Thin film deposition apparatus

Abstract

The present invention provides a thin film deposition apparatus comprising: a processing cavity for depositing thin films; a gas supply assembly provided on the top wall of the processing cavity for supplying process gas into the processing cavity; a heating tray provided below the gas supply assembly for supporting and heating the substrate; an upper electrode and a lower electrode for forming a uniform electric field within the processing cavity; and a radio frequency source connected to the upper electrode and the lower electrode for supplying radio frequency power, exciting the process gas inside the processing cavity to dissociate it into plasma gas, and allowing the plasma gas to deposit a thin film on the substrate. The upper electrode and the lower electrode are the same size or have a difference of ±10 mm, and the diameter of the lower electrode is smaller than that of the substrate, so that a uniform electric field is generated between the upper electrode and the lower electrode. The present invention can guarantee a uniform distribution of the electric field within the process cavity, resulting in good uniformity of the deposited thin film, and can particularly guarantee uniformity of the thin film even in continuous stacking of 300 layers or more to 1000 layers or more.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor manufacturing technology, and particularly to a thin film deposition apparatus.

Background Art

[0002] In the vacuum processing cavity of plasma enhanced chemical vapor deposition (PECVD), layer stack structures of different materials are deposited on a substrate. The substrate is set in the processing cavity, and first a first processing gas is passed through to form a first layer of a first material on the substrate. Plasma purification and gas purification are then performed, and then a second processing gas for forming a second layer of a second material on the substrate is circulated. The above-described plasma purification and gas purification are repeated to stack and deposit the first material and the second material on the substrate to form a thin film of a layer stack structure. Three-dimensional (3D) storage may be composed of a layer stack structure of alternating thin film materials deposited on a substrate. Currently, 3D storage achieves the purpose of data storage in a three-dimensional structure through related processes using alternating layers of oxides and nitride films. These stack structures can include a plurality of layers of a first material and a second material, for example, a continuous stack of 300 layers or more, or 1000 layers or more.

[0003] Specifically, the stack structure of the first material and the second material in the thin film material of the 3D storage stack may be oxides and silicon, silicon and doped silicon, or silicon and nitride. Therefore, many of the thin film materials of the 3D storage stack combining these materials can be applied to BiCS (Bit-Cost Scalable), TCAT (Terabit Cell Array Transistor) or other 3D storage structures. Also, the stack structure of the first material and the second material may be other material compositions, and the order in which the layers of the first material and the second material are deposited on the substrate may be reversed.

[0004] However, there is currently a problem with the non-uniformity of the thin films deposited in existing PECVD devices. As shown in Figure 1, the thin film thickness is uniform in the intermediate region of the substrate, but the thin film thickness in the 20-25 mm edge region tends to decrease before increasing. Figure 2 is a schematic diagram of the electric field distribution between the upper and lower electrodes of an existing PECVD device. This problem is mainly due to the uniform distribution of the electric field in the intermediate region of the substrate, as shown in the figure, resulting in uniform thin film thickness in the intermediate region. The diameter of the gas nozzle is about 350 mm, which is larger than the diameter of the substrate, so the electric field distribution between the gas nozzle and the substrate becomes non-uniform, forming a local gas concentration gradient at the substrate edge, causing gas deficiency regions near the substrate edge. Due to the electric field tension at the substrate edge, the thin film is thickest at the outermost edge and thinnest at the next edge during the deposition process. At the same time, existing PECVD equipment has too much particulate contaminant, resulting in excessively high cleaning frequency during the process.

[0005] Therefore, in order to solve the above problems, it is necessary to propose a new thin-film deposition apparatus. [Overview of the project]

[0006] This invention proposes a thin film deposition apparatus that can improve the uniformity of thin films. The thin-film deposition apparatus relating to this application is A processing cavity for thin film deposition, A gas supply assembly is provided on the top wall of the processing cavity for supplying process gas into the processing cavity, A heating tray is provided below the gas supply assembly for supporting and heating the substrate, Upper and lower electrodes for forming a uniform electric field within the processing cavity, The system comprises a radio frequency source connected to the upper and lower electrodes to supply radio frequency power, which excites the process gas inside the processing cavity and dissociates it into a plasma gas, causing the plasma gas to deposit a thin film on the substrate, The upper and lower electrodes are of the same size, or have a difference of ±10 mm, and the diameter of the lower electrode is smaller than that of the substrate, so that a uniform electric field is generated between the upper and lower electrodes.

[0007] The difference in diameter between the lower electrode and the substrate is 15 mm or less.

[0008] The upper electrode has the same diameter as the substrate or a difference of ±10 mm.

[0009] The rotation mechanism is for controlling the rotation of the heating tray relative to the substrate, or the heating tray together with the substrate, or the gas supply assembly relative to the substrate, or the support ring together with the substrate.

[0010] When the aforementioned rotating mechanism controls the rotation of the substrate, the gas supplied to the processing cavity is an inert gas.

[0011] The aforementioned inert gas is nitrogen gas.

[0012] The temperature of the inert gas introduced into the thin film deposition apparatus is 200 to 500°C.

[0013] The rotation mechanism turns on the radio frequency source when controlling the rotation of the substrate.

[0014] The thin-film deposition apparatus further includes a flow guide ring that surrounds the side wall of the upper electrode.

[0015] The diameter of the flow guide ring is greater than or equal to the diameter of the support ring.

[0016] The flow guide ring is an insulator.

[0017] The material of the flow guide ring is AlN or Al2O3.

[0018] The upper electrode is integrally configured with the gas supply device.

[0019] The gas supply assembly is an insulator, the upper electrode is located below the gas supply assembly, and the upper electrode is a mesh electrode.

[0020] The gas supply assembly is an insulator provided with a groove at the bottom, the air outlet of the gas supply assembly is located within the groove, and a mesh electrode is further embedded within the groove.

[0021] The groove is a circular groove.

[0022] The diameter of the circular groove is the same as that of the mesh electrode.

[0023] The present invention proposes a thin film deposition apparatus, a processing cavity for performing thin film deposition, a gas supply assembly provided on the top wall of the processing cavity for supplying a process gas into the processing cavity, a heating tray provided below the gas supply assembly for carrying and heating a substrate, a radio frequency source that supplies radio frequency power, excites the process gas inside the processing cavity to dissociate it into a plasma gas, and the plasma gas performs thin film deposition on the substrate, an insulating plate located below the gas supply assembly and having a plurality of vent holes opened therein for introducing the process gas into the processing cavity.

[0024] The thickness of the insulating plate is 0.2 mm or more.

[0025] The insulating plate is in contact with the bottom surface of the gas supply assembly.

[0026] The vent holes have the same diameter as the air outlet diameter.

[0027] The number of the vent holes is not less than the number of the air outlets.

[0028] Each air outlet in the gas supply assembly has a ventilation hole on the insulating plate corresponding to its position.

[0029] A gap is left between the insulating plate and the gas supply assembly, and an insulating ring is attached around the outside of the gap.

[0030] The insulating ring has an insulating plate edge that extends upward to the side wall enclosing the gas supply assembly.

[0031] The gap between the insulating plate and the gas supply assembly is 0.1 to 2 mm.

[0032] The insulating plate is made of a material that does not react with HF.

[0033] The insulating plate is made of sapphire or silicon carbide material.

[0034] The insulating board material contains quartz and silicon.

[0035] The aforementioned quartz is synthetic quartz mixed with silicon.

[0036] The aforementioned surface treatment of the insulating board involves roughening its surface.

[0037] The thin film deposition apparatus further comprises a support ring and a rotating mechanism, wherein the support ring is for supporting the substrate and the rotating mechanism is for controlling the rotation of the substrate.

[0038] The thin-film deposition apparatus provided by the present invention can guarantee a uniform distribution of the electric field within the process cavity, resulting in excellent uniformity of the deposited thin film, and can particularly guarantee uniformity of the thin film even with continuous stacking of 300 or more layers or 1000 or more layers. On the other hand, this apparatus can concentrate plasma energy on the substrate, and chemical reactions occur on or near the substrate, so reactions at the processing cavity walls can be reduced or eliminated. At the same time, since the guide ring and support ring are insulators, the amount of particulate matter generated is extremely small, which not only increases the service life of the entire cavity but also reduces cleaning time and frequency. [Brief explanation of the drawing]

[0039] Figure 1 is a schematic diagram of the thin film thickness distribution on a substrate after thin film deposition using an existing thin film deposition apparatus. Figure 2 shows the electric field distribution between the upper and lower electrodes of an existing thin-film deposition apparatus. Figure 3 is a cross-sectional view of a first embodiment of the thin-film deposition apparatus according to the present invention. Figure 4 is a cross-sectional view of a second embodiment of the thin-film deposition apparatus according to the present invention. Figure 5 is a cross-sectional view of a third embodiment of the thin-film deposition apparatus according to the present invention. Figure 6A is a schematic diagram of the air outlet of a thin-film deposition apparatus. Figure 6B is a schematic diagram of the mesh electrode in the second and third embodiments of the present invention. Figure 7A is a cross-sectional view of a fourth embodiment of the thin-film deposition apparatus according to the present invention. Figure 7B is a cross-sectional view of a fourth embodiment of the thin-film deposition apparatus according to the present invention. Figure 8 is a brush control diagram of the thin-film deposition apparatus according to the present invention. Figure 9A is a schematic diagram showing how a rotating mechanism controls the rotation of the gas nozzle. Figure 9B is a schematic diagram showing how the rotating mechanism controls the rotation of the heating tray. Figure 9C is a schematic diagram showing how a rotation mechanism controls the rotation of the support. [Modes for carrying out the invention]

[0040] Embodiments of the present invention will be described below by specific examples, but those skilled in the art will readily understand other advantages and effects of the present invention from the disclosure herein. The present invention can be carried out or applied by further different specific embodiments, and each detail herein can be modified or changed in various ways without departing from the spirit of the invention, based on different viewpoints and applications.

[0041] When a component is said to be "on another component," "connected to another component," "joined to another component," or "in contact with another component," it is understood that it may be directly on another component, connected to, joined to, or in contact with another component, or an intercalated component may exist. In contrast, when a component is said to be "directly on another component," "directly connected to," "directly joined to," or "in direct contact with" another component, no intercalated component exists.

[0042] Referring to Figures 1 to 9C, the illustrations provided in this embodiment schematically illustrate the basic concept of the present invention. The drawings show only the parts related to the present invention and are not based on the number, shape, and dimensions of the parts in actual implementation. The form, quantity, and ratio of each part in actual implementation can be arbitrarily changed, and the layout of the parts may also become more complex.

[0043] In the PECVD thin film deposition process, the uniformity of the thin film deteriorates due to the non-uniformity of the electric field distribution. When thin films of different materials are deposited alternately on a substrate, as the number of layers of the first and second materials alternately stacked on the substrate w increases, for example, beyond 300 layers or 1000 layers of continuous stacking, the thickness of the thin film in the layer stack structure formed on the substrate w increases, resulting in a phenomenon where the stacked thin film is uniform in the middle, thin at the edges, and thick at the outermost edges. In other words, as the number of layers in these layer stack structures increases, the uniformity of the thin film after stacking deteriorates, the uniformity of the thin film on the substrate w deviates from a controllable range, and it becomes impossible to achieve the accuracy of via etching in the subsequent etching process.

[0044] The present invention provides a specific embodiment of a thin film deposition apparatus to solve the above problems. Specifically, as shown in Figure 3, the thin film deposition apparatus comprises a processing cavity 1, a gas nozzle 2, a heating tray 3, a flow guide ring 5, and a radio frequency source 9. The processing cavity 1 is used to perform a thin film deposition process on a substrate w, the gas nozzle 2 is provided on the top wall of the processing cavity 1, and a plurality of air outlets 201 are opened in the gas nozzle 2 to form an air outlet region, which is used to supply process gas to the inside of the processing cavity 1 as shown in Figure 6A. The heating tray 3 is positioned below the gas nozzle 2 and is used to support and heat the substrate w, the radio frequency source 9 is used to supply radio frequency power and forms a radio frequency electric field inside the processing cavity 1, exciting the process gas inside the processing cavity 1 and dissociating it into plasma gas, and depositing a thin film on the substrate w with the dissociated plasma gas.

[0045] The apparatus further comprises an upper electrode and a lower electrode 12. In this embodiment, the gas nozzle 2 is the upper electrode, and a conventional spray-type flat electrode is employed. In order to form a uniform electric field and ensure the deposition of a thin film of uniform thickness, the sizes of the upper and lower electrodes are the same, or there is a difference of ±10 mm. In the context of this application, a difference of ±10 mm means that the difference in size between both the upper and lower electrodes is within 10 mm. On the other hand, the diameter of the lower electrode 12 is smaller than the diameter of the substrate w, and is 15 mm or less, so that a uniform high-frequency electric field is formed between the gas nozzle 2 and the substrate w, making the thin film deposited on the substrate w more uniform. Since the conventional gas nozzle is larger than the heating tray, the gas entering the processing cavity 1 is blocked from above by the gas nozzle 2 and discharged directly from the lower air outlets on both sides of the processing cavity 1. In this invention, since the upper and lower electrodes are the same size, after the gas enters the processing cavity 1, some of the process gas may advance upward and be discharged from the air outlet 201, resulting in an uneven and unstable airflow that may affect the uniformity of thin film deposition on the substrate. Therefore, it is preferable to add a flow guide ring 5 around the side of the gas outlet 2, and the material of the flow guide ring 5 is AlN or Al2O3.

[0046] This device further includes a support ring 4 and a rotational lifting mechanism 8 to make the thin film on the substrate w more uniform. The support ring 4 supports the substrate w and extends outward from the substrate w, and the support ring 4 is an insulator. When the support ring 4 is added, a flow guide ring 5 is also required. Without the flow guide ring 5, the support ring 4 protrudes beyond the upper gas outlet 2, preventing the gas from moving downward and exacerbating the situation where the gas moves upward. Preferably, the diameter of the flow guide ring 5 is greater than or equal to the diameter of the support ring 4.

[0047] The apparatus provided by the present invention further comprises a rotary lifting mechanism 8, which may have an integrated structure for rotation and lifting, or it may have separate rotating and lifting structures. The rotary lifting mechanism 8 can drive the support 4 or heating tray 3 to move up or down in the vertical direction to lift the substrate w from the heating tray 3 or place it on the heating tray 3. The rotating component of the rotary lifting mechanism 8 is used to control the rotation of the substrate w. As shown in Figure 9C, the rotation of the substrate w may be caused by the rotary lifting mechanism 8 driving the support ring 4, thereby rotating the substrate w; as shown in Figure 9B, the rotary lifting mechanism 8 may drive the heating tray 3 to rotate it relative to the substrate w, or the heating tray 3 and the substrate w may rotate together; and as shown in Figure 9A, the rotary lifting mechanism 8 may rotate the upper gas nozzle 2 relative to the substrate w. In the embodiment in which the heating tray 3 is rotated relative to the substrate w, the rotary lifting mechanism 8 must first lower the heating tray 3 to a certain height. The rotation axis AA' of this rotation is vertical and penetrates the substrate w. Also, as shown in Figure 8, the device is provided with three brushes 10, of which two brushes 10 are connected to the heating power supply of the heating tray 3, and one brush 10 is connected to the radio frequency power supply.

[0048] The apparatus further includes a controller, which is connected to the gas nozzle 2, the radio frequency source 9, the heating tray 3, and the rotary lifting mechanism 8, respectively, and controls the operation of the gas nozzle 2, the radio frequency source 9, the heating tray 3, and the rotary lifting mechanism 8. The controller is configured to build a program menu, which includes keeping the radio frequency source 9 ON while the substrate w is rotating. When the rotary lifting mechanism 8 rotates the substrate w, it stops the inflow of process gas into the processing cavity 1, allows an inert gas such as nitrogen gas or helium gas to pass through the processing cavity 1 to maintain the pressure inside the processing cavity 1, and keeps the radio frequency source 9 ON. After a certain number of thin films are deposited on the substrate w, some impurity particles are suspended inside the processing cavity 1. At this time, the radio frequency source 9 is kept ON, filling the processing cavity 1 with a radio frequency electric field. The impurity particles become charged by the action of the radio frequency electric field inside the processing cavity 1, and the charged impurity particles do not fall onto the surface of the substrate w. This effectively prevents impurity particles from falling onto the thin films deposited on the substrate w, thus avoiding contamination of the thin films deposited on the substrate w. Preferably, the internal temperature of the processing cavity 1 is 200 to 500°C, or the temperature of the gas passing through is 200 to 500°C, at which temperature the gas does not react or condense.

[0049] In this embodiment, the number of rotations of the substrate w after thin film deposition is 5, and the set angle of each rotation is 60 degrees; or the number of rotations of the substrate w is 3, and the set angle of each rotation is 90 degrees; or the number of rotations of the substrate w is 2, and the set angle of each rotation is 120 degrees; or the number of rotations of the substrate w is 1, and the set angle of each rotation is 180 degrees. The deposition rate of the thin film on the substrate w is related to a multiple of the radio frequency power of the radio frequency source 9, the high frequency of the radio frequency source 9 is an integer multiple n of 13.56 MHz, where n = 1, 2, 3, ..., 8, and the low frequency range of the radio frequency source 9 is 20 kHz to 400 kHz.

[0050] However, during the rotation of the substrate w, if the radio frequency source 9 remains in the ON state and the substrate w detaches from the heating tray 3, the gap between the back surface of the substrate w and the heating tray 3 becomes too large, making it easy for an arc discharge phenomenon to occur. Therefore, in a specific embodiment, when the radio frequency source 9 is in the ON state, in order to prevent the substrate w from detaching from the heating tray 3 and causing an arc discharge phenomenon, it is necessary to adjust the gap between the substrate w and the heating tray 3 to be less than the set value so that, in a plasma gas atmosphere, the substrate w does not detach from the heating tray 3 and no arc discharge phenomenon occurs. In a specific embodiment, the set value of the gap between the substrate w and the heating tray 3 is m, and 0 < m ≤ 5 mm. Therefore, when the gap between the substrate w and the heating tray 3 is smaller than the set value, by keeping the radio frequency source 9 in the ON state, the risk of arc discharge occurring on the substrate w is reduced, ensuring the safety and stability of the thin film deposition process.

[0051] The present invention further provides a second specific embodiment of a thin film deposition apparatus. As shown in FIG. 4, the thin film deposition apparatus includes a processing cavity 1, a gas ejection port 2, a heating tray 3, a flow guiding ring 5, and a radio frequency source 9. The processing cavity 1 is used to perform a thin film deposition process on the substrate w. The gas ejection port 2 is provided on the top wall of the processing cavity 1, and a plurality of air outlets 201 are opened in the gas ejection port 2 to form an air outlet region, and as shown in FIG. 6A, it is used to supply a process gas into the processing cavity 1. The heating tray 3 is disposed below the gas ejection port 2 and is used to carry and heat the substrate w. The radio frequency source 9 is used to supply radio frequency power, form a radio frequency electric field inside the processing cavity 1, excite the process gas inside the processing cavity 1 to dissociate it into plasma gas, and deposit a thin film on the substrate w from the dissociated plasma gas.

[0052] Unlike conventional gas nozzles 2 which are upper electrodes, the gas nozzle 2 in this embodiment is provided independently of the upper electrode 6, the gas nozzle 2 is an insulator, the upper electrode 6 is provided below the gas nozzle 2, the upper electrode and lower electrode are the same size or differ by ±10 mm, and the diameter of the lower electrode 12 is smaller than the diameter of the substrate w but is 15 mm or less, thereby ensuring that a uniform radio frequency electric field is formed between the upper electrode and the lower electrode, i.e., within the reaction region, and that the thin film deposited on the substrate w becomes more uniform. Considering that it is necessary to introduce process gas into the reaction region, the upper electrode 6 is configured as a mesh electrode, and the diameter of the air outlet region of the gas nozzle 2 must be greater than or equal to the diameter of the mesh electrode. In addition, in this embodiment, in order to stabilize the airflow in the processing cavity 1, a flow guide ring 5 is added around the side of the upper electrode 6, and the material of the flow guide ring 5 is preferably AlN or Al2O3.

[0053] Other settings in this embodiment are the same as in Embodiment 1 and are therefore omitted here.

[0054] The present invention further provides a third specific embodiment of a thin film deposition apparatus. As shown in Figure 5, the gas nozzle 2 of Embodiment 3 is provided independently of the upper electrode, the gas nozzle 2 is an insulator, and the bottom of the gas nozzle 2 has a groove. The air outlet 201 of the gas nozzle 2 is located in the bottom groove, and the upper electrode 6 is located in the groove. The air outlet 201 in this embodiment may be made of a metal material and serves to conduct heat. Preferably, the gas nozzle 2 completely encloses the side wall of the upper electrode 6. The upper electrode 6 needs to be configured as a mesh electrode, considering that process gas needs to be introduced into the reaction region. The groove opened by the gas nozzle 2 may have multiple shapes, and it is preferable that the groove be circular in order to make better contact with the upper electrode 6. In order to better enclose the side wall of the upper electrode 6, the diameter of the groove is the same as the diameter of the upper electrode 6.

[0055] In this embodiment, if the gas nozzle 2 is configured as an insulator with a groove in the middle and electrodes are placed in the groove, the flow guide ring 5 is not required, and the function of the flow guide ring 5 in the aforementioned embodiment 5 can be achieved by the protruding step of the gas nozzle 2.

[0056] As shown in Figures 6A and 6B, a mesh electrode is installed below the gas nozzle 2, and the ventilation holes of the mesh electrode communicate with the air outlet of the gas nozzle 2. This not only generates a uniform electric field with the lower electrode 12, but also allows for the efficient introduction of a uniform process gas.

[0057] Other settings in this embodiment are the same as in Embodiment 1 and are therefore omitted here.

[0058] The present invention further provides a fourth specific embodiment of a thin film deposition apparatus. This thin film deposition apparatus comprises a processing cavity 1, a gas nozzle 2, a heating tray 3, and a radio frequency source 9. The processing cavity 1 is used to perform a thin film deposition process on a substrate w, and the gas nozzle 2 is provided on the top wall of the processing cavity 1, and a plurality of air outlets 201 are opened in the gas nozzle 2 to form an air outlet region, which is used to supply process gas into the processing cavity 1 as shown in Figure 7A. The heating tray 3 is positioned below the gas nozzle 2 and is used to support and heat the substrate w, and the radio frequency source 9 is used to supply radio frequency power, which forms a radio frequency electric field inside the processing cavity 1, excites the process gas inside the processing cavity 1 and dissociates it into plasma gas, and deposits a thin film on the substrate w with the dissociated plasma gas.

[0059] This device further includes a support ring 4 and a rotational lifting mechanism 8 to make the thin film on the substrate w more uniform. The support ring 4 supports the substrate w and extends outward from the substrate w. On the other hand, the support ring 4 is an insulator and can not only support the substrate w but also shield against electric field leakage from the lower electrode 12, preventing the electric field from extending or reactions from occurring.

[0060] In this embodiment, an insulating plate 7 is further provided below the gas nozzle 2, and a plurality of ventilation holes 701 are opened in the insulating plate 7. The ventilation holes 701 communicate with the air outlet 201 of the gas nozzle 2 and are for introducing process gas into the processing cavity 1. In order to make the process gas introduced into the processing cavity 1 more uniform, the number and diameter of the air outlet 201 of the gas nozzle 2 and the ventilation holes 701 are the same, and their positions correspond one-to-one.

[0061] In conventional technology, an insulating coating is applied below the gas nozzle 2 to reduce the occurrence of thin film deposition due to the reaction of the metal gas nozzle 2 with the gas, and the thickness of this coating is approximately 0.2 mm or less. In the present invention, an insulating plate 7 having a certain thickness is selected, and the insulating plate 7 and the gas nozzle 2 are not integrally molded. The thickness of the insulating plate 7 is 0.2 mm or more, and more preferably 5 mm or more. The insulating plate 7 in the present invention differs from the function of conventional insulating layers in that it deposits a thin film on the insulating plate 7 similar to that on the substrate. Quartz and silicon may be added to the insulating plate 7, and the quartz may be black quartz mixed with silicon powder, which can increase the heat absorption efficiency, raise the temperature of the insulating plate 7, and improve the density of the film. The insulating plate 7 cannot block the AC electric field, and in addition to the spontaneous heat insulation properties of the insulating plate, its temperature is also high, so a thin film is deposited on the insulating plate 7, and the thickness of the thin film is denser, close to that of a thin film deposited on the substrate, making it less prone to breakage and preventing the generation of particulate matter. Furthermore, by mechanically or chemically roughening the surface of the insulating plate 7, the adsorption force between the surface and the thin film diameter can be increased, the thickness of the deposited thin film can be increased, and the frequency of cleaning the processing cavity can be reduced.

[0062] Referring to Figures 7A and 7B, the insulating plate 7 may be in contact with the bottom surface of the gas nozzle 2, or a gap may be left between it and the bottom surface of the gas nozzle 2. In Figure 7A, the insulating plate 7 is positioned in contact with the bottom surface of the gas nozzle 2. Because the gas nozzle 2 is made of metal, it has good thermal conductivity, so the insulating plate 7 does not become excessively hot, resulting in good temperature uniformity. As the temperature is close to the process temperature of the substrate, the thin film deposited on the insulating plate 7 is also closer to the thin film deposited on the substrate.

[0063] Figure 7B shows an arrangement where a gap 11 is left between the insulating plate 7 and the gas nozzle 2, with the size of the gap 11 being 0.1 to 2 mm. In this embodiment, because the gap 11 is too small, there is little plasma that can enter the gap 11, and it is completely or partially adsorbed by the insulating plate 7, so no or minimal deposition occurs on the electrode. If the gap 11 is too large, the insulating plate 7 cannot adsorb the plasma, and excess plasma enters the gap 11, causing deposition on the electrode and increasing the frequency of cleaning. Since it is undesirable for a gap 11 to exist between the gas nozzle 2 and the insulating plate 7, and for plasma to enter the gap 11 and react with the electrode, or for a small amount of plasma to enter and react with the electrode, an insulating ring can be used to enclose the gap and block the entry of plasma. Preferably, the insulating ring is molded integrally with the insulating plate 7, and the insulating plate 7 is designed so that its edges extend directly upward to form a U-shaped insulating cover that encloses the gap, preventing plasma from entering from both sides of the gap. The diameter of this U-shaped insulating cover is preferably greater than or equal to the diameter of the lower support ring, so that it can perform the role of a flow guide ring in the above-described embodiment, and the U-shaped insulating cover is provided with ventilation holes 701 only in the portion facing the gas outlet air outlet 201.

[0064] Furthermore, it is preferable that the insulating plate 7 is made of a material that can withstand HF plasma cleaning, such as sapphire or carbonization.

[0065] The thin-film deposition apparatus of this embodiment can reduce particles without cutting the plasma during the process, reduce the number of cleaning cycles, and achieve multilayer film deposition in a single step.

[0066] The present invention, through the description of the embodiments and related drawings described above, specifically and in detail, discloses related technologies that can be implemented by those skilled in the art. The embodiments described above are for illustrative purposes only and are not intended to limit the present invention, and the scope of the present invention should be defined by the claims of the present invention. Changes in the number of parts or substitution of equivalent parts described herein shall still be within the scope of the present invention.

[0067] At the same time, the present invention uses specific terminology to describe embodiments of the present invention. For example, “one embodiment,” “one embodiment,” and / or “some embodiments” mean features, structures, or characteristics relating to at least one embodiment of the present invention. Therefore, it should be emphasized and noted that “one embodiment,” “embodiment,” or “alternative embodiment” mentioned more than once in different places in this specification do not necessarily mean the same embodiment.

[0068] Similarly, it should be noted that, in order to simplify the expression of the disclosure of the present invention and thereby aid in understanding one or more embodiments of the invention, multiple features may be combined into a single embodiment, drawing, or description in the descriptions of the embodiments of the invention described above. However, this method of disclosure does not mean that there are more features required for the subject matter of the invention than those described in the claims. In fact, the features of an embodiment are fewer than the features of all the individual embodiments disclosed above combined.

Claims

1. A processing cavity for thin film deposition, A gas supply assembly is provided on the top wall of the processing cavity for supplying process gas into the processing cavity, A heating tray is provided below the gas supply assembly for supporting and heating the substrate, Upper and lower electrodes for forming a uniform electric field within the processing cavity, The system comprises a radio frequency source connected to the upper and lower electrodes to supply radio frequency power, which excites the process gas inside the processing cavity and dissociates it into a plasma gas, causing the plasma gas to deposit a thin film on the substrate, A thin film deposition apparatus characterized in that the upper electrode and the lower electrode are the same size or have a difference of ±10 mm, and the diameter of the lower electrode is smaller than that of the substrate, and a uniform electric field is generated between the upper electrode and the lower electrode.

2. The thin film deposition apparatus according to claim 1, characterized in that the difference in diameter between the lower electrode and the substrate is 15 mm or less.

3. The thin film deposition apparatus according to claim 1, characterized in that the upper electrode has the same diameter as the substrate or a difference of ±10 mm.

4. The thin film deposition apparatus according to claim 1, further comprising a support ring and a rotating mechanism, wherein the support ring is for supporting a substrate.

5. The thin film deposition apparatus according to claim 4, characterized in that the support ring is an insulator.

6. The thin film deposition apparatus according to claim 5, characterized in that the rotation mechanism is for controlling the rotation of the heating tray relative to the substrate, or the heating tray together with the substrate, or the gas supply assembly relative to the substrate, or the support ring together with the substrate.

7. The thin film deposition apparatus according to claim 5, characterized in that when the rotating mechanism controls the rotation of the substrate, the gas supplied to the processing cavity is an inert gas.

8. The thin film deposition apparatus according to claim 7, characterized in that the inert gas is nitrogen gas.

9. The thin film deposition apparatus according to claim 7, characterized in that the temperature of the inert gas introduced is 200 to 500°C.

10. The thin film deposition apparatus according to claim 4, characterized in that the rotation mechanism turns on the radio frequency source when controlling the rotation of the substrate.

11. The thin film deposition apparatus according to claim 4, further comprising a flow guide ring that encloses the side wall of the upper electrode.

12. The thin film deposition apparatus according to claim 11, characterized in that the diameter of the flow guide ring is greater than or equal to the diameter of the support ring.

13. The thin film deposition apparatus according to claim 11, characterized in that the flow guide ring is an insulator.

14. The material of the flow guide ring is AlN or Al ２ O ３ The thin film deposition apparatus according to claim 13, characterized in that it is the same as the one described above.

15. The thin film deposition apparatus according to claim 1, characterized in that the upper electrode is integrally configured with a gas supply device.

16. The thin film deposition apparatus according to claim 1, characterized in that the gas supply assembly is an insulator, the upper electrode is located below the gas supply assembly, and the upper electrode is a mesh electrode.

17. The thin film deposition apparatus according to claim 1, characterized in that the gas supply assembly is an insulator with a groove at its bottom, the air outlet of the gas supply assembly is located in the groove, and a mesh electrode is further embedded in the groove.

18. The thin film deposition apparatus according to claim 17, characterized in that the groove is a circular groove.

19. The thin film deposition apparatus according to claim 18, characterized in that the diameter of the circular groove is the same as that of the mesh electrode.

20. A processing cavity for thin film deposition, A gas supply assembly is provided on the top wall of the processing cavity for supplying process gas into the processing cavity, A heating tray is provided below the gas supply assembly for supporting and heating the substrate, A radio frequency source that supplies radio frequency power, excites the process gas inside the processing cavity and dissociates it into a plasma gas, and the plasma gas performs thin film deposition on the substrate, A thin film deposition apparatus comprising an insulating plate located below the gas supply assembly and having multiple vents for introducing process gas into the processing cavity.

21. The thin film deposition apparatus according to claim 20, characterized in that the thickness of the insulating plate is 0.2 mm or more.

22. The thin film deposition apparatus according to claim 20, characterized in that the insulating plate is in contact with the bottom surface of the gas supply assembly.

23. The thin film deposition apparatus according to claim 22, characterized in that the ventilation hole has the same diameter as the air outlet diameter.

24. The thin film deposition apparatus according to claim 22, characterized in that the number of ventilation holes is equal to or greater than the number of air outlets.

25. The thin film deposition apparatus according to claim 22, characterized in that each air outlet of the gas supply assembly has a ventilation hole on the insulating plate corresponding to its position.

26. The thin film deposition apparatus according to claim 20, characterized in that a gap is left between the insulating plate and the gas supply assembly, and an insulating ring is attached around the outside of the gap.

27. The thin film deposition apparatus according to claim 26, characterized in that the insulating ring has an edge of insulating plate that extends upward to a side wall enclosing the gas supply assembly.

28. The thin film deposition apparatus according to claim 26, characterized in that the gap between the insulating plate and the gas supply assembly is 0.1 to 2 mm.

29. The thin film deposition apparatus according to claim 20, characterized in that the insulating plate is made of a material that does not react with HF.

30. The thin film deposition apparatus according to claim 29, characterized in that the insulating plate is made of sapphire or silicon carbide material.

31. The thin film deposition apparatus according to claim 29, characterized in that quartz and silicon are added to the insulating plate material.

32. The thin film deposition apparatus according to claim 31, characterized in that the quartz is synthetic quartz mixed with silicon.

33. The thin film deposition apparatus according to claim 20, characterized in that the surface treatment of the insulating plate is to roughen its surface.

34. The thin film deposition apparatus according to claim 20, further comprising a support ring and a rotating mechanism, wherein the support ring is for supporting a substrate and the rotating mechanism is for controlling the rotation of the substrate.

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