on the conveyor belt 61, and the transmission member 611 is fixedly connected to the metal mounting plate 51. Specifically, the transmission device may include a rotating shaft, which extends along the third direction Z, one end of which is rotatably connected to the frame 10, and the driven pulley is sleeved on the other end of the rotating shaft.

[0118] In this way, the driving motor 60 runs, the motor shaft rotates, the synchronous shaft rotates around the rotation axis, the driving pulley 63 also rotates, and then drives the conveyor belt 61 and the transmission member 611 to move along the first direction X, and the metal mounting plate 51 connected to the transmission member 611 drives the RF induction coil 30 to move.

[0119] It is understood that the transmission member 611 is fixedly connected to the metal mounting plate 51 in a broad sense. For example, it can be understood that the transmission member 611 is directly connected to the metal mounting plate 51, or it can be understood that the transmission member 611 is indirectly connected to the metal mounting plate 51. Figure 8 In the specific example shown, in an embodiment where sliders 55 are provided at both ends of the metal mounting plate 51 along the second direction, the transmission member 611 may be a plate-shaped structure, and the transmission member 611 may be connected to the sliders 55. Thus, when the transmission member 611 moves, the sliders 55 move accordingly, thereby driving the metal mounting plate 51 connected thereto to move.

[0120] The transmission member 611 can be screwed to the conveyor belt 61 by screws, or the transmission member 611 can be connected to the conveyor belt 61 by other connection methods such as welding. Figure 8In the embodiment where the transmission member 611 and the conveyor belt 61 are screwed together, the transmission device may further include a pressing plate 612, the pressing plate 612 is directly opposite to the transmission member 611, the pressing plate 612 and the transmission member 611 jointly clamp a portion of the conveyor belt 61, and the screws sequentially penetrate the pressing plate 612 and the conveyor belt 61, and then extend into the interior of the transmission member 611 and are screwed together with the transmission member 611. In this way, the pressing plate 612 provides an installation position for the installation of the screws.

[0121] Moreover, since the length of the graphite boat 200 is relatively large, generally up to 1.5 m, the length of the process tube 20 along the first direction is generally greater than 1.5 m, and the size of the semiconductor cleaning equipment 100 along the first direction is large. In this embodiment, the transmission device is a belt transmission mechanism. Compared with the transmission device being a gear rack mechanism, the belt transmission mechanism has the advantage of a transmission with a larger center distance between the two shafts, so that the transmission device can be applied to the semiconductor cleaning equipment 100 to achieve smooth transmission.

[0122] Please continue to refer to Figure 7 The semiconductor cleaning equipment 100 further includes a connecting support 66, a motor support 65 and a supporting support 64. The connecting support 66 is in a “┐” shape. The connecting support 66 is fixedly connected to the frame 10. One end of the supporting support 64 is connected to the connecting support 66 and the other end is connected to the motor support 65. The driving motor 60 is fixedly arranged on the motor support 65. By such an arrangement, the frame 10 provides support for the connecting support 66, the motor support 65 and the supporting support 64, and the motor support 65 provides support for the driving motor 60.

[0123] In this embodiment, the support bracket 64 is provided with a first through hole and a second through hole, the central axes of the first through hole and the second through hole are colinear and extend along the third direction Z, the synchronization shaft is passed through the first through hole and the second through hole, and the other end of the synchronization shaft is connected to the driving pulley 63 after passing through the second through hole. Among them, a bearing is sleeved between the synchronization shaft and the hole wall of the first through hole and the second through hole, so that the support bracket 64 can support the synchronization shaft and ensure that the synchronization shaft can rotate, so as to ensure that the transmission device can achieve transmission.

[0124] Please continue to refer to Figure 2 The frame 10 includes a main frame 11 and a partition frame 12. The main frame 11 is a rectangular frame structure, and the partition frame 12 is a rectangular frame structure. The partition frame 12 is arranged in the main frame 11 to separate the main frame 11 into a first space and a second space. The process pipe 20 is located in the first space, and the connecting support 66, the motor support 65 and the support support 64 are all located in the second space.

[0125] Through such an arrangement, the process pipe 20 is installed in the first space, and the drive motor 60, the transmission device and other components are installed in the second space, and sufficient installation space is reserved for the drive motor 60, the transmission device, the connecting support 66, the motor support 65 and the support support 64, which is beneficial to avoid interference between these components and the process pipe 20 during the installation process.

[0126] Fig. 9 A schematic diagram of a cleaning method provided in an embodiment of the present application. Fig. 9 The present application also provides a cleaning method, which is applied to the semiconductor cleaning device 100 described in the above embodiments of the present invention to clean the graphite boat 200. The cleaning method specifically includes the following steps:

[0127] S10, placing a graphite boat to be cleaned into a cavity of a process tube; wherein the graphite boat has a plurality of boat sections sequentially arranged along a first direction.

[0128] As can be seen from the foregoing, the number of boat segments is related to the number of turns n of the RF induction coil 30 and the length of the RF induction coil 30. When the RF induction coil 30 can surround one-third of the circumference of the graphite boat, the number of boat segments is three, which will not be listed one by one in this embodiment.

[0129] S20, boat cleaning step, controlling the driving device to drive the fixed bracket to move along the first direction relative to the process tube, so as to drive the RF induction coil to move along the first direction to the periphery surrounding one of the boat segments, loading RF power to the RF induction coil, so that the process gas in the cavity forms plasma, and maintaining the position of the RF induction coil within a preset time, so that the boat segment is cleaned.

[0130] In this step, the RF induction coil is maintained at the corresponding position for a preset time period, and the RF induction coil is also loaded with RF power during the preset time period, so that plasma is generated in a partial area of ​​the cavity surrounded by the RF induction coil.

[0131] Here, the timing is specifically performed by a timer to determine whether the preset time has been reached. For example, the specific process of S20 may be: i) controlling the driving device to drive the fixed support to move relative to the process tube in the first direction, so as to drive the RF induction coil to move in the first direction to the periphery around one of the boat segments; ii) stopping driving the fixed support to maintain the position of the RF induction coil, and starting timing; iii) loading RF power to the RF induction coil so that the process gas in the cavity forms plasma; iv) when the timing time reaches the preset time, the boat segment is cleaned.

[0132] S30, returning to the boat segment cleaning step to clean another boat segment until all boat segments are cleaned.

[0133] When the semiconductor cleaning device 100 adopts the cleaning method, the length of the RF induction coil 30 is relatively small, and the RF induction coil 30 is driven to move by the driving device to achieve segmented cleaning of the graphite boat 200. In this way, the resistance R on the RF induction coil 30 is low and the current I is high, and the concentration of the plasma excited by the electromagnetic field generated by the RF induction coil 30 is higher, which can effectively avoid the extension of the cleaning time caused by the high resistance value caused by the excessive length of the RF induction coil 30, thereby facilitating the shortening of the cleaning time.

[0134] In some embodiments, between steps S20 and S30, the cleaning method further includes S40.

[0135] S40, stopping loading radio frequency power to the radio frequency induction coil.

[0136] With such a design, after cleaning one of the boat segments, the RF induction coil stops loading RF power to the RF induction coil when it moves to surround the other boat segment, and then loads RF power to the RF induction coil again when the RF induction coil moves to surround the other boat segment.

[0137] In this way, on the one hand, it is beneficial to save energy consumption, and on the other hand, it is beneficial to avoid exciting the process gas in the cavity to form plasma during the movement of the RF induction coil, that is, to avoid cleaning the graphite boat during the movement of the RF induction coil, so that the starting node of cleaning each boat segment is as far as possible after the boat segment is surrounded by the RF induction coil, so that the time required for cleaning each boat segment is more accurate.

[0138] It can be understood that in step S30, the order of cleaning the boat segments is not limited.

[0139] In one example, the RF induction coil 30 is initially wrapped around the outer circumference of a boat segment closest to the furnace opening of the process tube 20. Based on this, the order of cleaning each boat segment in step S30 is specifically to clean each boat segment in sequence from the furnace opening of the process tube 20 to the furnace tail of the process tube 20.

[0140] Specifically, in an embodiment in which the number of boat segments N is 3, and the three boat segments from the furnace mouth to the furnace tail of the process tube 20 are respectively called the first boat segment, the second boat segment, and the third boat segment, the cleaning order of each boat segment is: first clean the first boat segment, then clean the second boat segment, and finally clean the third boat segment.

[0141] It can be understood that a specific implementation process of the cleaning method may include the following steps.

[0142] Step 1: Place the graphite boat to be cleaned into the cavity of the process tube.

[0143] Step 2, controlling the driving device to drive the fixed bracket to move relative to the process tube along the first direction, so as to drive the RF induction coil to move along the first direction, so that the center of the RF induction coil moves to 1 / 6 of the length of the graphite boat, and the RF induction coil surrounds the first boat section; loading RF power to the RF induction coil so that the process gas in the cavity forms plasma, and maintaining the position of the RF induction coil within a preset time, so that the first boat section is cleaned.

[0144] Step 3: stop loading RF power to the RF induction coil.

[0145] Step 4, controlling the driving device to drive the fixed bracket to move relative to the process tube along the first direction, so as to drive the RF induction coil to move along the first direction, so that the center of the RF induction coil moves to 1 / 2 of the length of the graphite boat, and the RF induction coil surrounds the second boat section; loading RF power to the RF induction coil so that the process gas in the cavity forms plasma, and maintaining the position of the RF induction coil within a preset time, so that the second boat section is cleaned.

[0146] Step 5: stop loading RF power to the RF induction coil.

[0147] Step 6, controlling the driving device to drive the fixed bracket to move relative to the process tube along the first direction, so as to drive the RF induction coil to move along the first direction, so that the center of the RF induction coil moves to 5 / 6 of the length of the graphite boat, and the RF induction coil surrounds the third boat section; loading RF power to the RF induction coil so that the process gas in the cavity forms plasma, and maintaining the position of the RF induction coil within a preset time, so that the third boat section is cleaned.

[0148] In another example, the RF induction coil 30 is initially surrounded by the outer circumference of a boat segment closest to the furnace tail of the process tube 20. Based on this, the order of cleaning each boat segment in step S30 is specifically to clean each boat segment in sequence from the furnace tail of the process tube 20 to the furnace mouth of the process tube 20.

[0149] Specifically, in an embodiment in which the number of boat segments N is 3, and the three boat segments from the furnace mouth to the furnace tail of the process tube 20 are respectively called the first boat segment, the second boat segment, and the third boat segment, the cleaning order of each boat segment is: first clean the third boat segment, then clean the second boat segment, and finally clean the first boat segment.

[0150] By adopting this cleaning method, on the basis of ensuring that each boat segment can be cleaned, the moving direction of the RF induction coil 30 does not need to be changed, which is conducive to avoiding the RF induction coil 30 moving back and forth along the first direction, which causes the cleaning time to be extended, ensuring that the cleaning time is as short as possible, and improving the cleaning efficiency.

[0151] It is to be understood that the above embodiments are merely exemplary embodiments used to illustrate the principles of the present invention, but the present invention is not limited thereto. For those of ordinary skill in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims

1. A semiconductor cleaning device, characterized in that: include: frame; A process tube having a cavity therein, wherein the cavity is used to accommodate the graphite boat to be cleaned; A fixed bracket connected to the frame and movable relative to the frame; A radio frequency induction coil is wound around the outer circumference of the process tube, each turn of the wire of the radio frequency induction coil is fixed on the fixed bracket, and the radio frequency induction coil is used to make the process gas in the process tube form plasma; A driving device is used to drive the fixed support to move along a first direction, so as to drive the radio frequency induction coil to move along the first direction relative to the process tube; wherein the first direction is parallel to the length direction of the process tube.

2. The semiconductor cleaning equipment according to claim 1, characterized in that: The length of the radio frequency induction coil is less than a quarter of the wavelength of the radio frequency signal applied to the radio frequency induction coil.

3. The semiconductor cleaning equipment according to claim 2, characterized in that: The length of the radio frequency induction coil is less than one tenth of the wavelength of the radio frequency signal.

4. The semiconductor cleaning equipment according to claim 1, characterized in that: It also includes a radio frequency power supply arranged outside the process tube, and the radio frequency power supply is used to output a radio frequency signal; The two ends of the RF induction coil are respectively an input end and a ground end; the semiconductor cleaning equipment also includes a first connector and a second connector installed on the fixed bracket, the first connector is connected to the input end, the second connector is connected to the ground end, and the first connector and the second connector are respectively electrically connected to the RF power supply through flexible cables.

5. The semiconductor cleaning equipment according to claim 4, characterized in that: There are two fixed brackets, the two fixed brackets are arranged opposite to each other, and the process pipe is located between the two fixed brackets; The first connector and the second connector are arranged on the same fixing bracket.

6. The semiconductor cleaning equipment according to claim 1, characterized in that: There is a gap between the radio frequency induction coil and the outer surface of the process tube.

7. The semiconductor cleaning equipment according to claim 6, characterized in that: The dimension of the gap along the radial direction of the process pipe is greater than or equal to 10 mm and less than or equal to 50 mm.

8. The semiconductor cleaning equipment according to any one of claims 1 to 7, characterized in that: The fixed bracket includes a metal mounting plate and an insulating plate, the insulating plate is fixedly connected to the metal mounting plate, and each turn of the wire of the radio frequency induction coil is fixed on a surface of the insulating plate facing the process pipe to insulate and isolate the radio frequency induction coil from the metal mounting plate.

9. The semiconductor cleaning equipment according to claim 8, characterized in that: A plurality of limiting spaces are formed on a surface of the insulating plate facing the process tube, and each turn of the wire of the radio frequency induction coil is correspondingly inserted into one of the limiting spaces, so that the displacement of each turn of the wire along the thickness direction of the insulating plate is limited.

10. The semiconductor cleaning equipment according to claim 9, characterized in that: The metal mounting plate is recessed in a direction away from the process tube to form a groove, the insulating plate is located in the groove, and the thickness of the insulating plate is equal to the depth of the groove; and / or, The fixing bracket further includes a plurality of limiting plates, at least one end of which along the first direction is fixedly connected to a surface of the insulating plate facing the process tube, and the limiting plate and the insulating plate together enclose a limiting space.

11. The semiconductor cleaning equipment according to claim 8, characterized in that: The frame is provided with a plurality of slides, and the slides extend along the first direction; sliders are provided at both ends of the metal mounting plate along the second direction, and each slider slides with one of the slides; wherein the second direction is perpendicular to the first direction and the thickness direction of the metal mounting plate.

12. The semiconductor cleaning equipment according to claim 8, characterized in that: The driving device comprises a driving motor and a transmission device. The driving motor is arranged on the frame, and the transmission device is used to convert the rotational power of the driving motor into linear power and transmit it to the metal mounting plate to drive the metal mounting plate to move along the first direction.

13. A cleaning method, characterized in that: Applied to the semiconductor cleaning equipment according to any one of claims 1 to 12, the cleaning method comprises: Placing a graphite boat to be cleaned into a cavity of a process tube; wherein the graphite boat has a plurality of boat sections sequentially arranged along a first direction; a boat cleaning step, controlling the driving device to drive the fixed support to move relative to the process tube in a first direction, so as to drive the RF induction coil to move along the first direction to the periphery surrounding one of the boat segments, applying RF power to the RF induction coil so that the process gas in the chamber forms plasma, and maintaining the position of the RF induction coil within a preset time, so that the boat segment is cleaned; Return to the boat segment cleaning step to clean another boat segment until all the boat segments have been cleaned.

14. The cleaning method according to claim 13, characterized in that: The RF induction coil is initially surrounded by the outer periphery of a boat segment close to the furnace opening of the process tube; when all the boat segments are cleaned, the boat segments are cleaned sequentially from the furnace opening of the process tube to the furnace end of the process tube; or, The RF induction coil is initially surrounded by the outer periphery of a boat segment close to the furnace tail of the process tube; when all the boat segments are cleaned, each boat segment is cleaned sequentially from the furnace tail of the process tube to the furnace mouth of the process tube.

15. The cleaning method according to claim 13, characterized in that: After the boat cleaning step and before returning to the boat cleaning step, the cleaning method further comprises: Stop applying radio frequency power to the radio frequency induction coil.

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