Wafer processing equipment and wafer processing methods

Abstract

This invention relates to a wafer processing apparatus and a wafer processing method. The apparatus includes: a housing and a reaction chamber enclosed by the housing; the reaction chamber is divided into an upper chamber and a lower chamber by a filtration device; the filtration device includes a filter baffle with one or more filter holes penetrating the baffle; and a reaction rate control system that controls the opening and partial closing of the filter holes, thereby adjusting the amount of charged particles passing through the plasma and the reaction rate. The processing method uses the above-described processing apparatus. This invention effectively solves the problem of balancing ion damage and processing efficiency in existing technologies by optimizing the plasma filtration and control mechanism, and has significant application value.

Description

Technical Field

[0001] This invention relates to the field of semiconductor manufacturing technology, and in particular to a wafer processing apparatus and a wafer processing method. Background Technology

[0002] Plasma, also known as electroplating, is an ionized gaseous substance composed of positive and negative ions, electrons, free radicals, and central particles generated after the ionization of atoms and atomic groups. It is a macroscopically neutral ionized gas with a scale greater than the Debye length, and its motion is primarily governed by electromagnetic forces, exhibiting significant collective behavior. Plasma has important applications in the semiconductor industry, especially in wafer fabrication, involving various equipment and processes, such as semiconductor plasma resist stripping equipment, plasma etching equipment, and plasma thin film deposition equipment. However, existing equipment using plasma often suffers ion damage to the wafer substrate due to process limitations. Reducing ion damage leads to a decrease in reaction rate. Therefore, achieving a balance between low ion damage and high reaction rate has become a critical technical challenge for existing equipment. Furthermore, as semiconductor manufacturing processes advance towards higher precision and smaller dimensions, the performance requirements for plasma equipment are increasing, further complicating this problem. Summary of the Invention

[0003] Based on this, and to address the aforementioned problems, the present invention provides a wafer processing apparatus and a wafer processing method that effectively reduce ion damage while maintaining high processing efficiency by optimizing the plasma filtration and control mechanism.

[0004] This invention provides a wafer processing apparatus, comprising: a housing and a reaction chamber enclosed by the housing;

[0005] The reaction chamber is divided into an upper chamber and a lower chamber by a filtration device;

[0006] The filtration device includes a filter baffle, which has one or more filter holes penetrating through it.

[0007] It also includes a reaction rate control system, which controls the opening and partial closing of the filter orifice, thereby adjusting the amount of charged particles passing through the plasma and the reaction rate.

[0008] In some embodiments, a first groove is provided on one side wall of each filter hole, and a second groove is provided on the other side wall of the filter hole.

[0009] A first slider is provided in the first groove. The first slider includes a first protrusion and a first connecting part. The first connecting part is slidably connected to the filter baffle. By sliding in the first groove, the first protrusion extends out of the first groove and enters the filter hole.

[0010] A second slider is provided in the second groove. The second slider includes a second protrusion and a second connecting part. The second connecting part is slidably connected to the filter baffle. By sliding in the second groove, the second protrusion extends out of the second groove and enters the filter hole.

[0011] The reaction rate control system controls the sliding of the first slider and the second slider, and controls the opening and partial closing of the filter hole by the intersection and separation of the first protrusion and the second protrusion in the filter hole.

[0012] In some embodiments, the first protrusion includes an upper blocking block and a lower blocking block, the horizontal side length of the upper blocking block and the lower blocking block is not less than the side length of the filter hole; the second protrusion is a protrusion, the distance between the upper blocking block and the lower blocking block is greater than the thickness of the protrusion.

[0013] In some other embodiments, the first protrusion is an upper blocking block and the second protrusion is a lower blocking block. The horizontal side lengths of the upper and lower blocking blocks are not less than the side lengths of the filter holes, and the bottom of the upper blocking block is higher than the top of the lower blocking block in the vertical direction.

[0014] In some other embodiments, each filter hole also includes a blocking sheet, which is rotatably connected to the filter baffle.

[0015] The reaction rate control system controls the rotation of the baffle plate, which in turn controls the opening and partial closing of the filter pores. In some embodiments, the filter baffle is a cylinder that fits against the inner wall of the housing.

[0016] In some embodiments, the filtration device further includes a gas distribution plate disposed below the filter baffle to ensure uniform distribution of plasma passing through the filter baffle, thereby facilitating better operation.

[0017] In some embodiments, an ion density analysis system is also included for real-time monitoring of the density of charged particles, such as ions or electrons, in the plasma arriving at the lower cavity. This system can provide real-time feedback of ion density information in order to adjust the state of the baffle.

[0018] In some embodiments, the ion density analysis system is provided with a detection probe that extends into the lower cavity to detect the ion density; preferably, a Langmuir probe is used.

[0019] In some embodiments, a process gas source is also provided, which is connected to the upper cavity via a pipeline. The process gas includes, but is not limited to, CxFy, O2, Ar, N2, H2, He, etc.

[0020] In some embodiments, a plasma excitation device is also provided to excite the process gas into plasma, which enters the upper cavity and passes through a baffle to reach the lower cavity for operation.

[0021] In some embodiments, the filter baffle is made of a conductor, and the baffle includes an aluminum baffle or an aluminum baffle with a surface coated with aluminum nitride or aluminum oxide, etc.

[0022] In some embodiments, a wafer stage is further provided in the lower cavity, and the wafer to be processed is placed on the wafer stage. During wafer processing, by controlling the filtration state of the filtration device, damage to the wafer substrate by ions can be effectively reduced, while maintaining high processing efficiency.

[0023] In some embodiments, a gas extraction pipe is also provided inside the reaction chamber for discharging gas from the chamber. The gas extraction pipe is connected to a pump to ensure that the pressure and gas composition inside the chamber meet process requirements.

[0024] This application also provides a wafer processing method using the above-described wafer processing apparatus.

[0025] The processing method includes:

[0026] Confirm the operations that need to be performed on the wafer to be processed and the desired wafer product;

[0027] The closing amplitude of the filter apertures at different time periods during wafer processing was designed;

[0028] The wafer to be processed is obtained by adjusting the shut-off range through the reaction rate control system.

[0029] The design methods for the closing amplitude include:

[0030] S1: Establish the relationship curves between D, R, P and the closing amplitude;

[0031] S2: Set the target value D for different times t. t R t P t And determine the selection range of D, R, and P at time t; for example, confirm the target value D at time t0. t0 R t0 P t0 and determine D <D t0 R>R t0 P <P t0 ;

[0032] S3: Substitute the selection range of D, R, and P at time t in S2 into the relationship curve obtained in S1, and design the required closing amplitude at time t;

[0033] Where D is the ion density, R is the reaction rate, and P is the ion damage per unit reaction rate, P=D / R; the shut-off range is less than 100%, where open is 0%, and 0% < partially shut-off < 100%.

[0034] In some embodiments, the processing method includes growing a thin film on a wafer or removing a thin film from a wafer.

[0035] In some embodiments, the closing range can be fixed at different time periods, for example:

[0036] When removing the thin film on the wafer, the sliding of the first slider and the second slider is controlled so that the first protrusion and the second protrusion enter the groove, so that the filter hole is fully opened; when approaching the termination interface, the sliding of the first slider and the second slider is controlled so that the first protrusion and the second protrusion enter the filter hole, so that the filter hole is partially closed.

[0037] When growing a thin film on a wafer, the sliding of the first slider and the second slider is controlled so that the first protrusion and the second protrusion enter the filter hole, thus partially closing the filter hole. After growing a thin film of a certain thickness, the control device controls the sliding of the first slider and the second slider so that the first protrusion and the second protrusion enter the groove, thus fully opening the filter hole. When the growth is almost complete, the sliding of the first slider and the second slider is controlled so that the first protrusion and the second protrusion enter the filter hole, thus partially closing the filter hole.

[0038] In other embodiments, the closing amplitude can be continuously adjusted, but it is necessary to satisfy the selection range of D, R, and P at different times.

[0039] In the aforementioned wafer processing apparatus, the filter orifice is partially closed when low ion damage and low reaction rate are required, and opened when high reaction rate is required. Ion damage can be monitored in real time by an ion density analysis system, and the opening and closing of the filter orifice can be adjusted in real time. This achieves the effect of controlling both reaction rate and ion damage. This invention effectively solves the problem of balancing ion damage and processing efficiency in existing technologies by optimizing the plasma filtration and control mechanism, and has significant application value. Attached Figure Description

[0040] Figure 1 This is a schematic diagram of the wafer processing apparatus of the present invention;

[0041] Figure 2 This is a schematic diagram of the structure of a filter baffle in one embodiment of the present invention;

[0042] Figure 3 This is a schematic diagram of the structure when the first slider and the second slider partially close the filter hole in one embodiment of the present invention;

[0043] Figure 4 In one embodiment of the present invention, the first slider and the second slider connect the filter hole with... Figure 3 A schematic diagram of the structure when the partial closure amplitude is different;

[0044] Figure 5This is a schematic diagram of the structure when the first slider and the second slider open the filter hole in one embodiment of the present invention;

[0045] Figure 6 This is a schematic diagram of the structure when the first slider and the second slider partially close the filter hole in another embodiment of the present invention;

[0046] Figure 7 This is a schematic diagram of the structure when the first slider and the second slider partially close the filter hole in another embodiment of the present invention;

[0047] Figure 8 This is a schematic diagram of the structure when the blocking sheet partially closes the filter holes to different degrees in another embodiment of the present invention.

[0048] Reference numerals: 1-Shell; 2-Upper cavity; 3-Lower cavity; 4-Filter baffle; 5-Gas distribution plate; 6-Process gas source; 7-Plasma excitation device; 8-Ion density analysis system; 9-Detection probe; 10-Wafer to be processed; 11-Wafer stage; 12-Evacuation pipe;

[0049] 41-First slider; 42-Second slider; 43-Blocking plate; 44-Rotating shaft. Detailed Implementation

[0050] To facilitate understanding of the present invention, a more complete description will be given below with reference to the accompanying drawings. Preferred embodiments of the invention are shown in the drawings. However, the invention can be implemented in many different forms and is not limited to the embodiments described herein. These embodiments are provided so that this disclosure will be thorough and complete.

[0051] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0052] In the description of this invention, it should be understood that the terms "upper", "lower", "vertical", "horizontal", "inner", "outer", etc., indicate the orientation or positional relationship based on the method or positional relationship shown in the drawings, and are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0053] In plasma etching and plasma resist removal processes, some processes have strict requirements for ion damage. Excessive plasma density can lead to severe ion bombardment of the substrate and excessive charge accumulation on the substrate, causing substrate breakdown damage. On the other hand, some processes require a high reaction rate, and the substrate surface film is stable and hard enough that ion bombardment will not damage the substrate. In this case, increasing the ion density can improve the reaction activity and increase the reaction rate.

[0054] This invention provides a wafer processing apparatus, such as... Figure 1 As shown, it includes a shell 1 and a reaction chamber enclosed by the shell 1;

[0055] The reaction chamber is divided into an upper chamber 2 and a lower chamber 3 by a filtration device;

[0056] The filtration device includes a filter baffle 4, such as Figure 2 The filter baffle 4 shown is provided with multiple filter holes that penetrate the filter baffle 4.

[0057] It also includes a reaction rate control system, which controls the opening and partial closing of the filter orifice, thereby adjusting the amount of charged particles passing through the plasma and the reaction rate.

[0058] In some embodiments, a first groove is provided on one side wall of each filter hole, and a second groove is provided on the other side wall of the filter hole.

[0059] A first slider 41 is provided in the first groove. The first slider 41 includes a first protrusion and a first connecting part. The first connecting part is slidably connected to the filter baffle 4. By sliding in the first groove, the first protrusion extends out of the first groove and enters the filter hole.

[0060] A second slider 42 is provided in the second groove. The second slider 42 includes a second protrusion and a second connecting part. The second connecting part is slidably connected to the filter baffle 4. By sliding in the second groove, the second protrusion extends out of the second groove and enters the filter hole.

[0061] The reaction rate control system controls the sliding of the first slider 41 and the second slider 42, and controls the opening and partial closing of the filter hole by the intersection and separation of the first protrusion and the second protrusion in the filter hole.

[0062] In some embodiments, the first slider 41 and the second slider 42 are both integrally formed.

[0063] like Figures 3-5 As shown, in some embodiments, the first protrusion includes an upper blocking block and a lower blocking block, the horizontal side length of which is not less than the side length of the filter hole; the second protrusion is a protrusion, the distance between the upper blocking block and the lower blocking block is greater than the thickness of the protrusion.

[0064] like Figure 6 and Figure 7 As shown, in some other embodiments, the first protrusion is an upper blocking block and the second protrusion is a lower blocking block. The horizontal side length of the upper and lower blocking blocks is not less than the side length of the filter hole, and the bottom of the upper blocking block is higher than the top of the lower blocking block in the vertical direction.

[0065] like Figure 8 As shown, in some other embodiments, each filter hole also includes a baffle plate 43, and a rotating shaft 44 is provided on the baffle plate 43 through the diameter direction of the baffle plate 43. The baffle plate 43 and the filter baffle 4 are rotatably connected through the rotating shaft 44.

[0066] The reaction rate control system controls the rotation of the baffle plate 43, and the rotation of the baffle plate 43 controls the opening and partial closing of the filter holes. Figure 8 (A) and (B) in the figure represent the different closing states of the filter holes when the baffle plate 43 rotates at different amplitudes.

[0067] In some embodiments, the filter baffle 4 is a cylinder and is fitted to the inner wall of the housing 1. In some embodiments, the filtration device further includes a gas distribution plate 5 disposed below the filter baffle 4 to ensure uniform distribution of the plasma passing through the filter baffle 4, facilitating better operation.

[0068] In some embodiments, an ion density analysis system 8 is also included, which is used to monitor the density of charged particles, such as ion or electron density, in the plasma arriving at the lower cavity 3 in real time. It can provide real-time feedback of ion density information so as to adjust the state of the filter baffle 4.

[0069] In some embodiments, the ion density analysis system 8 is provided with a detection probe 9, which extends into the lower cavity 3 to detect the ion density; preferably, a Langmuir probe is used.

[0070] In some embodiments, a process gas source 6 is also provided, which is connected to the upper cavity 2 via a pipeline. The process gas includes, but is not limited to, CxFy, O2, Ar, N2, H2, He, etc.

[0071] In some embodiments, a plasma excitation device 7 is also provided, which is used to excite the process gas into plasma, which enters the upper cavity 2 and passes through the filter baffle 4 to reach the lower cavity 3 for operation.

[0072] In some embodiments, the filter baffle 4 is made of a conductor, and the baffle includes an aluminum baffle or an aluminum baffle with a surface coated with aluminum nitride or aluminum oxide, etc.

[0073] In some embodiments, a wafer stage 11 is further provided in the lower cavity 3, and the wafer 10 to be processed is placed on the wafer stage 11. During the processing of the wafer 10, by controlling the filtration state of the filtration device, damage to the wafer substrate by ions can be effectively reduced, while maintaining high processing efficiency.

[0074] In some embodiments, a suction pipe 12 is also provided at the bottom of the lower cavity 3 for discharging gas from the cavity. The suction pipe 12 is connected to a pump to ensure that the pressure and gas composition in the cavity meet the process requirements.

[0075] This application also provides a wafer processing method using the above-described wafer processing apparatus.

[0076] The processing method includes:

[0077] Confirm the operations to be performed on wafer 10 and the desired wafer product;

[0078] The closing amplitude of the filter apertures at different time periods during the processing of wafer 10 is designed;

[0079] The closure amplitude is adjusted by the reaction rate control system to process the wafer 10 to obtain the wafer product.

[0080] The design methods for the closing amplitude include:

[0081] S1: Establish the relationship curves between D, R, P and the closing amplitude;

[0082] S2: Set the target value D for different times t. t R t P t And determine the selection range of D, R, and P at time t; for example, confirm the target value D at time t0. t0 R t0 P t0 and determine D <D t0 R>R t0 P <P t0 ;

[0083] S3: Substitute the selection range of D, R, and P at time t in S2 into the relationship curve obtained in S1, and design the required closing amplitude at time t;

[0084] Where D is the ion density, R is the reaction rate, and P is the ion damage per unit reaction rate, P = D / R; the shut-off range is less than 100%, where open is 0%, and 0% < partial shut-off < 100%. Figure 3 As shown, when the filter pores are partially closed, almost all ions have no direct path from top to bottom, resulting in the highest probability and frequency of contact with the slider wall, leading to extremely strong ion filtering capacity and the slowest reaction rate; Figure 4 As shown, the filter holes are also partially closed, but the closure extent is less than that of the filter holes. Figure 3 Almost all ions have no direct path from top to bottom, resulting in a moderate probability and frequency of contact with the slider wall, moderate ion filtering capacity, and moderate reaction rate; Figure 5 As shown, when the filter holes are open, a large number of ions have a direct path from top to bottom, resulting in weak ion filtration capacity and a fast reaction rate. At the same time, the reaction rate can be further controlled by adjusting the opening space of the filter holes.

[0085] In some embodiments, the processing method includes growing a thin film on a wafer or removing a thin film from a wafer.

[0086] In some embodiments, the closing range can be fixed at different time periods, for example:

[0087] When removing the film on the wafer 10 to be processed, the sliding of the first slider 41 and the second slider 42 is controlled so that the first protrusion and the second protrusion enter the groove, so that the filter hole is fully opened; when approaching the termination interface, the sliding of the first slider 41 and the second slider 42 is controlled so that the first protrusion and the second protrusion enter the filter hole, so that the filter hole is partially closed.

[0088] When growing a thin film on the wafer 10 to be processed, the sliding of the first slider 41 and the second slider 42 is controlled so that the first protrusion and the second protrusion enter the filter hole, thus closing the filter hole; after growing a thin film of a certain thickness, the control device controls the sliding of the first slider 41 and the second slider 42 so that the first protrusion and the second protrusion enter the groove, thus fully opening the filter hole; when the growth is almost complete, the sliding of the first slider 41 and the second slider 42 is controlled so that the first protrusion and the second protrusion enter the filter hole, thus partially closing the filter hole.

[0089] In other embodiments, the closing amplitude can be continuously adjusted, but it is necessary to satisfy the selection range of D, R, and P at different times.

[0090] The processing method includes growing a thin film on the wafer 10 to be processed or removing a thin film from the wafer 10 to be processed.

[0091] In some embodiments, when removing the film on the wafer 10 to be processed, the sliding of the first slider 41 and the second slider 42 is controlled so that the first protrusion and the second protrusion enter the groove, so that the filter hole is fully opened; when approaching the termination interface, the sliding of the first slider 41 and the second slider 42 is controlled so that the first protrusion and the second protrusion enter the filter hole, so that the filter hole is partially closed.

[0092] When growing a thin film on the wafer 10 to be processed, the sliding of the first slider 41 and the second slider 42 is controlled so that the first protrusion and the second protrusion enter the filter hole, thus closing the filter hole. After growing a thin film of a certain thickness, the control device controls the sliding of the first slider 41 and the second slider 42 so that the first protrusion and the second protrusion enter the groove, thus fully opening the filter hole. When the growth is almost complete, the sliding of the first slider 41 and the second slider 42 is controlled so that the first protrusion and the second protrusion enter the filter hole, thus partially closing the filter hole. This can reduce the damage of ions to the substrate while ensuring a high reaction rate.

[0093] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0094] The above embodiments merely illustrate several implementation methods of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A wafer fabrication method, characterized in that, Includes the following steps: A filter baffle is provided in the reaction chamber of a wafer processing apparatus. The wafer processing apparatus includes a housing and a reaction chamber enclosed by the housing. The reaction chamber is divided into an upper chamber and a lower chamber by a filter device. The filter device includes a filter baffle with one or more filter holes penetrating it. Each filter hole has a first groove on one side wall and a second groove on the opposite side wall. A first slider, including a first extension and a first connecting portion, is provided in the first groove. A second slider, including a second extension and a second connecting portion, is provided in the second groove. Each filter hole also has a blocking plate with a rotating shaft extending through its diameter. The blocking plate and the filter are rotatably connected via the rotating shaft. A reaction rate control system is provided in the reaction chamber. The reaction rate control system controls the opening and partial closing of the filter holes by controlling the relative movement of the first and second sliders (away from each other) and / or the rotational movement of the blocking plate, thereby adjusting the reaction rate. Confirm the operations that need to be performed on the wafer to be processed and the desired wafer product; The closure range of the filter apertures at different time periods during wafer processing is designed. The design method for the closure range includes: S1: Establishing a relationship curve between D, R, P and the closure range; S2: Setting target values ​​Dt, Rt, and Pt for different time t, and determining the selection range of D, R, and P at that time t; S3: Substituting the selection range of D, R, and P at time t in S2 into the relationship curve obtained in S1, designing the required closure range at time t; where D is the ion density, R is the reaction rate, P is the ion damage per unit reaction rate, and P = D / R; the closure range is less than 100%, where 0% is open and 0% < partially closed < 100%. The reaction rate control system adjusts the closing amplitude by controlling the movement of the first slider, the second slider, and the blocking plate according to preset process parameters such as time T, ion density D, reaction rate R, and ion damage P, so as to process the wafer to obtain the wafer product. Specifically, when a high reaction rate is required, the reaction rate control system controls the sliding of the first and second sliders, causing the first and second protrusions to enter the grooves, and / or the reaction rate control system controls the rotation of the blocking plate to fully open the filter holes; when low ion damage and a low reaction rate are required, the reaction rate control system controls the sliding of the first and second sliders, causing the first and second protrusions to enter the filter holes, and / or the reaction rate control system controls the rotation of the blocking plate to partially close the filter holes; wherein, the ion density analysis system monitors the charged ion or electron density in the plasma reaching the lower cavity in real time, providing real-time feedback of ion density information to monitor ion damage.

2. The wafer fabrication method according to claim 1, characterized in that, The first connecting part is slidably connected to the filter baffle, and the first protruding part extends out of the first groove and enters the filter hole by sliding in the first groove; the second connecting part is slidably connected to the filter baffle, and the second protruding part extends out of the second groove and enters the filter hole by sliding in the second groove.

3. The wafer fabrication method according to claim 1, characterized in that, The first protrusion includes an upper blocking block and a lower blocking block, the horizontal side length of which is not less than the side length of the filter hole; the second protrusion is a protrusion, the distance between the upper blocking block and the lower blocking block is greater than the thickness of the protrusion.

4. The wafer fabrication method according to claim 1, characterized in that, The filter baffle is made of a conductor and includes an aluminum baffle or an aluminum baffle with a surface coated with aluminum nitride or aluminum oxide.

5. The wafer fabrication method according to claim 1, characterized in that, The first protrusion is an upper blocking block, and the second protrusion is a lower blocking block. The horizontal side length of the upper and lower blocking blocks is not less than the side length of the filter hole, and the bottom of the upper blocking block is higher than the top of the lower blocking block in the vertical direction.

6. The wafer fabrication method according to claim 1, characterized in that, The filtration device also includes a gas distribution plate disposed below the filter baffle.

7. The wafer fabrication method according to claim 1, characterized in that, The ion density analysis system is equipped with a detection probe that extends into the lower cavity to detect the ion density.

8. The wafer fabrication method according to claim 1, characterized in that, It also includes a process gas source and a plasma excitation device, wherein the process gas source and the upper cavity are connected by a pipeline; the plasma excitation device is used to excite the process gas into plasma and enter the upper cavity. The lower cavity is also provided with a wafer stage, and the wafer to be processed is placed on the wafer stage; The lower cavity is also equipped with an air extraction pipe for venting gas from the cavity.

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