Etching apparatus and etching system

Abstract

This invention provides an etching device and system. A rotating support module enables the crystal boat to rotate and / or asymmetrically lift and lower. Combined with the temperature difference along the height direction within the reactor, this dual-drives the etching fluid flow, enhancing fluid exchange and facilitating the timely removal of etching byproducts. A settling zone collects particulate matter. The pressure relief module employs a gradually increasing rate of pressure relief to avoid eddies within the reactor and reduce temperature disturbances caused by thermal expansion and contraction during the pressure relief process. In conjunction with a supply module and a temperature control module, a stable supercritical water etching environment is constructed, improving the uniformity and process stability of wafer etching.

Description

Technical Field

[0001] This invention relates to the field of semiconductor equipment technology, and more particularly to an etching apparatus and etching system. Background Technology

[0002] Supercritical water etching has advantages such as no surface tension, high reactivity, and no mechanical damage. It can fully wet the microstructures such as high aspect ratio micro-holes and trenches on wafers, and can achieve uniform and high-precision isotropic etching. It effectively makes up for the shortcomings of traditional dry and wet etching processes and has important application value in the field of high-end semiconductor wafer precision processing.

[0003] However, the current supercritical water etching equipment and flow control technology are not yet perfect. Due to the special working conditions of supercritical water at high temperature and high pressure, the existing driving method is difficult to achieve efficient and uniform fluid flow. The flow field distribution in the cavity is disordered and the fluid replacement rate is insufficient. The impurities generated by the etching reaction cannot be discharged in time and continue to accumulate on the surface of the microstructure. This can easily cause problems such as insufficient local etching and poor overall etching consistency, which seriously reduces the wafer processing yield and process stability, and greatly limits the application of this technology.

[0004] Therefore, it is necessary to provide a new type of etching equipment and etching system to solve the above-mentioned problems existing in the prior art. Summary of the Invention

[0005] The purpose of this invention is to provide an etching apparatus and etching system to solve the above-mentioned technical problems.

[0006] To achieve the above objectives, the etching apparatus of the present invention includes a reaction vessel, a rotary lifting module, a supply module, a temperature control module, a pressure relief module, and at least one inner extension tube. The bottom of the reaction vessel is provided with a settling zone, and the inner extension tube is connected to the pressure relief module and extends along the inner wall of the reaction vessel to the settling zone. The rotating lifting module is installed inside the reactor and is used to support the crystal boat and move the crystal boat away from the settling zone inside the reactor, as well as to drive the crystal boat to rotate and / or rise and fall. When the crystal boat is driven to rise and fall, the rising speed of the crystal boat is greater than the falling speed. The supply module is connected to the reactor and is used to supply pure water into the reactor and make the pressure inside the reactor greater than 26MPa; The temperature control module is connected to the reactor and is used to control the temperature of the reactor to make the temperature of the reactor greater than or equal to 385°C. It also creates a temperature difference along the height of the reactor so that the pure water in the reactor enters a supercritical state under the conditions of pressure greater than 26MPa and temperature greater than or equal to 385°C, forming an etching fluid. The temperature difference at different heights of the reactor drives the etching fluid to generate fluidity. The pressure relief module is connected to the reactor and is used to release pressure at a rate that gradually increases from 0 MPa / s to 0.58 MPa / s after etching is completed, so as to avoid the formation of eddies inside the reactor and reduce the temperature abnormalities caused by thermal expansion and contraction.

[0007] Optionally, the rotating support module includes a built-in bearing rotating component and a connecting component, both of which are disposed inside the reactor. The connecting component includes a cylindrical rod and a spherical head. One end of the cylindrical rod is fixed to the inner bottom of the reactor. The built-in bearing rotating component includes a support component, a first permanent magnet, and a second permanent magnet. The support component includes a base plate, a top plate, and several support rods. The top plate is used to fix to the bottom of the crystal boat. A columnar hole is opened in the middle of the base plate, through which the cylindrical rod passes. The cylindrical rod and the columnar hole are precisely fitted with a small clearance. The spherical head is threaded to the other end of the cylindrical rod to prevent the base plate from falling off the cylindrical rod. Two first mounting holes are opened on the bottom surface of the base plate with the axis of the columnar hole as the center of symmetry. The first permanent magnet and the second permanent magnet are respectively fixed in the two first mounting holes. One end of the support rod is connected to the upper surface of the base plate around the columnar hole, and the other end of the support rod is fixedly connected to the lower surface of the top plate.

[0008] Optionally, the etching equipment further includes an external stirring power module, which includes a drive motor and a main magnetic component. The drive motor is located below the reaction vessel, and the main magnetic component is connected to the rotating shaft of the drive motor. There is a gap between the main magnetic component and the reaction vessel. The main magnetic component generates an attractive force with the first permanent magnet and the second permanent magnet, respectively. When the drive motor drives the main magnetic component to rotate, the main magnetic component drives the first permanent magnet and the second permanent magnet to rotate.

[0009] Optionally, the rotating lifting module further includes a buffer spring and a third permanent magnet. The buffer spring is arranged around the cylindrical rod and located on the lower side of the base plate and is in a compressed state. A second mounting hole is opened on the lower surface of the base plate near the columnar hole, and the third permanent magnet is fixed in the second mounting hole. The external stirring power module also includes an auxiliary magnetic component, which is fixedly mounted on the drive motor housing and located on one side of the drive motor's rotating shaft. During the rotation of the first permanent magnet and the second permanent magnet by the main magnetic component, the third permanent magnet and the auxiliary magnetic component will be in the same vertical line for a certain period of time. At this time, the interaction force between the third permanent magnet and the auxiliary magnetic component is a repulsive force.

[0010] Optionally, the reactor includes a main body, a cover, a first tenon structure, and a second tenon structure. The main body has a crystal boat transfer port on its upper side. The cover is hinged to the main body. The cover can be flipped to open or close the crystal boat transfer port. The first tenon structure is arranged around the outer peripheral side wall of the cover. The second tenon structure is arranged on the main body. After the cover closes the crystal boat transfer port, the first tenon structure is rotated to make the first tenon structure and the second tenon structure engage to form an explosion-proof limiting structure.

[0011] Optionally, the main body includes an inner liner and an outer shell, both of which are spherical or ellipsoidal in shape. The inner liner is disposed inside the outer shell, and a gap is formed between the inner liner and the outer shell. The etching apparatus further includes a magnetic conductor, which is disposed within the gap and adapted to the shape of the gap. The magnetic conductor generates an attractive force with the main magnetic component, the first permanent magnet, and the second permanent magnet. The rotation of the main magnetic component drives the magnetic conductor to rotate, and the rotation of the magnetic conductor drives the first permanent magnet and the second permanent magnet to rotate.

[0012] Optionally, the main body includes an inner liner, an outer shell, and m partition supports. The inner liner and the outer shell are both spherical or ellipsoidal. The inner liner is disposed inside the outer shell, and a gap is formed between the inner liner and the outer shell. The partition supports are disposed in the gap to divide the gap into m+1 sub-gap along the height of the reactor. Each sub-gap is filled with a heat-conducting medium, where m is a natural number greater than or equal to 1. The temperature control module includes m+1 sub-temperature control units that correspond one-to-one with the sub-gap. The sub-temperature control units are disposed within the corresponding sub-gap, and each sub-temperature control unit has a different operating temperature.

[0013] Optionally, the sub-temperature control unit includes n heating elements, n temperature sensors, and n cooling elements. The heating elements are arranged at equal intervals around the axis of the liner, and a temperature sensor is provided at the midpoint between every two adjacent heating elements. The cooling elements are disposed within the gaps and on one side corresponding to the heating element, where n is a natural number greater than or equal to 2.

[0014] Optionally, the etching apparatus further includes a thermally conductive medium circulation unit with the same number of sub-gap spaces. The thermally conductive medium circulation unit includes a thermally conductive medium circulation pipe and a thermally conductive medium circulation pump. The outer casing has a thermally conductive medium circulation outlet and a thermally conductive medium circulation inlet. The two ends of the thermally conductive medium circulation pipe are respectively connected to the thermally conductive medium circulation outlet and the thermally conductive medium circulation inlet. The thermally conductive medium circulation pump is disposed on the thermally conductive medium circulation pipe. The heat transfer medium circulation outlet and the heat transfer medium circulation inlet are arranged in a centrally symmetrical manner with respect to the central axis of the outer shell. A nozzle is provided at the heat transfer medium circulation inlet, and the nozzle is arranged along the circumferential tangential direction of the outer shell, so that the heat transfer medium forms a circulation within the sub-gap.

[0015] Optionally, the main body further includes an outer explosion-proof insulation layer and an inner anti-corrosion lining layer. The outer explosion-proof insulation layer has the same shape as the outer shell and covers the outer surface of the outer shell for explosion protection and heat preservation. The anti-corrosion layer of the inner lining has the same shape as the inner lining and covers the inner surface of the inner lining. The material of the anti-corrosion layer of the inner lining is single crystal alumina or titanium alloy.

[0016] Optionally, the etching equipment further includes a rinsing and cleaning module. The rinsing and cleaning module includes an external atmospheric pressure water circulation pipe and an external water pump. One end of the external atmospheric pressure water circulation pipe is connected to the pressure relief module. The external water pump is installed on the external atmospheric pressure water circulation pipe. Pure water is supplied to the reactor through the supply module or the rinsing and cleaning pure water supply module, and then the pure water in the reactor is extracted by the external water pump to achieve rinsing and cleaning of the reactor.

[0017] Optionally, the etching equipment further includes a rinsing and cleaning module, which includes an external atmospheric pressure water circulation pipe and an external water pump. One end of the external atmospheric pressure water circulation pipe is connected to the cover and extends along the inner wall of the reactor to the settling zone. Pure water is supplied to the reactor through the supply module or the rinsing and cleaning pure water supply module, and then the pure water in the reactor is extracted by the external water pump to achieve rinsing and cleaning of the reactor.

[0018] Optionally, the rinsing and cleaning module further includes a deluge element, which is movably disposed inside the reactor and connected to the supply module or the rinsing and cleaning pure water supply module. The deluge element is used to rotate under water pressure to spray pure water into the interior of the reactor and rinse the residue on the inner wall of the reactor.

[0019] The present invention also provides an etching system, including a transport device and the etching device described in any one of the above.

[0020] The beneficial effects of this invention are as follows: the rotation and / or asymmetric lifting of the crystal boat is achieved through the rotating lifting module, combined with the temperature difference in the height direction inside the reactor, which drives the etching fluid flow in a dual manner, enhances fluid exchange, and facilitates the timely removal of etching byproducts; the settling zone can collect particulate matter, and the pressure relief module adopts a gradually increasing rate of pressure relief to avoid eddies inside the reactor and reduce temperature disturbances caused by thermal expansion and contraction during the pressure relief process; in conjunction with the supply module and temperature control module, a stable supercritical water etching environment is constructed, improving the uniformity and process stability of wafer etching. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the etching device in some embodiments of the present invention.

[0022] Figure label: 100. Main body; 101. Lining; 1011. Connecting component; 10111. Cylindrical rod; 10112. Spherical head; 102. Outer shell; 103. Heat transfer medium; 104. Partition support component; 200. Supply module; 300. Pressure relief module; 400. Inner extension tube; 500. Sub-temperature control unit; 501. Heating element; 502. Temperature sensor; 503. Cooling component; 600. External stirring power module; 601. Drive motor; 602. Main magnetic component; 700. Magnetic conduction component; 800. Built-in bearing rotating component; 801. Support component; 8011. Base plate; 80111. Columnar hole; 8012. Top plate; 8013. Support rod; 802. First permanent magnet; 900. Heat transfer medium circulation unit; 901. Heat transfer medium circulation pipe; 902. Heat transfer medium circulation pump. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions in the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without inventive effort are within the scope of protection of this invention. Unless otherwise defined, the technical or scientific terms used herein should have the ordinary meaning understood by those skilled in the art. The terms "comprising" and similar expressions used herein mean that the element or object preceding the word covers the element or object listed following the word and its equivalents, but do not exclude other elements or objects.

[0024] To address the problems existing in the prior art, embodiments of the present invention provide an etching apparatus, such as for etching dielectric materials like silicon oxide. (See reference...) Figure 1The etching equipment includes a reaction vessel, a rotary support module, a supply module 200, a temperature control module, a pressure relief module 300, and at least one inner extension tube 400.

[0025] Reference Figure 1 The reactor has a settling zone at its bottom. The inner extension pipe 400 is connected to the pressure relief module 300 and extends along the inner wall of the reactor to the settling zone. The rotating lifting module is located inside the reactor and is used to support the crystal boat and move it away from the settling zone within the reactor, as well as to rotate and / or lift the crystal boat. When lifting the crystal boat, the upward speed of the crystal boat is greater than the downward speed. The supply module 200 is connected to the reactor and is used to supply pure water to the reactor and maintain a pressure greater than 26 MPa within the reactor. The temperature control module is connected to the reactor and is used to control the temperature of the reactor. Temperature control is implemented to ensure the temperature of the reactor is greater than or equal to 385°C, and a temperature difference is created along the height of the reactor. This allows the pure water inside the reactor to enter a supercritical state under conditions of pressure greater than 26 MPa and temperature greater than or equal to 385°C, forming an etching fluid. The temperature difference at different heights of the reactor drives the etching fluid to generate fluidity. The pressure relief module 300 is connected to the reactor and is used to release pressure at a rate gradually increasing from 0 MPa / s to 0.58 MPa / s after etching is completed, in order to avoid the formation of eddies inside the reactor and reduce temperature anomalies caused by thermal expansion and contraction.

[0026] In this application, a settling zone is set at the bottom of the reactor, and an inner extension pipe is used to lead the pressure relief module to the settling zone. During the pressure relief process after etching, as the pressure decreases, the dissolving capacity of the etching fluid decreases. After the impurities precipitate, they settle to the bottom of the reactor under the action of gravity. The inner extension pipe extends the pressure relief suction end into the settling zone. During pressure relief, the etching fluid rich in precipitated impurities in the settling zone can be discharged first, reducing the retention of impurities in the reactor and preventing precipitated impurities from falling back and contaminating the wafer, effectively reducing particle defects. Moreover, the pipeline is laid along the inner wall of the reactor and will not interfere with the wafer processing station.

[0027] The rotating lifting module carries the wafer boat, elevating it away from the bottom settling area. This prevents solid residues accumulated in the settling area from directly contacting and scraping the wafer, protecting the wafer's processing surface. Simultaneously, this module enables the wafer boat to rotate and / or lift: on one hand, it drives the wafer to move synchronously, enhancing the convection exchange between the wafer surface and the supercritical etching fluid, promoting uniform etching across all processing areas of the wafer, improving the overall etching uniformity, and effectively suppressing localized under-etching or over-etching defects; on the other hand, the centrifugal force generated by the rotating wafer boat helps detach particles adhering to the wafer surface, while the lifting of the wafer boat... By setting the crystal boat's ascent speed to be greater than its descent speed in an asymmetric lifting motion, the upward pushing effect of the crystal boat on the etching fluid during the ascent process is stronger than the downward dragging effect of the fluid during the descent process. This results in the etching fluid in the central axis region of the reactor achieving a greater upward flow velocity. After reaching the upper part of the reactor, the etching fluid turns back around and flows downward along the inner wall of the reactor, forming a stable convection circulation inside the reactor that is upward in the center and downward on the wall. Furthermore, since the crystal boat is far from the settling zone inside the reactor, the disturbance of the etching fluid in the settling zone is relatively minor, causing particles to accumulate and settle in the settling zone. The combination of these two factors further promotes fluid flow.

[0028] The supply module supplies pure water to the reactor, and the temperature control module regulates the temperature inside the reactor to ensure that the pressure inside the reactor is higher than 26MPa and the temperature reaches 385℃ or above, so that the pure water is transformed into a supercritical state to form an etching fluid. In addition, the temperature control module establishes a temperature difference along the height of the reactor. The density difference caused by the temperature difference drives the supercritical etching fluid to spontaneously flow inside the reactor. Combined with the rotation and / or lifting module, the crystal boat is rotated and / or lifted, which further promotes the flow of the etching fluid, removes the etching products in time, and ensures the continuity and stability of the etching.

[0029] The pressure relief module uses a gradually increasing rate from 0MPa / s to 0.58MPa / s to complete the post-etching pressure relief, which differs from the rapid pressure relief method. This can suppress violent disturbances of the medium inside the reactor and avoid the formation of strong eddies inside the reactor. It can prevent the eddies from stirring up the solid residues already deposited in the settling area and re-spreading them to contaminate the wafer. It can also alleviate the abnormal local temperature changes inside the reactor caused by the phase change of the medium and the violent heat release due to thermal expansion and contraction during the pressure relief process. This reduces the probability of thermal stress, warping, and microcracks on the wafer caused by rapid temperature fluctuations. At the same time, it reduces the thermal shock borne by the reactor body, improves the stability of equipment operation, and ensures the wafer processing yield.

[0030] In some specific embodiments, after etching is completed, the pressure relief module increases the pressure relief rate from 0 MPa / s to 0.58 MPa / s at a constant rate over a preset time, and then maintains the pressure relief rate of 0.58 MPa / s until the gas pressure inside the reactor returns to atmospheric pressure. The preset time is 5 min to 10 min, specifically 5 min, 6 min, 7 min, 8 min, 9 min, or 10 min, or any value between any two of the aforementioned times.

[0031] Reference Figure 1 The reactor is a sealable and pressure-resistant structure, capable of withstanding pressures greater than 35 MPa and temperatures ranging from 0°C to 800°C. The reactor includes a main body 100, a cover, a first tenon structure, and a second tenon structure. A crystal boat conveying port is provided on the upper side of the main body 100. The cover is hinged to the main body 100. The cover can be flipped to open or close the crystal boat conveying port. The first tenon structure is arranged around the outer peripheral sidewall of the cover, and the second tenon structure is disposed on the main body 100. After the cover closes the crystal boat conveying port, the first tenon structure is rotated to engage with the second tenon structure, forming an explosion-proof limiting structure.

[0032] Preferably, the crystal boat transfer port is circular.

[0033] In some embodiments, the first tenon structure is configured as a locking structure that can rotate independently relative to the cover, specifically including an annular rotating member and a first mating member. The annular rotating member is movably fitted onto the outer peripheral sidewall of the cover, allowing it to rotate freely circumferentially relative to the cover. The first mating member is fixedly installed on the bottom side of the annular rotating member and extends towards the main body.

[0034] The second tenon structure is a fixed matching and locking structure, specifically including an annular fixing member and a second docking member. The annular fixing member is fixed around the periphery of the crystal boat conveying port of the main body, and the second docking member is fixedly disposed on the annular fixing member and corresponds to the position of the first docking member.

[0035] After the cover flips over to close the crystal boat transfer port, the annular rotating component is rotated so that it rotates circumferentially relative to the cover. This causes the first docking component to deflect synchronously, so that the first docking component and the second docking component form a concave-convex fit and locking docking, realizing circumferential limiting and locking between the cover and the main body. Together, they form an explosion-proof limiting structure, which can effectively counteract the force of the high pressure inside the reactor on the opening of the cover.

[0036] In some embodiments, the pressure relief module is connected to the cover.

[0037] In some embodiments, the etching apparatus further includes a pressure relief control module electrically connected to the pressure relief module. This module drives the pressure relief module to adjust the pressure relief rate based on temperature changes within the reactor. The pressure relief rate can be dynamically adjusted according to the real-time temperature of the reactor, achieving controllable pressure relief, preventing wafer damage caused by sudden temperature and pressure changes, and improving process stability. Specifically, the pressure relief module can be an electronic pressure relief valve resistant to 35 MPa, and the pressure relief control module can be a central processing unit (CPU) or a microcontroller unit (MCU). It should be noted that the supply module can be controlled by a CPU or MCU, or it can share a CPU or MCU with the pressure relief module.

[0038] In some embodiments, the pressure relief control module pre-stores a temperature-pressure relief rate relationship model. Based on this model, the pressure relief rate of the module is adjusted according to the temperature inside the reactor. The temperature-pressure relief rate relationship model can be obtained through existing simulation models or by collecting and fitting multiple sets of data.

[0039] In some embodiments, the supply module may also supply auxiliary solvents, etc., to the reactor as needed.

[0040] In some embodiments, the supply module is a commonly used pressurization device in the prior art, which will not be described in detail here.

[0041] In some embodiments, one of the inner tubes comprises two parts, one part being connected to the cover and the other part being fixed to the inner wall of the reactor. When the cover is opened, the two parts of the inner tube separate, and when the cover is closed, the two parts of the inner tube are connected together.

[0042] Reference Figure 1The rotating support module includes a built-in bearing rotating component 800 and a connecting component 1011. Both the built-in bearing rotating component 800 and the connecting component 1011 are disposed inside the reactor. The connecting component 1011 includes a cylindrical rod 10111 and a spherical head 10112. One end of the cylindrical rod 10111 is fixed to the inner bottom of the reactor. The built-in bearing rotating component 800 includes a support component 801, a first permanent magnet 802, and a second permanent magnet. The support component 801 includes a bottom plate 8011, a top plate 8012, and several support rods 8013. The top plate 8012 is used to fix to the bottom of the crystal boat. A columnar hole 80111 is opened in the middle of the bottom plate 8011, through which the cylindrical rod 10111 passes. The cylindrical rod 10111 is precisely fitted with the cylindrical hole 80111 with a small clearance. The spherical head 10112 is threaded to the other end of the cylindrical rod 10111 to prevent the base plate 8011 from falling off the cylindrical rod 10111. Two first mounting holes are opened on the bottom surface of the base plate 8011 with the axis of the cylindrical hole 80111 as the center of symmetry. The first permanent magnet 802 and the second permanent magnet are respectively fixed in the two first mounting holes. One end of the support rod 8013 is connected to the upper surface of the base plate 8011 around the cylindrical hole 80111, and the other end of the support rod 8013 is fixedly connected to the lower surface of the top plate 8012.

[0043] In some embodiments, the top plate may employ a conventional structure used in the art for supporting and securing a crystal boat.

[0044] Reference Figure 1 The etching equipment further includes an external stirring power module 600, which includes a drive motor 601 and a main magnetic component 602. The drive motor 601 is located below the reaction vessel, and the main magnetic component 602 is connected to the rotation shaft of the drive motor 601. There is a gap between the main magnetic component 602 and the reaction vessel. The main magnetic component 602 generates an attractive force with the first permanent magnet 802 and the second permanent magnet, respectively. When the drive motor 601 drives the main magnetic component 602 to rotate, the main magnetic component 602 drives the first permanent magnet 802 and the second permanent magnet to rotate.

[0045] Utilizing non-contact magnetic drive, the drive motor is located outside the reactor. Torque transmission is achieved through the magnetic attraction between the main magnetic component and the first and second permanent magnets, stably driving the internal rotating component to rotate. This, in turn, drives the crystal boat and wafer fixed on the top plate to rotate synchronously. This causes etching byproducts on the wafer to detach from the wafer surface under centrifugal force, while simultaneously agitating the etching fluid and promoting its flow. As the crystal boat continues to rotate with the internal rotating component, the wafer achieves a more uniform fluid environment inside the reactor, ensuring the etching medium acts evenly on all parts of the wafer and improving the etching uniformity. The cylindrical rod and the columnar hole in the base plate are precisely fitted with a small gap. The threaded locking ball head provides axial positioning, ensuring coaxiality during rotation and preventing the built-in rotating bearing from falling off or wobbling. This ensures smooth and reliable rotation, eliminating the need for a through-type rotating shaft at the bottom of the reactor. In high-pressure and high-temperature processes, this significantly reduces the risk of reactor explosions and shaft seal leaks. The built-in rotating bearing, supported by multiple rods, lifts the top plate and the wafer boat together, raising the wafer away from the bottom of the reactor. This keeps the wafer away from the particle settling area at the bottom of the reactor, preventing impurities and particles generated inside the reactor from re-settling and adhering to the wafer surface with the etching fluid. This effectively reduces particle contamination and improves the yield of wafer etching.

[0046] In some embodiments, the drive motor can be controlled by a central processing unit or a microcontroller, or it can share a central processing unit or microcontroller with the pressure relief module.

[0047] In some embodiments, the rotating lifting module further includes a buffer spring and a third permanent magnet. The buffer spring is arranged around the cylindrical rod and located on the lower side of the base plate, and is in a compressed state. A second mounting hole is opened on the lower surface of the base plate near the columnar hole, and the third permanent magnet is fixed in the second mounting hole. The external stirring power module further includes an auxiliary magnetic component, which is fixedly arranged on the drive motor housing and located on one side of the drive motor rotation shaft (the auxiliary magnetic component does not contact the drive motor rotation shaft). During the process of the main magnetic component driving the first permanent magnet and the second permanent magnet to rotate, the third permanent magnet and the auxiliary magnetic component will be in the same vertical line for a certain period of time. At this time, the interaction force between the third permanent magnet and the auxiliary magnetic component is a repulsive force.

[0048] The drive motor rotates the main magnetic component, causing the built-in rotating support to rotate as a whole for wafer etching. Simultaneously, the auxiliary magnetic component is fixed to the drive motor. When the third permanent magnet rotates to be directly aligned with the auxiliary magnetic component, they generate magnetic repulsion. This repulsion acts upwards on the base plate, and, in conjunction with the buffer springs arranged around the cylindrical rod, causes the entire built-in rotating support to reciprocate slightly up and down along the axis of the cylindrical rod. The crystal boat and wafer then vibrate slightly up and down. This slight up-and-down movement of the wafer disturbs the etching fluid around the wafer, disrupting the adsorption conditions for particles on the wafer surface. This allows tiny particles attached to the wafer and crystal boat to be carried away by the etching fluid, further reducing particle residue contamination. Simultaneously, it disturbs impurities diffusing upwards from the bottom settling zone of the reactor, reducing impurity adhesion to the wafer surface. To improve wafer processing yield; when the third permanent magnet and the auxiliary magnetic component are in the same vertical direction, the buffer spring assists the repulsive force between the third permanent magnet and the auxiliary magnetic component to push the built-in bearing rotating component upward. After the third permanent magnet and the auxiliary magnetic component are misaligned and the repulsive force disappears, the built-in bearing rotating component carrying the crystal boat descends under the action of gravity. The buffer spring can prevent the built-in bearing rotating component from descending rapidly, playing a buffering and shock-absorbing role, so that the rising speed of the crystal boat is greater than the falling speed. The up and down movement of the built-in bearing rotating component is entirely achieved by magnetic repulsion, without the need to add an additional independent drive source. It reuses the drive motor of the original external stirring power module, which has a simple and compact structure, does not add through moving parts inside the reactor, and does not damage the sealing of the reactor cavity. It takes into account both the functions of rotation stirring and periodic up and down vibration.

[0049] In some embodiments, the material of the buffer spring is a Ni-Cr-Al-Ti precipitation-strengthened alloy, a Cr-Mo nickel-molybdenum-chromium alloy, or a Cr-Mo-Nb nickel-based alloy, etc.

[0050] In some embodiments, the elastic force of the buffer spring is adapted to the magnetic force between the auxiliary magnetic component and the third permanent magnet. That is, when the auxiliary magnetic component and the third permanent magnet are not located in the same vertical direction, the built-in bearing rotating component of the crystal boat descends. When the auxiliary magnetic component and the third permanent magnet are located in the same vertical direction, the magnetic force between the auxiliary magnetic component and the third permanent magnet, plus the elastic force of the buffer spring, can lift the built-in bearing rotating component of the crystal boat to a certain height.

[0051] In some other embodiments, the rotating lifting module and Figure 1 The difference between the rotary lifting module described above and the one described below is that the bottom surface of the base plate does not have two first mounting holes with the axis of the columnar hole as the center of symmetry, nor does it have a first permanent magnet and a second permanent magnet, and the rotary lifting module is not rotatable. The external stirring power module and... Figure 1 The difference between the external stirring power module described above and the external stirring power module is that it does not have a main magnetic component, and the auxiliary magnetic component is fixed on the drive shaft of the drive motor and rotates with the drive motor.

[0052] Reference Figure 1 The main body 100 includes an inner liner 101 and an outer shell 102. Both the inner liner 101 and the outer shell 102 are spherical or ellipsoidal. The inner liner 101 is disposed inside the outer shell 102, and a gap is formed between the inner liner 101 and the outer shell 102. The etching device also includes a magnetic force conduction element 700. The magnetic force conduction element 700 is disposed in the gap and is adapted to the shape of the gap. The magnetic force conduction element 700 generates an attractive force with the main magnetic force element 602, the first permanent magnet 802, and the second permanent magnet. The rotation of the main magnetic force element 602 drives the magnetic force conduction element 700 to rotate, and the rotation of the magnetic force conduction element 700 drives the first permanent magnet 802 and the second permanent magnet to rotate.

[0053] The main body adopts a double-layered spherical or ellipsoidal structure with an inner liner and an outer shell. A gap is reserved between the inner liner and the outer shell, and the magnetic force transmission component is arranged inside the gap to transmit the magnetic force of the main magnetic component on the outside to the first and second permanent magnets inside the reactor. When the main magnetic component rotates, it drives the magnetic force transmission component in the gap to rotate synchronously. The magnetic force transmission component then drives the built-in bearing rotating component inside the reactor to rotate, realizing the intermediate transmission of magnetic torque. The addition of a magnetic force transmission component between the two shells can compensate for the magnetic force attenuation caused by the outer shell and inner liner shell, enhance the magnetic coupling strength between the main magnetic component and the first and second permanent magnets inside the reactor, improve the torque output of the magnetic transmission, and reduce magnetic slippage. To minimize the risk of loss of rotation, the internal rotating components are designed to have sufficient torque, ensuring more stable operation. The magnetic transmission components, with their spherical or elliptical shapes to match the gap, can be arranged to follow the gap contour without occupying the space of the internal process reaction chamber. This prevents interference with the wafer etching process environment inside the reactor and avoids contact with process fluids, wafers, or the crystal boat, thus preventing the introduction of additional particulate contaminants. Magnetic drive is entirely achieved through non-contact magnetic coupling. The outer shell and inner liner remain intact and without perforations. The reactor body has no shaft seals or through-shaft structures, completely avoiding the problems of media leakage and external impurities seeping into the chamber. This ensures a sealed process environment inside the reactor and is suitable for use with corrosive etching media.

[0054] In some embodiments, the magnetic force conduction element and the main magnetic force element can both be a single magnet, or they can adopt the same structure as the two independent magnets on the base plate, as long as they can be driven to rotate together by mutual attraction.

[0055] In some embodiments, the first permanent magnet, the second permanent magnet, and the third permanent magnet are all iron-chromium-cobalt magnets.

[0056] In some embodiments, the auxiliary magnetic component is a permanent magnet or an electromagnet.

[0057] Reference Figure 1 The main body also includes m partition support members 104. The inner liner 101 and the outer shell 102 are both spherical or ellipsoidal. The inner liner 101 is disposed inside the outer shell 102, and a gap is formed between the inner liner 101 and the outer shell 102. The partition support members 104 are disposed in the gap to divide the gap into m+1 sub-gap along the height of the reactor. Each sub-gap is filled with a heat-conducting medium 103, where m is a natural number greater than or equal to 1. The temperature control module includes m+1 sub-temperature control units 500 corresponding one-to-one with the sub-gap. The sub-temperature control units 500 are disposed in the corresponding sub-gap, and each sub-temperature control unit 500 has a different operating temperature. Taking three sub-gap units as an example, in the first sub-gap from top to bottom, the temperature of the sub-temperature control unit 500 is 400℃; in the second sub-gap from top to bottom, the temperature of the sub-temperature control unit 500 is 398℃; and in the third sub-gap from top to bottom, the temperature of the sub-temperature control unit 500 is 395℃.

[0058] To create a controllable temperature difference along the height of the reactor, m partition supports divide the gap between the outer shell and the inner liner into m+1 independent sub-gap segments along the height. These partition supports also provide support and positioning for the inner liner. Each independent sub-gap is filled with a heat-conducting medium and equipped with a corresponding sub-temperature control unit with a different operating temperature. Each sub-temperature control unit conducts heat to different height positions of the inner liner through the heat-conducting medium, thereby creating a stable and controllable temperature difference along the height of the inner liner and establishing a temperature gradient field along the height within the reactor cavity. Once a temperature difference along the height is established inside the reactor, the thermal convection motion of the etching fluid within the reactor can be actively controlled. Guiding the etching fluid within the reactor to form the desired flow pattern can suppress the disorderly upward diffusion of particles in the bottom settling zone of the reactor, reduce particle drift to the wafer surface causing contamination, improve the particle defect problem in wafer etching, and increase product yield; each sub-gap is independent of each other, reducing temperature interference between different sub-temperature control units; the heat transfer medium ensures rapid heat transfer, fast temperature control response, and high temperature control accuracy; the partition support, heat transfer medium, and sub-temperature control units are all arranged inside the gap between the outer shell and the inner liner, without extending into the process cavity of the reactor, without contacting the etching fluid, wafer, or crystal boat, without occupying the effective process space of the cavity, and without bringing additional particle contamination sources, ensuring the cleanliness of the inside of the reaction cavity.

[0059] In some embodiments, the heat-conducting medium is a heat-conducting oil, such as biphenyl-diphenyl ether heat-conducting oil.

[0060] Reference Figure 1The sub-temperature control unit 500 includes n heating elements 501, n temperature sensors 502, and n cooling elements 503. The heating elements 501 are evenly spaced around the axis of the inner liner, and a temperature sensor 502 is located at the midpoint between every two adjacent heating elements 501. The cooling elements 503 are disposed within the gaps and on one side corresponding to the heating element 501. n is a natural number greater than or equal to 2. It should be noted that... Figure 1 The sub-temperature control unit 500 described herein is not fully shown.

[0061] Each sub-gap contains n heating elements evenly spaced circumferentially along the lining axis. These elements can simultaneously output heat at multiple circumferential locations within the corresponding sub-gap. Combined with temperature sensors positioned at the midpoints of adjacent heating elements, the actual temperature at different points along the circumference of the interlayer can be collected, enabling multi-point temperature monitoring of the sub-gap's circumferential direction and avoiding detection errors caused by single-point temperature measurements. The heating elements work in conjunction with cooling components, allowing for bidirectional heating and cooling control within the same sub-gap. Combined with real-time feedback from the multi-point temperature sensors, the temperature at various points along the circumference of the sub-gap can be evenly adjusted, effectively eliminating circumferential temperature deviations in the lining and ensuring a uniform temperature along the circumference at the same height within the lining, preventing temperature discrepancies at the same height within the reactor. To prevent localized overheating or undercooling, the system ensures temperature uniformity within the same height layer. The heating element, temperature sensor, and cooling components are all located within the interlayer gap between the outer shell and inner liner, preventing them from entering the reactor process chamber, contacting etching fluids, wafers, and the crystal boat, thus avoiding the introduction of impurity particles into the reactor and maintaining a clean environment within the reactor. With n≥2, a distributed layout of multiple heating elements, sensors, and cooling components is adopted. Compared to a single set of temperature control devices, this provides higher redundancy. If a heating element or cooling component malfunctions, the remaining components can still participate in temperature control, reducing the impact of single-point failures on the process temperature field and improving equipment process stability.

[0062] In some embodiments, the heating element includes a heating wire or a heating rod, etc.

[0063] In some embodiments, the cooling element is a semiconductor refrigeration chip or a cooling water pipe.

[0064] In some embodiments, the pressure relief control module may obtain the temperature inside the reactor from the temperature sensors, for example, by taking the average of the temperatures obtained by all the temperature sensors as the temperature inside the reactor.

[0065] In some embodiments, the sub-temperature control unit further includes a sub-gap temperature control unit, which is electrically connected to the corresponding heating element, the corresponding temperature sensor, and the corresponding cooling element. The sub-gap temperature control unit adjusts the power of the heating element and the cooling element located between the two temperature sensors based on the temperature detected by two adjacent temperature sensors. The sub-gap temperature control unit can be a central processing unit or a microcontroller, or it can share a central processing unit or microcontroller with the pressure relief module. The sub-gap temperature control unit has a pre-stored temperature-power model, and adjusts the power of the corresponding heating element and the cooling element based on this model. The temperature-power model can be obtained through simulation or by fitting multiple sets of collected data.

[0066] Reference Figure 1 The etching equipment further includes a thermally conductive medium circulation unit 900, the same number as the number of sub-gap units. Each thermally conductive medium circulation unit 900 includes a thermally conductive medium circulation pipe 901 and a thermally conductive medium circulation pump 902. The outer casing has a thermally conductive medium circulation outlet and a thermally conductive medium circulation inlet. The two ends of the thermally conductive medium circulation pipe 901 are respectively connected to the thermally conductive medium circulation outlet and the thermally conductive medium circulation inlet. The thermally conductive medium circulation pump 902 is mounted on the thermally conductive medium circulation pipe 901. The thermally conductive medium circulation outlet and the thermally conductive medium circulation inlet are arranged symmetrically about the central axis of the outer casing. A nozzle is provided at the thermally conductive medium circulation inlet, and the nozzle is arranged along the circumferential tangential direction of the outer casing, so that the thermally conductive medium 103 forms a circulating flow within the sub-gap. It should be noted that... Figure 1 The heat-conducting medium circulation unit 900 described herein is not fully shown.

[0067] Each sub-gap is equipped with an independent heat transfer medium circulation unit, driven by a heat transfer medium circulation pump to circulate the heat transfer medium within the sub-gap, accelerating heat exchange within the interlayer and improving temperature control response speed. The heat transfer medium circulation inlet and outlet are centrally symmetrically arranged, and the tangential nozzle at the inlet creates circulation of the heat transfer medium within the sub-gap, promoting sufficient flow of the heat transfer medium within the sub-gap, eliminating local stagnation areas, and resulting in a more uniform temperature distribution within the same sub-gap. In conjunction with the sub-temperature control unit, heat can be quickly and evenly transferred to the outer wall of the liner, ensuring the circumferential temperature consistency of the liner at the corresponding height layer and not disrupting the height-direction temperature gradient between each sub-gap. The circulation pipeline and pump body are all located on the outside of the outer shell, with only the nozzle located in the interlayer gap, not intruding into the process cavity and not causing contamination to the internal wafer processing environment.

[0068] In some embodiments, the main body further includes an outer explosion-proof insulation layer and an inner anti-corrosion lining layer. The outer explosion-proof insulation layer has the same shape as the outer shell and covers the outer surface of the outer shell, serving as explosion-proof and heat-insulating. The inner anti-corrosion lining layer has the same shape as the inner lining and covers the inner surface of the inner lining. The material of the inner anti-corrosion lining layer is single-crystal alumina or titanium alloy. The outer explosion-proof insulation layer comprises an inner nano-aerogel felt insulation core, a middle stainless steel wire buffer mesh layer, and an outer 316L stainless steel protective shell.

[0069] In some embodiments, the etching apparatus further includes a rinsing and cleaning module, which includes an external atmospheric pressure water circulation pipe and an external water pump. One end of the external atmospheric pressure water circulation pipe is connected to the pressure relief module, and the external water pump is installed on the external atmospheric pressure water circulation pipe. Pure water is supplied to the reactor through the supply module or the rinsing and cleaning pure water supply module, and then the pure water in the reactor is extracted by the external water pump to achieve rinsing and cleaning of the reactor.

[0070] In some other embodiments, the etching equipment further includes a rinsing and cleaning module, which includes an external atmospheric pressure water circulation pipe and an external water pump. One end of the external atmospheric pressure water circulation pipe is connected to the cover and extends along the inner wall of the reactor to the settling zone (extending to the bottom of the settling zone). Pure water is supplied to the reactor through the supply module or the rinsing and cleaning pure water supply module, and then the pure water in the reactor is extracted by the external water pump to achieve rinsing and cleaning of the reactor.

[0071] In some embodiments, the flushing and cleaning pure water supply module has the same structure as the supply module and is connected to the cover.

[0072] In some embodiments, the rinsing and cleaning module further includes a deluge element movably disposed within the reactor and connected to the supply module or the rinsing and cleaning pure water supply module. This deluge element rotates under water pressure to spray pure water into the interior of the reactor, rinsing away residues on the inner wall of the reactor. Specifically, the deluge element is a self-driven rotating nozzle.

[0073] The present invention also provides an etching system, including a transport device and the etching device. The transport device is a commonly used crystal boat transport device in the art, and its specific structure, composition and working principle are well known to those skilled in the art, so it will not be described in detail here.

[0074] While embodiments of the present invention have been described in detail above, it will be apparent to those skilled in the art that various modifications and variations can be made to these embodiments. However, it should be understood that such modifications and variations fall within the scope and spirit of the invention as set forth in the claims. Furthermore, the invention described herein may have other embodiments and can be implemented or carried out in various ways.

Claims

1. An etching apparatus, characterized in that, It includes a reaction vessel, a rotary lifting module, a supply module, a temperature control module, a pressure relief module, and at least one inner extension pipe. The bottom of the reaction vessel is provided with a settling zone, and the inner extension pipe is connected to the pressure relief module and extends along the inner wall of the reaction vessel to the settling zone. The rotating lifting module is installed inside the reactor and is used to support the crystal boat and move the crystal boat away from the settling zone inside the reactor, as well as to drive the crystal boat to rotate and / or rise and fall. When the crystal boat is driven to rise and fall, the rising speed of the crystal boat is greater than the falling speed. The supply module is connected to the reactor and is used to supply pure water into the reactor and make the pressure inside the reactor greater than 26MPa; The temperature control module is connected to the reactor and is used to control the temperature of the reactor to make the temperature of the reactor greater than or equal to 385°C. It also creates a temperature difference along the height of the reactor so that the pure water in the reactor enters a supercritical state under the conditions of pressure greater than 26MPa and temperature greater than or equal to 385°C, forming an etching fluid. The temperature difference at different heights of the reactor drives the etching fluid to generate fluidity. The pressure relief module is connected to the reactor and is used to release pressure at a rate that gradually increases from 0 MPa / s to 0.58 MPa / s after etching is completed, so as to avoid the formation of eddies inside the reactor and reduce the temperature abnormalities caused by thermal expansion and contraction.

2. The etching apparatus according to claim 1, characterized in that, The rotating support module includes a built-in bearing rotating component and a connecting component, both of which are disposed inside the reactor. The connecting component includes a cylindrical rod and a spherical head. One end of the cylindrical rod is fixed to the inner bottom of the reactor. The built-in bearing rotating component includes a support component, a first permanent magnet, and a second permanent magnet. The support component includes a base plate, a top plate, and several support rods. The top plate is used to fix the bottom of the crystal boat. A columnar hole is opened in the middle of the base plate, through which the cylindrical rod passes. The cylindrical rod and the columnar hole are precisely fitted with a small clearance. The spherical head is threaded to the other end of the cylindrical rod to prevent the base plate from falling off the cylindrical rod. Two first mounting holes are opened on the bottom surface of the base plate with the axis of the columnar hole as the center of symmetry. The first permanent magnet and the second permanent magnet are respectively fixed in the two first mounting holes. One end of the support rod is connected to the upper surface of the base plate around the columnar hole, and the other end of the support rod is fixedly connected to the lower surface of the top plate.

3. The etching apparatus according to claim 2, characterized in that, It also includes an external stirring power module, which includes a drive motor and a main magnetic component. The drive motor is located below the reactor, and the main magnetic component is connected to the rotating shaft of the drive motor. There is a gap between the main magnetic component and the reactor. The main magnetic component generates an attractive force with the first permanent magnet and the second permanent magnet respectively. When the drive motor drives the main magnetic component to rotate, the main magnetic component drives the first permanent magnet and the second permanent magnet to rotate.

4. The etching apparatus according to claim 3, characterized in that, The rotating lifting module also includes a buffer spring and a third permanent magnet. The buffer spring is arranged around the cylindrical rod and located on the lower side of the base plate and is in a compressed state. A second mounting hole is opened on the lower surface of the base plate near the columnar hole, and the third permanent magnet is fixed in the second mounting hole. The external stirring power module also includes an auxiliary magnetic component, which is fixedly mounted on the drive motor housing and located on one side of the drive motor's rotating shaft. During the rotation of the first permanent magnet and the second permanent magnet by the main magnetic component, the third permanent magnet and the auxiliary magnetic component will be in the same vertical line for a certain period of time. At this time, the interaction force between the third permanent magnet and the auxiliary magnetic component is a repulsive force.

5. The etching apparatus according to claim 3, characterized in that, The reactor includes a main body, which includes an inner liner and an outer shell. Both the inner liner and the outer shell are spherical or ellipsoidal. The inner liner is disposed inside the outer shell, and a gap is formed between the inner liner and the outer shell. The etching apparatus further includes a magnetic conductor, which is disposed within the gap and adapted to the shape of the gap. The magnetic conductor generates an attractive force with the main magnetic component, the first permanent magnet, and the second permanent magnet. The rotation of the main magnetic component drives the magnetic conductor to rotate, and the rotation of the magnetic conductor drives the first permanent magnet and the second permanent magnet to rotate.

6. The etching apparatus according to claim 1, characterized in that, The reactor includes a main body, which includes an inner liner, an outer shell, and m partition supports. The inner liner and the outer shell are both spherical or ellipsoidal. The inner liner is disposed inside the outer shell, and a gap is formed between the inner liner and the outer shell. The partition supports are disposed within the gap to divide the gap into m+1 sub-gap along the height of the reactor. Each sub-gap is filled with a heat-conducting medium, where m is a natural number greater than or equal to 1. The temperature control module includes m+1 sub-temperature control units that correspond one-to-one with the sub-gap. The sub-temperature control units are disposed within the corresponding sub-gap, and each sub-temperature control unit has a different operating temperature.

7. The etching apparatus according to claim 6, characterized in that, The sub-temperature control unit includes n heating elements, n temperature sensors, and n cooling components. The heating elements are arranged at equal intervals around the axis of the inner liner, and a temperature sensor is set at the midpoint between every two adjacent heating elements. The cooling components are set in the gaps and on one side of the corresponding heating element. n is a natural number greater than or equal to 2.

8. The etching apparatus according to claim 6 or 7, characterized in that, The etching equipment also includes a thermally conductive medium circulation unit with the same number of sub-gap spaces. The thermally conductive medium circulation unit includes a thermally conductive medium circulation pipe and a thermally conductive medium circulation pump. The outer casing has a thermally conductive medium circulation outlet and a thermally conductive medium circulation inlet. The two ends of the thermally conductive medium circulation pipe are respectively connected to the thermally conductive medium circulation outlet and the thermally conductive medium circulation inlet. The thermally conductive medium circulation pump is installed on the thermally conductive medium circulation pipe. The heat transfer medium circulation outlet and the heat transfer medium circulation inlet are arranged in a centrally symmetrical manner with respect to the central axis of the outer shell. A nozzle is provided at the heat transfer medium circulation inlet, and the nozzle is arranged along the circumferential tangential direction of the outer shell, so that the heat transfer medium forms a circulation within the sub-gap.

9. The etching apparatus according to claim 6 or 7, characterized in that, The main body also includes an outer explosion-proof insulation layer and an inner anti-corrosion lining layer. The outer explosion-proof insulation layer has the same shape as the outer shell and covers the outer surface of the outer shell, and is used for explosion protection and heat preservation. The anti-corrosion layer of the inner lining has the same shape as the inner lining and covers the inner surface of the inner lining. The material of the anti-corrosion layer of the inner lining is single crystal alumina or titanium alloy.

10. The etching apparatus according to claim 1, characterized in that, The reactor includes a main body, a cover, a first tenon structure, and a second tenon structure. A crystal boat conveying port is provided on the upper side of the main body. The cover is hinged to the main body. The cover can be flipped to open or close the crystal boat conveying port. The first tenon structure is arranged around the outer peripheral side wall of the cover. The second tenon structure is arranged on the main body. After the cover closes the crystal boat conveying port, the first tenon structure is rotated to make the first tenon structure and the second tenon structure engage to form an explosion-proof limiting structure.

11. The etching apparatus according to claim 1, characterized in that, The etching equipment also includes a rinsing and cleaning module, which includes an external atmospheric pressure water circulation pipe and an external water pump. One end of the external atmospheric pressure water circulation pipe is connected to the pressure relief module, and the external water pump is installed on the external atmospheric pressure water circulation pipe. Pure water is supplied to the reactor through the supply module or the rinsing and cleaning pure water supply module, and then the pure water in the reactor is pumped out by the external water pump to achieve rinsing and cleaning of the reactor. or, The etching equipment also includes a rinsing and cleaning module, which includes an external atmospheric pressure water circulation pipe and an external water pump. The reactor includes a cover, one end of which is connected to the cover and extends along the inner wall of the reactor to the settling zone. Pure water is supplied to the reactor through the supply module or the rinsing and cleaning pure water supply module, and then the pure water in the reactor is pumped out by the external water pump to achieve rinsing and cleaning of the reactor.

12. The etching apparatus according to claim 11, characterized in that, The rinsing and cleaning module also includes a deluge element, which is movably disposed inside the reactor and connected to the supply module or the rinsing and cleaning pure water supply module. It is used to rotate under water pressure to spray pure water into the interior of the reactor and rinse the residue on the inner wall of the reactor.

13. An etching system, characterized in that, It includes a conveying device and an etching device as described in any one of claims 1-12.

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