Etching equipment and pressure control method thereof

Abstract

The present invention relates to the field of semiconductor technology, and discloses an etching device and a pressure control method thereof. An etching cavity is formed in an etching body of the etching device; a pressure control unit includes an upper pressure control ring and a lower pressure control ring, a limiter is provided on the etching body, and the upper pressure control ring is placed on the limiter or on the upper surface of the lower pressure control ring; a driving member of the driving unit is used to drive the lower pressure control ring to move in the up and down directions; the control unit includes a detection component, and when the detection component detects that the pressure in the etching cavity is a first preset pressure, the driving member can drive the lower pressure control ring to move at a first preset speed; when the detection component detects that the pressure in the etching cavity is a second preset pressure, the driving member can drive the lower pressure control ring to move at a second preset speed, so that the air pressure in the etching cavity is dynamically stable to maintain the working pressure, and the first preset speed is greater than the second preset speed. The present invention controls the moving speed of the pressure control unit according to the real-time pressure value in the etching cavity, and the pressure control effect is better.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor technology, and in particular to an etching device and a voltage control method thereof. Background Art

[0002] In the field of semiconductor technology, advanced process technology requires stable vacuum pressure, so the market needs a precise pressure control structure and pressure control method to improve the process of etching wafers.

[0003] In the prior art, in order to stabilize the vacuum pressure, the pressure control action of the pressure control structure is always consistent and has little correlation with the vacuum degree, resulting in poor pressure control effect when the vacuum degree is close to the working pressure.

[0004] Therefore, there is an urgent need for an etching device and a voltage control method thereof to solve the above problems. Summary of the invention

[0005] Based on the above, the purpose of the present invention is to provide an etching device and a pressure control method thereof, which controls the moving speed of the pressure control unit according to the real-time pressure value in the etching chamber, and has a better pressure control effect.

[0006] To achieve the above object, the present invention adopts the following technical solutions:

[0007] Etching equipment, including:

[0008] An etching body, in which an etching cavity is formed, and an upper silicon ring is provided at an opening end of the etching body;

[0009] A pressure control unit, comprising an upper pressure control ring and a lower pressure control ring, wherein a limiter is arranged on the etching body, the upper pressure control ring is placed on the limiter or on the upper surface of the lower pressure control ring, and a gas channel is formed at least at one place between the upper pressure control ring and the upper silicon ring, between the upper pressure control ring and the lower pressure control ring, and between the lower pressure control ring and the etching body;

[0010] A driving unit, comprising a driving member, wherein the driving member is used to drive the lower pressure control ring to move in an up-down direction;

[0011] A control unit includes a detection component, the drive member is communicatively connected to the detection component, when the detection component detects that the pressure in the etching chamber is a first preset pressure, the drive member can drive the lower control pressure ring to move at a first preset speed; when the detection component detects that the pressure in the etching chamber is a second preset pressure, the drive member can drive the lower control pressure ring to move at a second preset speed, so that the air pressure in the etching chamber dynamically and stably maintains a working pressure, and the first preset speed is greater than the second preset speed.

[0012] As a preferred solution of the etching equipment, the detection component includes a first vacuum gauge and a second vacuum gauge connected to the etching chamber, the second vacuum gauge forms a detection pipeline, the detection pipeline also includes a first switch valve, the first switch valve is arranged between the second vacuum gauge and the etching chamber, and is communicatively connected to the control unit, and the first switch valve is used to selectively connect the second vacuum gauge and the etching chamber.

[0013] As a preferred solution of the etching equipment, the detection pipeline also includes a first vacuum detection component, which is arranged between the first switch valve and the etching chamber and is communicatively connected to the first switch valve. When the first vacuum detection component detects that the air pressure in the etching chamber is less than or equal to its maximum measured value, the first switch valve opens.

[0014] As a preferred solution of the etching equipment, the detection pipeline also includes a second vacuum detection component, which is arranged between the first switch valve and the etching chamber. The etching body is provided with a transmission valve, and the second vacuum detection component is communicatively connected with the transmission valve. When the second vacuum detection component detects that the air pressure in the etching chamber is greater than its maximum measured value, the transmission valve opens.

[0015] As a preferred solution of the etching equipment, the etching equipment includes a dry pump, and a first pipeline and a second pipeline arranged in parallel between the dry pump and the etching chamber, the first pipeline is provided with a molecular pump and a second switch valve located between the molecular pump and the dry pump, the second pipeline is provided with a third switch valve, the second switch valve and the third switch valve are both communicatively connected to the detection component, and the second pipeline is used to pre-vacuum the etching chamber.

[0016] As a preferred solution for the etching equipment, when the first vacuum gauge detects that the pressure of the etching chamber is less than or equal to a third preset pressure, the third switch valve is closed and the second switch valve is opened; when the first vacuum gauge detects that the pressure of the etching chamber is less than or equal to a fourth preset pressure, the first switch valve is opened until the second vacuum gauge detects that the pressure of the etching chamber is the fourth preset pressure, and the third preset pressure is greater than the fourth preset pressure.

[0017] As a preferred solution of the etching equipment, the driving unit also includes a cam, a rotating ring and a connecting rod. The rotating ring cooperates with the cam, and the connecting rod is connected to the lower control pressure ring and the cam. When the driving member drives the rotating ring to rotate, the cam and the connecting rod drive the lower control pressure ring to move in the up and down directions.

[0018] As a preferred solution of the etching equipment, the etching equipment further includes a process gas supply device, the process gas supply device is selectively connected to the etching chamber via a fourth switch valve, and the fourth switch valve is communicatively connected to the control unit.

[0019] A pressure control method for an etching device, used for the etching device as described in any of the above schemes, the pressure control method comprises the following steps:

[0020] Evacuating the etching chamber;

[0021] Setting a first preset pressure, a second preset pressure and a working pressure;

[0022] Introducing a process gas into the etching chamber to make the first preset pressure in the etching chamber;

[0023] The pressure control unit controls the pressure at a first preset speed until the second preset pressure is reached in the etching chamber;

[0024] The pressure control unit controls the pressure at a second preset speed until the working pressure in the etching chamber is reached.

[0025] As a preferred solution of the pressure control method of the etching equipment, evacuating the etching chamber specifically includes:

[0026] Pre-evacuating the etching chamber by a dry pump;

[0027] The etching chamber is evacuated by the dry pump and the molecular pump;

[0028] The detection pipeline is opened, and the detection pipeline and the etching chamber are evacuated by the dry pump and the molecular pump.

[0029] The beneficial effects of the present invention are:

[0030] The present invention provides a pressure control unit, specifically a driving unit that drives the lower pressure control ring to move according to the real-time detection pressure of the detection component, and dynamically adjusts the gas channels between the upper pressure control ring and the upper silicon ring, between the upper pressure control ring and the lower pressure control ring, and between the lower pressure control ring and the etching body, thereby realizing the regulation and control of the pressure in the etching chamber, so that the pressure in the etching chamber can be stably maintained at the working pressure, the surface pressure of the wafer in the etching chamber is consistent, and the etching uniformity is better, thereby improving the market competitiveness of the equipment. Among them, when the detection component detects that the pressure in the etching chamber is a first preset pressure, the driving component can drive the lower pressure control ring to move at a first preset speed; when the detection component detects that the pressure in the etching chamber is a second preset pressure, the driving component can drive the lower pressure control ring to move at a second preset speed, and the first preset speed is greater than the second preset speed, that is, the pressure control unit starts to adjust the pressure in the etching chamber only after the difference between the pressure in the etching chamber and the working pressure reaches a certain level, and the moving speed is faster at this time; and after the difference between the pressure in the etching chamber and the working pressure becomes smaller to a certain level, it is adjusted at a slower moving speed, the adjustment accuracy is higher, and the pressure control effect is better. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments of the present invention. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the contents of the embodiments of the present invention and these drawings without paying any creative work.

[0032] Figure 1 is a schematic diagram of an etching device provided in a specific embodiment of the present invention;

[0033] Figure 2 It is a partial schematic diagram of a pressure control unit of an etching device provided in a specific embodiment of the present invention;

[0034] Figure 3 is a schematic diagram of a pressure control unit of an etching device provided by a specific embodiment of the present invention when placed in different positions;

[0035] Figure 4 is a schematic diagram of an etching device provided in a specific embodiment of the present invention;

[0036] Figure 5 It is a flow chart of a pressure control method for etching equipment provided in a specific embodiment of the present invention.

[0037] In the figure:

[0038] 110, etching body; 111, etching cavity; 112, transmission valve; 113, limiting hole; 114, energy-gathering aluminum ring; 120, upper silicon ring; 130, upper cover;

[0039] 200, pressure control unit; 210, upper pressure control ring; 211, perforated portion; 212, limit flange; 220, lower pressure control ring;

[0040] 300, driving unit; 310, connecting rod;

[0041] 411, first vacuum gauge; 420, detection pipeline; 421, second vacuum gauge; 422, first switch valve; 423, first vacuum detection element; 424, second vacuum detection element; 430, dry pump; 440, first pipeline; 441, molecular pump; 442, second switch valve; 450, second pipeline; 451, third switch valve; 452, third vacuum gauge;

[0042] 500. Process gas supply device; 510. Fourth switch valve. DETAILED DESCRIPTION

[0043] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0044] In the description of the present invention, it should be noted that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance. Among them, the terms "first position" and "second position" are two different positions.

[0045] Unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection or a detachable connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0046] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0047] The technical solution of the present invention is further described below with reference to the accompanying drawings and through specific implementation methods.

[0048] like Figure 1-Figure 4 As shown, this embodiment provides an etching device, which includes an etching body 110, a pressure control unit 200, a driving unit 300 and a control unit. An etching cavity 111 is formed in the etching body 110, and an upper silicon ring 120 is arranged at the open end of the etching body 110; the pressure control unit 200 includes an upper pressure control ring 210 and a lower pressure control ring 220. A limiting member is arranged on the etching body 110, and the upper pressure control ring 210 is placed on the limiting member or on the upper surface of the lower pressure control ring 220. There are two surfaces between the upper pressure control ring 210 and the upper silicon ring 120, between the upper pressure control ring 210 and the lower pressure control ring 220, and between the lower pressure control ring 220 and the etching body 110. A gas channel is formed at least at one place; the driving unit 300 includes a driving member, which is used to drive the lower pressure control ring 220 to move in the up and down directions; the control unit includes a detection component, and the driving member is communicatively connected with the detection component. When the detection component detects that the pressure in the etching chamber 111 is a first preset pressure, the driving member can drive the lower pressure control ring 220 to move at a first preset speed; when the detection component detects that the pressure in the etching chamber 111 is a second preset pressure, the driving member can drive the lower pressure control ring 220 to move at a second preset speed, so that the air pressure in the etching chamber 111 dynamically and stably maintains the working pressure, and the first preset speed is greater than the second preset speed.

[0049] By setting up the pressure control unit 200, specifically by driving the lower pressure control ring 220 according to the real-time detection pressure of the detection component through the driving unit 300, the gas channels between the upper pressure control ring 210 and the upper silicon ring 120, between the upper pressure control ring 210 and the lower pressure control ring 220, and between the lower pressure control ring 220 and the etching body 110 are dynamically adjusted, thereby realizing the adjustment and control of the pressure in the etching chamber 111, so that the pressure in the etching chamber 111 can be stably maintained at the working pressure, so that the surface pressure of the wafer in the etching chamber 111 is consistent, thereby improving the etching uniformity and enhancing the market competitiveness of the equipment. Among them, when the detection component detects that the pressure in the etching chamber 111 is a first preset pressure, the driving component can drive the lower pressure control ring 220 to move at a first preset speed; when the detection component detects that the pressure in the etching chamber 111 is a second preset pressure, the driving component can drive the lower pressure control ring 220 to move at a second preset speed, and the first preset speed is greater than the second preset speed, that is, the pressure control unit 200 starts to adjust the pressure in the etching chamber 111 only after the difference between the pressure in the etching chamber 111 and the working pressure reaches a certain level, and the moving speed is faster at this time; and after the difference between the pressure in the etching chamber 111 and the working pressure becomes smaller to a certain level, it is adjusted at a slower moving speed, the adjustment accuracy is higher, and the pressure control effect is better.

[0050] Optionally, both the upper pressure control ring 210 and the lower pressure control ring 220 are made of quartz rings to reduce the reaction with the process gas and achieve more stable performance. The driving member is used to drive the lower pressure control ring 220 to move in the up and down directions. That is, the upper driving member has no driving force and only descends by its own weight and rises with the lower pressure control ring 220. At the same time, a limit member is set on the etching body 110, and the upper pressure control ring 210 is placed on the limit member or on the upper surface of the lower pressure control ring 220. In this embodiment, Figure 2 As shown, the limiting member is set as a limiting hole 113, and accordingly, the upper control pressure ring 210 includes a perforated portion 211 and a limiting flange 212, wherein the perforated portion 211 is penetrated in the limiting hole 113, and the limiting flange 212 can selectively abut against the end of the limiting hole 113. Optionally, the limiting hole 113 can also be provided with an upper silicon ring 120. Figure 3 As shown, an energy-gathering aluminum ring 114 is disposed in the etching body 110 , and the lower surface of the lower pressure-controlling ring 220 and the upper surface of the energy-gathering aluminum ring 114 are used to form a gas channel.

[0051] During the tool movement and pressure regulation process: the driving member drives the lower pressure control ring 220 to Figure 3 The position shown in the middle a area begins to drop, and the upper control pressure ring 210 and the lower control pressure ring 220 drop together within the range of 0-2.5mm. After the drop distance is greater than 2.5mm, as shown in FIG. Figure 3As shown in the middle b area, the upper control pressure ring 210 is limited by the limit member (the limit flange 212 can abut against the end of the limit hole 113 and cannot continue to move downward) and stops descending. At this time, the driving member can also control the lower control pressure ring 220 to continue to descend 2mm, until Figure 3 The position shown in area c; that is, the descending process is caused by Figure 3 During the rising process, the driving member first drives the lower pressure control ring 220 to Figure 3 After the position shown in the middle c area starts to rise by 2 mm, the lower control pressure ring 220 and the upper control pressure ring 210 are as shown in FIG. Figure 3 The upper control pressure ring 210 is abutted as shown in the middle b area, and driven by the driving member, it drives the upper control pressure ring 210 to rise to the position as shown in the middle b area. Figure 3 The position described in area a in the figure reaches the highest position and stops, that is, the rising process is Figure 3 The process from area c to area a.

[0052] Exemplarily, the driving unit 300 further includes a cam, a rotating ring and a connecting rod 310. The rotating ring cooperates with the cam, and the connecting rod 310 is connected to both the lower pressure control ring 220 and the cam. When the driving member drives the rotating ring to rotate, the cam and the connecting rod 310 act accordingly, thereby driving the lower pressure control ring 220 to move in the up and down direction. The driving member adopts a servo motor, which is convenient for controlling the moving speed of the lower pressure control ring 220.

[0053] Furthermore, the etching device also includes an upper cover 130, and the upper silicon ring 120 is arranged at the lower end of the upper cover 130, and the upper cover 130 is buckled on the etching body 110 to form an etching cavity 111. The connecting rod 310 is passed through the upper cover 130, and the cam, rotating ring and other structures are arranged on the side of the upper cover 130 away from the etching body 110. The rotating ring is made of 410 stainless steel, which is characterized by high hardness, toughness, good corrosion resistance and not easy to rust. The hardness can reach HRC40-45 by heat treatment process, and the wear resistance is greatly increased, which ensures the transmission accuracy. Preferably, the rotating ring is processed with three evenly distributed cam grooves for cooperating with the cam to convert the rotational motion of the driving member into the lifting motion of the cam. Correspondingly, three connecting rods 310 and cams are also provided.

[0054] As an optional solution for the etching device, the detection component includes a first vacuum gauge 411 connected to the etching chamber 111, which is used to detect the vacuum degree of the etching chamber 111. At the same time, the detection component also includes a second vacuum gauge 421 connected to the etching chamber 111, which is used to detect the vacuum degree in the etching chamber 111, so that the acquired parameters are more accurate; at the same time, when one of the vacuum gauges fails, the vacuum degree in the etching chamber 111 can also be detected, which improves the reliability of the etching device during operation. A detection pipeline 420 is formed between the second vacuum gauge 421 and the etching chamber 111, and the detection pipeline 420 also includes a first switch valve 422, which is arranged between the second vacuum gauge 421 and the etching chamber 111, and is communicatively connected to the control unit, and the first switch valve 422 is used to selectively connect the second vacuum gauge 421 and the etching chamber 111.

[0055] Specifically, the etching equipment includes a dry pump 430, and a first pipeline 440 and a second pipeline 450 arranged in parallel between the dry pump 430 and the etching chamber 111, a molecular pump 441 and a second switch valve 442 located between the molecular pump 441 and the dry pump 430 are arranged on the first pipeline 440, and a third switch valve 451 is arranged on the second pipeline 450. The second switch valve 442 and the third switch valve 451 are both connected to the detection component for communication, that is, vacuuming is performed according to the vacuum degree detected by the detection component in real time. It can be understood that the second pipeline 450 is used to pre-vacuum the etching chamber 111, and the pre-vacuuming process uses the dry pump 430.

[0056] Further, when the first vacuum gauge 411 detects that the pressure of the etching chamber 111 is less than or equal to the third preset pressure (such as 10 Pa), the third switch valve 451 is closed and the second switch valve 442 is opened to end the pre-vacuuming, and vacuuming is performed simultaneously by the molecular pump 441 and the dry pump 430; when the first vacuum gauge 411 detects that the pressure of the etching chamber 111 is less than or equal to the fourth preset pressure (such as 0.5 Torr), the first switch valve 422 is opened, that is, the detection pipeline 420 is connected, and the detection pipeline 420 is vacuumed until the second vacuum gauge 421 detects that the pressure of the etching chamber 111 is the fourth preset pressure, and the third preset pressure is greater than the fourth preset pressure.

[0057] Preferably, a third vacuum gauge 452 is provided on the second pipeline 450 for detecting the vacuum degree of the second pipeline 450 in real time.

[0058] Optionally, the detection pipeline 420 further includes a first vacuum detection member 423, which is disposed between the first switch valve 422 and the etching chamber 111 and is in communication connection with the first switch valve 422. When the first vacuum detection member 423 detects that the air pressure in the etching chamber 111 is less than or equal to its maximum measured value, the first switch valve 422 opens. That is, the first switch valve 422 can only be opened when the first vacuum gauge 411 detects that the pressure in the etching chamber 111 is less than or equal to the fourth preset pressure and the first vacuum detection member 423 detects that the air pressure in the etching chamber 111 is less than or equal to its maximum measured value.

[0059] Preferably, the detection pipeline 420 also includes a second vacuum detection component 424, which is arranged between the first switch valve 422 and the etching chamber 111. The etching body 110 is provided with a transmission valve 112. The second vacuum detection component 424 is communicatively connected with the transmission valve 112. When the second vacuum detection component 424 detects that the air pressure in the etching chamber 111 is greater than its maximum measured value, the transmission valve 112 opens to discharge the gas in the etching chamber 111.

[0060] It is understandable that the etching equipment further includes a process gas supply device 500, and the process gas supply device 500 is selectively connected to the etching chamber 111 through a fourth switch valve 510, and the fourth switch valve 510 is communicatively connected to the control unit. That is, after the etching equipment and the detection pipeline 420 are evacuated, the fourth switch valve 510 is opened to introduce process gas into the etching chamber 111. After the process gas is introduced, the vacuum degree in the etching chamber 111 is detected in real time by the detection component, and the pressure control unit 200 is controlled to control the pressure so that the air pressure in the etching chamber 111 is dynamically and stably maintained at the working pressure. In addition, the control unit is controlled by a PLC system, that is, the specific function of the detection component is to detect and transmit data to the PLC system; the PLC system processes data and sends a drive signal to the drive member; the specific function of the drive member is to drive the lower pressure control ring 220 to act accordingly after receiving the PLC system signal. The data transmission, data processing and drive signal sending of the above-mentioned PLC system are all prior art and will not be elaborated here.

[0061] like Figure 5 As shown, this embodiment further discloses a pressure control method for an etching device, which is used for the etching device described in any of the above schemes, and the pressure control method comprises the following steps:

[0062] The transfer valve 112 of the etching chamber 111 is closed, and the third switch valve 451 is opened, and the etching chamber 111 is pre-evacuated through the second pipeline 450 and the dry pump 430 until the first vacuum gauge 411 detects that the pressure of the etching chamber 111 is less than or equal to the third preset pressure. It can be understood that the third preset pressure is the preset pressure of the etching chamber 111 after the pre-evacuation is completed, that is, when the pressure of the etching chamber 111 is less than or equal to the third preset pressure, the pre-evacuation operation is stopped.

[0063] The third switch valve 451 is closed and the second switch valve 442 is opened to end the pre-vacuuming, and the etching chamber 111 is further evacuated through the dry pump 430 and the molecular pump 441 of the first pipeline 440 until the first vacuum gauge 411 detects that the pressure of the etching chamber 111 is less than or equal to the fourth preset pressure.

[0064] When the first vacuum detection component 423 detects that the air pressure in the etching chamber 111 is less than or equal to its maximum measurement value, the first switch valve 422 is opened, the detection pipeline 420 is connected to the etching chamber 111, and the detection pipeline 420 and the etching chamber 111 are evacuated through the dry pump 430 and the molecular pump 441 of the first pipeline 440 until the second vacuum gauge 421 detects that the pressure in the etching chamber 111 is less than the fourth preset pressure. It can be understood that the fourth preset pressure is the preset pressure of the etching chamber 111 and the detection pipeline 420 before the process gas is introduced, that is, when the etching chamber 111 and the detection pipeline 420 are less than the fourth preset pressure, the process gas can be introduced into the etching chamber 111.

[0065] The first preset pressure, the second preset pressure and the working pressure are set; wherein the second preset pressure is adapted to the ignition pressure of the process gas. The process gas type and flow rate of the process gas supply device 500 also need to be set. It can be understood that the type of process gas affects its ignition pressure, and thus affects the setting of the second preset pressure. Therefore, by setting the type and flow rate of the process gas supply device 500, the accuracy of the second preset pressure setting can be improved, thereby ensuring that the process gas can be ignited.

[0066] The fourth switch valve 510 is opened to introduce process gas into the etching chamber 111. At this time, the second vacuum gauge 421 shows that the pressure increases, so that the etching chamber 111 reaches the first preset pressure. It can be understood that the first preset pressure is the starting pressure for the pressure control unit 200 to control the pressure at the first preset speed. When the etching chamber 111 reaches the first preset pressure, the driving member starts to drive the pressure control unit 200 to control the pressure, and the pressure control unit 200 operates at the first preset speed.

[0067] The control unit sends a pulse to make the driver drive the pressure control unit 200 to control the pressure at the first preset speed until the second preset pressure is reached in the etching chamber 111; at this time, the control unit will also control the RF unit of the etching equipment to start, so that the process gas in the etching chamber 111 is excited by electricity to produce glow discharge. It can be understood that the second preset pressure is not only the starting pressure for the pressure control unit 200 to control the pressure at the second preset speed, but also matches the starting pressure of the process gas. When the second preset pressure is reached in the etching chamber 111, the driver continues to drive the pressure control unit 200 to control the pressure, and the pressure control unit 200 moves at the second preset speed; at the same time, the process gas begins to be excited by electricity to produce glow discharge.

[0068] The control unit sends a pulse to make the driving member drive the pressure control unit 200 to control the pressure at a second preset speed, and the plasma concentration in the etching chamber 111 changes slowly until the working pressure is reached in the etching chamber 111 and the etching is stabilized at the working pressure. It can be understood that the working pressure is the pressure of the etching chamber 111 when the etching equipment is working normally. It is worth noting that at this time, the pressure control unit 200 continues to act to perform dynamic pressure control to ensure the dynamic stability of the working pressure in the etching chamber 111.

[0069] The pressure control method of the etching equipment adopts active pressure control, and the pressure control unit 200 can generate medium-density plasma by physically confining the plasma, and the pressure consistency of the wafer surface in the etching chamber 111 is better. In addition, the pressure control unit 200 confines the plasma in the pressure control unit 200, without magnetic field enhancement, low damage to the wafer, and low particle deposition on the inner wall of the etching chamber 111, which reduces the equipment etching maintenance time and improves the equipment utilization rate.

[0070] The above contents are only preferred embodiments of the present invention. For ordinary technicians in this field, according to the concept of the present invention, there will be changes in the specific implementation methods and application scopes. The content of this specification should not be understood as limiting the present invention.

Claims

1. Etching equipment, characterized in that include: An etching body (110) having an etching cavity (111) formed therein, wherein an upper silicon ring (120) is provided at an opening end of the etching body (110); The pressure control unit (200) comprises an upper pressure control ring (210) and a lower pressure control ring (220); a limiting member is arranged on the etching body (110); the upper pressure control ring (210) is placed on the limiting member or on the upper surface of the lower pressure control ring (220); a gas channel is formed at least at one place between the upper pressure control ring (210) and the upper silicon ring (120), between the upper pressure control ring (210) and the lower pressure control ring (220), and between the lower pressure control ring (220) and the etching body (110); the limiting member is arranged as a limiting hole (113); the upper pressure control ring (210) comprises a perforated portion (211) and a limiting flange (212); the perforated portion (211) is arranged in the limiting hole (113); and the limiting flange (212) can selectively abut against the end of the limiting hole (113); A driving unit (300) comprising a driving member, wherein the driving member is used to drive the lower pressure control ring (220) to move in an up-down direction to dynamically adjust the gas channel; A control unit includes a detection component, the drive member is communicatively connected to the detection component, when the detection component detects that the pressure in the etching chamber (111) is a first preset pressure, the drive member can drive the lower control pressure ring (220) to move at a first preset speed; when the detection component detects that the pressure in the etching chamber (111) is a second preset pressure, the drive member can drive the lower control pressure ring (220) to move at a second preset speed, so that the air pressure in the etching chamber (111) dynamically and stably maintains a working pressure, and the first preset speed is greater than the second preset speed.

2. The etching device according to claim 1, characterized in that: The detection assembly comprises a first vacuum gauge (411) and a second vacuum gauge (421) which are connected to the etching chamber (111); the second vacuum gauge (421) forms a detection pipeline (420); the detection pipeline (420) further comprises a first switch valve (422); the first switch valve (422) is arranged between the second vacuum gauge (421) and the etching chamber (111), and is communicatively connected to the control unit; the first switch valve (422) is used for selectively connecting the second vacuum gauge (421) and the etching chamber (111).

3. The etching device according to claim 2, characterized in that: The detection pipeline (420) further comprises a first vacuum detection component (423), which is disposed between the first switch valve (422) and the etching chamber (111) and is communicatively connected to the first switch valve (422). When the first vacuum detection component (423) detects that the air pressure in the etching chamber (111) is less than or equal to its maximum measured value, the first switch valve (422) opens.

4. The etching device according to claim 2, characterized in that: The detection pipeline (420) further comprises a second vacuum detection component (424), the second vacuum detection component (424) being arranged between the first switch valve (422) and the etching chamber (111), the etching body (110) being provided with a transmission valve (112), the second vacuum detection component (424) being communicatively connected with the transmission valve (112), and when the second vacuum detection component (424) detects that the air pressure in the etching chamber (111) is greater than its maximum measured value, the transmission valve (112) is opened.

5. The etching device according to claim 2, characterized in that: The etching device comprises a dry pump (430), and a first pipeline (440) and a second pipeline (450) which are arranged in parallel between the dry pump (430) and the etching chamber (111); the first pipeline (440) is provided with a molecular pump (441) and a second switch valve (442) located between the molecular pump (441) and the dry pump (430); the second pipeline (450) is provided with a third switch valve (451); the second switch valve (442) and the third switch valve (451) are both communicatively connected to the detection component; and the second pipeline (450) is used for pre-evacuating the etching chamber (111).

6. The etching device according to claim 5, characterized in that: When the first vacuum gauge (411) detects that the pressure of the etching chamber (111) is less than or equal to a third preset pressure, the third switch valve (451) is closed and the second switch valve (442) is opened; When the first vacuum gauge (411) detects that the pressure of the etching chamber (111) is less than or equal to a fourth preset pressure, the first switch valve (422) is opened until the second vacuum gauge (421) detects that the pressure of the etching chamber (111) is the fourth preset pressure, and the third preset pressure is greater than the fourth preset pressure.

7. The etching device according to claim 1, characterized in that: The driving unit (300) further comprises a cam, a rotating ring and a connecting rod (310), wherein the rotating ring cooperates with the cam, and the connecting rod (310) is connected to both the lower control pressure ring (220) and the cam. When the driving member drives the rotating ring to rotate, the cam and the connecting rod (310) drive the lower control pressure ring (220) to move in the up and down directions.

8. The etching device according to any one of claims 1 to 7, characterized in that: The etching equipment further comprises a process gas supply device (500), wherein the process gas supply device (500) is selectively connected to the etching chamber (111) via a fourth switch valve (510), and the fourth switch valve (510) is communicatively connected to the control unit.

9. A pressure control method for etching equipment, characterized in that: For the etching device according to any one of claims 1 to 8, the voltage control method comprises the following steps: evacuating the etching chamber (111); Setting a first preset pressure, a second preset pressure and a working pressure; Introducing a process gas into the etching chamber (111) so that the pressure in the etching chamber (111) reaches the first preset pressure; The pressure control unit (200) controls the pressure at a first preset speed until the second preset pressure is reached in the etching chamber (111); The pressure control unit (200) controls the pressure at a second preset speed until the etching chamber (111) reaches the working pressure.

10. The voltage control method of etching equipment according to claim 9, characterized in that: The step of evacuating the etching chamber (111) specifically includes: Pre-evacuating the etching chamber (111) by means of a dry pump (430); The etching chamber (111) is evacuated by using the dry pump (430) and the molecular pump (441); The detection pipeline (420) is opened, and the detection pipeline (420) and the etching chamber (111) are evacuated by using the dry pump (430) and the molecular pump (441).

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