A quartz crucible with a non-rectangular or non-circular cross-section for pulling a rectangular single-crystal silicon and a method for growing a rectangular single-crystal silicon ingot by the Czochralski method

Abstract

The present invention relates to the technical field of silicon single crystal preparation, and provides a quartz crucible with a non-rectangular or non-circular cross-section for pulling rectangular silicon single crystals and a method for growing rectangular silicon single crystal ingots by the Czochralski method. On the inner surface of the quartz crucible within a range of 2×42° that is symmetric about the line connecting the top of the convex portion and the center of symmetry of the pattern, 4u or 2n + 2m blades protruding relative to the inner surface of the quartz crucible are arranged to rotate around the z-axis. The angle between the blade and the xy plane, that is, the suppression angle α1, satisfies 10 ≤ α1 ≤ 80°; on the bottom surface of the inner cavity of the quartz crucible, one or more rotors protruding relative to the bottom surface of the inner cavity of the quartz crucible are arranged. A point P on the contour line of the rotor has a cutting-in angle, and the range of the cutting-in angle is 2° < α2 < 80°; thereby achieving the suppression of the liquid silicon flow and reducing the oxygen content.

Description

Technical Field

[0001] The present invention relates to the technical field of silicon single crystal preparation, and particularly relates to a quartz crucible with a non-rectangular or non-circular cross-section for pulling rectangular silicon single crystals and a method for growing rectangular silicon single crystal ingots by the Czochralski method. Background Art

[0002] The patent with the application number 202410993158.7 discloses a method for growing rectangular silicon single crystal ingots by the Czochralski method, which has the advantages of simple process, high production efficiency, large cross-sectional area of the crystal bar, etc. However, in terms of controlling the content of crystal oxygen elements, the internal stress of the silicon single crystal bar, and the uniformity of the radial impurity distribution, there are the following deficiencies:

[0003] First, since the crystal and the crucible stop rotating when pulling rectangular silicon single crystals compared with pulling cylindrical silicon single crystals, the natural thermal convection of the liquid silicon lacks restraint, and the thermal convection of the liquid silicon is relatively strong. Therefore, the erosion of the crucible wall by the thermal convection of the liquid silicon causes more oxygen elements in the quartz crucible to enter the liquid silicon, resulting in a higher impurity oxygen content in the silicon single crystal. And due to the change in the height of the liquid silicon surface during the crystal pulling process affecting the intensity of the thermal convection of the liquid silicon, and the segregation coefficient of impurity oxygen greater than 1, the longitudinal distribution of impurity oxygen in the entire silicon single crystal ingot is uneven, generally showing a higher impurity oxygen concentration at the head.

[0004] Second, when growing rectangular silicon single crystals, there is only thermal convection of the liquid silicon without crystal rotation and crucible rotation. Then, the heat dissipation condition at the center of the crystal growth interface is worse than that of pulling cylindrical silicon single crystals, and the temperature of the liquid silicon at the center is higher, making the crystal growth interface concave. The concave crystal surface will generate a higher internal stress in the silicon single crystal and silicon wafers. The excessive internal stress in the crystal will destroy the growth environment of the silicon single crystal and is a limiting factor for the maximum cross-sectional area of the silicon single crystal bar. The concave crystal surface increases the internal stress on the plane of the cut silicon wafers and makes the impurity distribution in the wafers uneven.

[0005] Third, the existing technical measures for controlling the oxygen content and its distribution uniformity of Czochralski silicon single crystals include two categories: magnetic field oxygen control and non-magnetic field oxygen control. The former places the silicon melt in a certain magnetic field environment and forms a damping force on the thermal convection movement of the liquid silicon by means of the Lorentz force to achieve the purpose of oxygen control. This measure is effective in oxygen control but has high equipment and operating costs. The latter controls oxygen by adopting appropriate thermal field distribution, crucible position, crucible rotation, crystal rotation and other process means, with lower costs. However, when pulling rectangular silicon single crystals, the lack of coordination of crystal rotation and crucible rotation makes it difficult to control the flow field in the crucible.

[0006] Fourth, when pulling silicon single crystal ingots with a rectangular cross-section, since the distances from the highest points of the four protruding parts in the horizontal cross-section of the crucible to the z-axis are different, it is not conducive to the rotation of the crucible around the z-axis in the middle of the heater.

[0007] The present invention is proposed to solve at least one of the above problems. It should be noted that some content of the present invention only provides background art related to the present invention, and does not necessarily constitute prior art or well-known art. Summary of the Invention

[0008] I. Nouns and Terms:

[0009] For the convenience of description, the following nouns and terms are defined in this application document:

[0010] 1) Blade suppression angle :

[0011] The angle between the tangent of a point P on the projection line of the blade contour line on the top surface of the convex part inside the inner cavity of the quartz crucible in the xz plane and the xy plane. It can be understood that: when the projection line of the blade contour line in the xz plane is a curve, the tangent line is the tangent line at point P of the blade contour line; when it is a straight line, its tangent line is equivalent to the slope of the blade contour line.

[0012] 2) Inlet angle of the rotor :

[0013] The angle (acute angle) between a point Q on the projection of the rotor contour line on the bottom inner wall of the quartz crucible in the xy plane and the tangent line of the circle O at point Q. The circle O is in the xy plane, the center of the circle O is on the z-axis, and the radius is the distance between point Q and the z-axis .

[0014] 3) "Right-handed" and "left-handed" of the quartz crucible:

[0015] Close the four fingers of the right hand, with the thumb pointing downward, in the direction of the bottom of the crucible (-z direction), and the rotation direction of the four fingers represents the rotation direction Ω of the crucible, then this is the "right-handed" of the crucible; similarly, close the four fingers of the left hand, with the thumb pointing downward, in the direction of the bottom of the crucible (-z direction), then the rotation direction of the four fingers represents the rotation direction Ω of the crucible, and this is the "left-handed" of the crucible.

[0016] 4) "Right-handed" and "left-handed" of the blade:

[0017] For the blade located on the inner side wall of the top of the convex part of the quartz crucible: close the four fingers of the right hand, with the thumb pointing downward, in the direction of the bottom of the crucible (-z direction), and the rotation direction of the four fingers represents the downward-slanting direction of the blade contour line, then this is regarded as the "right-handed" of the blade; similarly, close the four fingers of the left hand, with the thumb pointing downward, in the direction of the bottom of the crucible (-z direction), and the rotation direction of the four fingers represents the downward-slanting direction of the blade rotation, then this is regarded as the "left-handed" of the rotor.

[0018] 5) "Right-handed" and "left-handed" of the rotor:

[0019] Rotary vane at the inner bottom of the quartz crucible: With the four fingers of the right hand closed and the thumb pointing downward towards the bottom of the crucible (-z direction), the rotation direction of the four fingers represents the direction in which the rotary vane contracts and rotates towards the crucible rotation axis, and this is regarded as the "right rotation" of the bottom rotary vane; similarly, with the four fingers of the left hand closed and the thumb pointing downward towards the bottom of the crucible (-z direction), the rotation direction of the four fingers represents the direction in which the rotary vane contracts and rotates towards the crucible rotation axis, and this is regarded as the "left rotation" of the bottom rotary vane.

[0020] 6) Quasi-circle: In this application document, it refers to a figure close to a circle.

[0021] 7) Transverse diameter: In this application document, it refers to the distance between two intersection points where a straight line passing through the symmetry center of the crucible cross-section intersects two opposite edge points of the crucible.

[0022] 8) "Large transverse diameter" and "small transverse diameter" inside the quartz crucible:

[0023] The "large transverse diameter" of the quartz crucible refers to two longest equal-length transverse diameters that coincide with the symmetry axis of the horizontal cross-section and are perpendicular to each other; or it refers to one longest transverse diameter that coincides with the symmetry axis of the horizontal cross-section and one sub-longest transverse diameter perpendicular to it; the "small transverse diameter" of the quartz crucible refers to the shortest transverse diameter within the horizontal cross-section of the quartz crucible. It can be understood that: A quartz crucible with two equal-length transverse diameters is used for pulling silicon single crystals with a regular cross-section; a quartz crucible with one longest transverse diameter and one sub-longest transverse diameter is used for pulling silicon single crystals with a long-shaped cross-section.

[0024] 7) The first "boundary layer" and the first "outer boundary layer" of liquid silicon at the liquid silicon / crucible interface:

[0025] The first "boundary layer" of liquid silicon is a flowing thin layer in the liquid silicon fluid that adheres to the inner surface of the top of the protruding part of the crucible and where the viscous force cannot be ignored. For the laminar flow case, the thickness of the first boundary layer is a function of the crucible wall position (such as the liquid level height z), and has the following relationship:

[0026]

[0027] Where:

[0028] : Viscosity coefficient of liquid silicon;

[0029] (z): Characteristic length, the length of the laminar flow of the thermally convective liquid silicon adhering to the crucible wall;

[0030] : Density of liquid silicon;

[0031] (z): The liquid silicon thermal convection flow rate of the first outer boundary layer of liquid silicon at the blade;

[0032] 、 (z), etc. can be obtained by simulating the internal flow field of liquid silicon through simulation software such as CG-sim and FEMAG, or can also be obtained through experiments. Here, only the corresponding regional rate in the liquid silicon fluid is given as an example. Since the rate in the existing liquid silicon fluid can be obtained by various methods such as simulation and theoretical calculation, the specific obtaining method is not specifically limited herein.

[0033] The first "outer boundary layer" of liquid silicon refers to a thin layer outside the adjacent first "boundary layer", where the thermal convection rate of liquid silicon can reach more than 90% of the highest flow rate in the vicinity.

[0034] 8) The second "boundary layer" and the second "outer boundary layer" of liquid silicon at the liquid silicon / crucible interface:

[0035] Similar to the first "boundary layer" of liquid silicon, the second "boundary layer" of liquid silicon is a thin flowing layer in the liquid silicon fluid where the viscous force close to the bottom surface of the inner cavity of the crucible cannot be ignored. In this application document, the thickness of the second boundary layer is a function of the position of the crucible wall (such as the distance r from the axis). For the laminar flow situation, there is the following relationship:

[0036]

[0037] Among them:

[0038] : The viscosity coefficient of liquid silicon;

[0039] (r): The characteristic length, the length of the laminar flow of the convective liquid silicon against the crucible wall;

[0040] : The density of liquid silicon;

[0041] (r): The convective rate of liquid silicon in the second outer boundary layer of liquid silicon at the rotor at the place of interest (such as a point P on the contour line of any rotor).

[0042] (r), can be obtained by simulating the internal flow field of liquid silicon through simulation software such as CG-sim and FEIMAG, or can also be obtained through experiments. Here, only the corresponding regional rate in the liquid silicon fluid is given as an example. Since the rate in the existing liquid silicon fluid can be obtained by various methods such as simulation and theoretical calculation, the specific obtaining method is not specifically limited herein.

[0043] Similarly, the second "outer boundary layer" refers to a thin layer outside the adjacent second "boundary layer", where the thermal convection rate of liquid silicon can reach more than 90% of the highest flow rate in the vicinity.

[0044] The above boundary layer can also be defined by the concentration of impurity oxygen contained in the layer. Assume that there is an excess oxygen impurity concentration in the boundary layer that exceeds the average oxygen ion impurity concentration level of the liquid silicon inside the crucible. The excess oxygen impurity concentration at the crucible wall is . Starting from the crucible wall, up to the point where the excess oxygen impurity concentration in the liquid silicon drops to 0.37 . It has been proven that the boundary layer thickness defined by the above two methods is quite comparable.

[0045] 9) The third "boundary layer" and the third "outer boundary layer":

[0046] The third "boundary layer" is the liquid silicon / silicon single crystal boundary layer, referring to a thin layer of liquid silicon adjacent to the silicon single crystal. The most prominent feature of this thin layer is the existence of a difference from the average impurity concentration level of the liquid silicon inside the crucible. Assume that there is an excess impurity concentration in the third boundary layer that exceeds the average impurity concentration level of the liquid silicon inside the crucible . For impurities with a solid-liquid segregation coefficient of silicon less than 1, such as phosphorus, arsenic, and antimony, is positive. For impurities with a solid-liquid segregation coefficient of silicon greater than 1, such as oxygen, is negative. The excess impurity concentration at the crystal silicon crystallization interface is .

[0047] Define a thin layer starting from the crystal silicon solid-liquid interface up to the point where the excess impurity concentration in the liquid silicon drops to 0.37 as the third boundary layer.

[0048] The thickness of the third boundary layer can also be calculated by the following formula:

[0049]

[0050] where:

[0051] : correlation coefficient. For example, for the impurity antimony, 1.61 can be selected;

[0052] D: diffusion coefficient of the impurity of concern in liquid silicon;

[0053] : kinematic viscosity coefficient of liquid silicon;

[0054] : relative movement rate of the liquid silicon in the third "outer boundary layer".

[0055] 、 It can be obtained by simulating the internal flow field of liquid silicon through simulation software such as CG-sim and FEIMAG, or it can also be obtained through experiments. Here, only the speed of the corresponding area in the liquid silicon flow is given as an example. Since the speed in the existing liquid silicon flow can be obtained by various methods such as simulation and theoretical calculation, the specific method of obtaining it is not specifically limited here.

[0056] The third "outer boundary layer" refers to a liquid silicon layer adjacent to the third boundary layer, and the third outer boundary layer has the highest liquid silicon flow rate in its vicinity.

[0057] 10) Front angle β of the (rib):

[0058] Take the cross-section of the rib perpendicular to the length direction of the rib. The angle between the line of the surface that pushes the liquid silicon to move and the line segment between the two endpoints of its bottom surface is defined as the front angle β of the (rib).

[0059] 11) Rear angle γ of the (rib):

[0060] Take the cross-section of the rib perpendicular to the length direction of the rib. The angle between the line that deviates from the movement direction of the rib and the line segment between the two endpoints of its bottom surface is defined as the rear angle γ of the (rib).

[0061] II. Invention purpose and invention content:

[0062] In the prior art, pulling a silicon single crystal with a rectangular cross-section requires the orientation of the silicon single crystal relative to the crucible to be fixed. Therefore, first, the degree of freedom of crystal rotation is restricted; second, the rotation of the crucible will cause distortion of the internal heat distribution and flow field distribution in the crucible. The asymmetric heat field and flow field distributions damage the growth environment of the silicon single crystal with a rectangular cross-section. Therefore, the degree of freedom of crucible rotation is also restricted.

[0063] However, as is well known, in the prior art of magnetic field-free crystal pulling technology, crucible rotation and crystal rotation are essential for balancing the thermal buoyancy convection of liquid silicon, and balancing the thermal buoyancy of liquid silicon is an essential means for reducing and controlling the impurity oxygen content in the silicon single crystal.

[0064] The purpose of the present invention is to achieve at least one of the following objectives:

[0065] 1) Introduce a quartz crucible and crucible rotation process technology with the function of suppressing the thermal convection of liquid silicon, and introduce a crystal rotation that can cancel the crucible rotation in the same direction and at the same speed, so as to solve the problem of lack of reverse crystal rotation and insufficient suppression of the thermal convection of liquid silicon when pulling a silicon single crystal with a rectangular cross-section in the prior art, and achieve an equal or better balance effect on the thermal convection intensity of liquid silicon compared with the prior art, and reduce the oxygen impurity in the silicon single crystal;

[0066] 2) Further, make the oxygen content in the crystal controllable during the crystal pulling process;

[0067] 3) Reduce the interference to the small environment of the impurity distribution at the crystallization interface of the silicon single crystal, so as to increase the effective solid-liquid segregation coefficient of n-type impurities and reduce the effective solid-liquid segregation coefficient of impurity oxygen.

[0068] The beneficial effects of the present invention are as follows:

[0069] First, by means of the quartz crucible of the present invention and the provided process method, a silicon single crystal ingot with a rectangular cross-section and controllable oxygen content and its distribution can be drawn;

[0070] Second, reduce the longitudinal concentration gradient of the n-type impurity distribution in the silicon single crystal ingot, draw a longer and heavier silicon single crystal, and improve the production efficiency;

[0071] Third, improve the flatness of the crystallization plane of the silicon single crystal rod and reduce the mechanical stress and impurity concentration distribution stress of the silicon single crystal ingot.

[0072] The content of the present invention includes:

[0073] In the first aspect, the present invention provides a quartz crucible with a non-rectangular or non-circular cross-section for drawing a rectangular silicon single crystal. The inner cavity pattern of its cross-section in the xy plane has four outwardly protruding portions. On the inner surface of the quartz crucible within a range of not more than 2×42° that is symmetric about the left and right of the connection line between the top of the protruding portion and the symmetry center of the pattern, 4u or 2n + 2m blades protruding relative to the inner surface of the quartz crucible are arranged in a rotation around the z-axis. Among them, u, n, and m are integers greater than or equal to 1. On the inner surface of the quartz crucible at the top of one of the four outwardly protruding portions, u, n, or m blades are arranged. The angle between the blade and the xy plane, that is, the inhibition angle , , and the rotation direction of the protruding blade is opposite to the rotation direction of the quartz crucible.

[0074] The principle of oxygen reduction and control is that the main source of oxygen impurities in liquid silicon is the crucible wall of the quartz crucible close to the heater, especially the high-temperature area of the crucible closest to the heater. The buoyancy of the thermal convection of liquid silicon caused by high temperature is several to dozens of times that of other forces (such as the inertial centrifugal force generated by crucible rotation and crystal rotation, the surface tension of liquid silicon, the blowing and shearing force of argon, the advection force of liquid silicon caused by crystallization, etc.). Under the action of buoyancy, the high-speed rising liquid silicon flow corrodes the crucible wall and brings the oxygen in it into the liquid silicon and then into the silicon single crystal ingot.

[0075] The rising liquid silicon flow is affected by the inhibition angle Blocked by the blades, its speed can be decomposed into two components: longitudinally upward and tangential to the crucible wall with the opposite rotation direction of the blades. At this time, if the crucible rotates in the direction opposite to the rotation direction of the blades, the blades will produce a pressing effect on the liquid silicon, and the pressing speed component cancels out the two speed components of the liquid silicon, achieving the purpose of suppressing the liquid silicon from rising along the crucible wall under the action of buoyancy and maintaining the stability of the liquid silicon, which is beneficial for the crucible rotation to balance the two speed components of longitudinally upward and tangential to the crucible wall with the opposite rotation direction of the blades generated by the thermal buoyancy convection of the liquid silicon near the crucible wall; thus, when pulling a rectangular ingot, the relative speed of the liquid silicon flow along the circumference of the crucible wall caused by the low-speed rotation of the crucible is approximately zero, similar to the state when the crucible does not rotate, which is more conducive to reducing the oxygen content of the crucible caused by the crucible rotation.

[0076] The liquid silicon flow rising due to buoyancy is divided into a "boundary layer" and a "boundary outer layer". When pulling a rectangular silicon single crystal, the thickness of the liquid silicon in the boundary layer is on the order of (3 - 5) millimeters, the rising speed of the liquid silicon in the boundary layer is on the order of several (1 - 5) millimeters per second, and the rising rate of the liquid silicon in the boundary outer layer is on the order of (2 - 7) centimeters per second. In order to improve the suppression effect, the height of the blades of the present invention is greater than the thickness of the boundary layer. A higher blade height can obtain a stronger pressing effect, but the surface area of the quartz exposed in the liquid silicon will also increase. The prior art can help obtain the optimal blade height; the suppression angle of the blades is related to the crucible rotation rate. By adjusting , a relatively small crucible rotation rate and a satisfactory pressing effect can be obtained. During the pulling process of a silicon single crystal, the purpose of oxygen control can be achieved by adjusting the angular velocity of the crucible rotation.

[0077] On the one hand, by suppressing the thermal convection speed, the thickness of the boundary layer can be increased, and the oxygen impurity distribution gradient in the boundary layer can be reduced; on the other hand, by suppressing the thermal convection speed near the original boundary outer layer, for example, reducing it to less than 10 mm / s, the effective diffusion coefficient of oxygen impurities can be reduced. The reduction of the oxygen impurity distribution gradient and the diffusion coefficient makes the amount of oxygen impurities entering the liquid silicon per unit time decrease.

[0078] The reason for arranging 4 or 2n + 2m blades is based on the C4 or C2 rotational symmetry relationship of the crucible. Each pair of opposite two "protrusions" has a C2 rotational symmetry blade arrangement. Further, there is a C4 rotational symmetry blade arrangement. Generally, a quartz crucible with a C4 rotational symmetry relationship is used to pull a silicon single crystal rod with a square cross-section, and a quartz crucible with only a C2 rotational symmetry relationship is used to pull a silicon single crystal ingot with a rectangular cross-section.

[0079] Preferably, the suppression angle , (which can be 46°, 49°, 52°, 55°, 58°, 61°, 64°, 67°, 70°, 75°, 80°, etc.). A larger suppression angle can reduce the angular velocity ω of the crucible rotation, which is beneficial to the stability of the internal heat field and flow field in the crucible.

[0080] Furthermore, the quartz crucible has two mutually perpendicular axes of symmetry in the horizontal cross-section, and the most prominent points of the respective protruding parts are all on the same circumscribed circle-like shape. The ratio of the maximum transverse diameter to the minimum transverse diameter of the circumscribed circle-like shape is between 1 and 1.1, and the ratio of the widths of two adjacent protruding parts is between 1 and 1.4. The relatively high rotational symmetry of the crucible outer edge facilitates the rotation of the crucible and the symmetric design of the heat field, and the appropriate ratio of the widths of two adjacent protruding parts is beneficial to pulling a silicon single crystal ingot with a rectangular cross-section.

[0081] Furthermore, the height of the blade is , .

[0082] Preferably, the height of the blade is , (which can be 12mm, 15mm, 18mm, 20mm, 22mm, 25mm, 27mm, 30mm, 33mm, 35mm, 39mm, 41mm, 43mm, 45mm, 47mm, 50mm, etc.).

[0083] Furthermore, in the area between two adjacent protruding parts, the raised blades are not provided, and the blade clusters provided at the four protruding parts are isolated from each other and not connected. Such a design is because the connection part of the four protruding parts does not need heating and the heat convection intensity is relatively low.

[0084] Preferably, the tops of the four outwardly protruding parts are arc-shaped, and the ratio of the small transverse diameter to the large transverse diameter of the quartz crucible is between 0.5 and 0.9 (which can be 0.5, 0.52, 0.56, 0.58, 0.62, 0.65, 0.67, 0.71, 0.75, 0.79, 0.82, 0.84, 0.87, 0.9, etc.). The requirement for the ratio of the large and small transverse diameters is beneficial to forming a crucible environment for pulling a silicon single crystal ingot with a rectangular cross-section at a relatively low cost.

[0085] Furthermore, the suppression angle of the blade and the angular velocity of the rotation of the quartz crucible, the distance between the blade and the z-axis, and the liquid silicon heat convection rising rate of the first boundary outer layer of liquid silicon at the blade position on the inner surface of the quartz crucible when there is no blade have the following relationship:

[0086]

[0087] Wherein:

[0088] : coefficient ;

[0089] : the angular velocity of the quartz crucible rotation (in radians);

[0090] : the distance between the blade and the z-axis;

[0091] : the upward rate of thermal convection of liquid silicon in the outermost layer of the first boundary of liquid silicon without blades at the blade position on the inner surface of the crucible.

[0092] Understandably, the tops of the four outwardly protruding portions are arc-shaped, and the distance between the blade and the z-axis is different, and the inhibition angles of the blades at different positions at the top of the protruding portion can be the same or different. When the inhibition angles of the blades at different positions at the top of the protruding portion are different, it is beneficial for the blades to have different effects of inhibiting the liquid silicon flow at different positions, so as to improve the overall inhibition effect.

[0093] Furthermore, the cross-section of the blade is a serrated asymmetric cross-section, and the front angle of the blade cross-section is , 75° ≤ ≤ 95° (which can be selected as 75°, 77°, 82°, 85°, 87°, 89°, 91°, 93°, 95°, etc.); the rear angle of the blade cross-section is , 5° ≤ <75° (which can be selected as 5°, 9°, 11°, 24°, 33°, 43°, 55°, 62°, 68°, 71°, 74°, etc.);

[0094] In a preferred solution, the cross-section of the blade is a serrated asymmetric cross-section, and the front angle of the "serration" of the blade is relatively steep and the rear angle of the blade is relatively gentle. The beneficial effect of such an arrangement is that it is beneficial to form a relatively gentle laminar eddy current between the blades, preventing the formation of a violent turbulent eddy current from causing excessive impact and corrosion on the quartz crucible wall; it is beneficial to minimize the contact area between the liquid silicon and the crucible and reduce the path for impurity oxygen to enter the liquid silicon.

[0095] Furthermore, the distance between two adjacent said blades is s, (which can be selected as 21mm, 26mm, 31mm, 36mm, 41mm, 46mm, 51mm, 56mm, 61mm, 66mm, 71mm, 76mm, 81mm, 86mm, 91mm, 96mm, 100mm, etc.);

[0096] Alternatively, the distance between two adjacent ones of the blades is s, (optionally 110 mm, 120 mm, 130 mm, 140 mm, 150 mm, 160 mm, 170 mm, 180 mm, 190 mm, 200 mm, etc.).

[0097] The settings of the blade shape and spacing are for the effectiveness of suppressing buoyancy heat convection, minimizing the exposed area of quartz as much as possible, and reducing turbulent eddies.

[0098] In a second aspect, the present invention provides a quartz crucible with a non-rectangular or non-circular cross-section for pulling a rectangular single crystal silicon.

[0099] The inner cavity pattern of the quartz crucible in the xy plane cross-section has four outwardly protruding portions. On the bottom surface of the inner cavity of the quartz crucible, one or more rotors protruding relative to the bottom surface of the inner cavity of the quartz crucible are rotationally arranged around the z-axis. The rotors are rotationally arranged around the z-axis, and the rotation direction of the rotors is opposite to the rotation direction of the quartz crucible. A point P on the contour line of the rotor has a cutting-in angle , and the cutting-in angle ranges from 2° < < 80° (optionally 3°, 5°, 9°, 11°, 24°, 33°, 43°, 55°, 62°, 68°, 71°, 73°, 75°, 77°, 79°, etc.);

[0100] Furthermore, the height of the rotor is , .

[0101] Preferably, the height of the rotor is , (optionally 11 mm, 13 mm, 19 mm, 23 mm, 27 mm, 32 mm, 36 mm, 39 mm, 42 mm, 45 mm, 47 mm, 49 mm, 50 mm, etc.).

[0102] The rotor of the second non-rectangular or non-circular cross-section quartz crucible for pulling a rectangular single crystal silicon, in cooperation with the rotation of the quartz crucible (for a crucible with a right-handed rotor, the crucible rotates to the left; for a crucible with a left-handed rotor, the crucible rotates to the right), its cutting-in angle generates a centripetal pressing liquid silicon flow opposite to the direction of the liquid silicon heat convection at the bottom of the crucible, balancing and restraining the heat convection generated by the buoyancy of the liquid silicon, thereby reducing the intensity of the erosion of the quartz crucible wall by the liquid silicon and reducing the total amount of impurity oxygen entering the liquid silicon from the quartz crucible wall.

[0103] With the centripetal vortex effect of the rotor at the bottom of the crucible, a centripetal and upward liquid silicon eddy current is generated from the bottom of the crucible. The eddy current path is similar to the flared liquid flow generated upward by an eddy current nozzle. Its influence on the flow direction of liquid silicon is similar to crystal rotation, but it has more beneficial advantages than crystal rotation. First, the power of the technology of the present invention is at the bottom of the liquid silicon, while the power of crystal rotation is on the surface of the liquid silicon. The present invention generates a centripetal and upward liquid silicon eddy current from the bottom of the liquid silicon, and its rising path is in the shape of an upward flared opening, which does not directly impact the liquid silicon near the crystallization interface. Moreover, the liquid silicon with a lower temperature at the bottom of the crucible flows toward the crystallization interface. Therefore, it can achieve the purpose of reducing the temperature gradient of the liquid silicon near the crystallization interface and controlling the depth of the concave pit on the crystallization plane. Compared with the prior art, it can also slow down the degree of reduction of the drawing speed. Additionally, by reducing the disturbance to the central part of the crystallization interface, it can maintain a higher impurity concentration near the crystallization interface, increase the effective segregation coefficient of n-type impurities, reduce the effective segregation coefficient of impurity oxygen, and improve the effective segregation coefficient of n-type impurities, which is beneficial for n-type impurities to enter the silicon single crystal, reduce the longitudinal concentration gradient of n-type impurities in the silicon single crystal rod, make the doping uniform, and draw a longer silicon single crystal rod; reducing the effective segregation coefficient of impurity oxygen is beneficial for reducing the entry of impurity oxygen into the silicon single crystal and reducing the oxygen impurity content of the silicon single crystal rod.

[0104] The cutting-in angle of the rotor The angle setting is considered in view of the characteristics of different types of helical lines to improve the pressing efficiency of liquid silicon.

[0105] The main beneficial effect of the rotor cross-section being set as a serrated asymmetric cross-section is the same as that of the blade; the height of the rotor Different settings are beneficial for adjusting the suppression of the thermal convection of liquid silicon and the intensity of the centripetal and upward liquid silicon eddy current.

[0106] Preferably, the projection curve of the rotor on the inner cavity bottom surface of the quartz crucible in the xy plane is a helix, and the cutting-in angle gradually becomes smaller with the increase of the distance from the z-axis , and the change range is 2° < < 80°, and the angle change range depends on the type and number of spiral lines.

[0107] Furthermore, there is the following numerical relationship among the cutting-in angle of a point P on the contour line of the rotor, the flow rate of the liquid silicon on the outer layer of the second boundary, the angular velocity (in radians) of the rotation of the quartz crucible, and the distance between a point P on the rotor contour line and the z-axis:

[0108]

[0109] Wherein:

[0110] : coefficient ;

[0111] : the flow rate of liquid silicon at the second boundary outer layer of pure thermal convection at the bottom surface of the inner cavity of the crucible where the rotor is located when there is no rotor

[0112] : cutting angle

[0113] : the distance between a point P on the rotor contour line and the z-axis

[0114] With the aid of this relational expression, it is possible to:

[0115] 1. According to varying with , design the line type of the rotor contour line with variable angle, so that the flow of liquid silicon is smoother and closer to laminar flow, to ensure the stability of the flow field in the liquid silicon and ensure the flow field adaptability of pulling a silicon single crystal ingot with a rectangular cross section;

[0116] 2. Used to design the control curve of the angular velocity of the crucible during the crystal pulling process As the depth of liquid silicon in the crucible decreases, decreases and changes

[0117] In the third aspect, the present invention provides a third non-rectangular or circular cross-section quartz crucible for pulling a rectangular silicon single crystal. The inner cavity pattern of its cross-section in the xy plane has four outwardly protruding parts. On the inner cavity surface of the quartz crucible at the top of the four outwardly protruding parts, 4u or 2n + 2m blades protruding relative to the inner surface of the quartz crucible are arranged around the z-axis in a rotational manner, similar to the blades of the first non-rectangular or circular cross-section quartz crucible for pulling a rectangular silicon single crystal; and, on the bottom surface of the inner cavity of the quartz crucible, one or more rotors protruding relative to the bottom surface of the inner cavity of the quartz crucible are arranged around the z-axis in a rotational manner, similar to the rotors of the second non-rectangular or circular cross-section quartz crucible for pulling a rectangular silicon single crystal. The blades and the rotors have the same rotational direction. Understandably, the third quartz crucible for pulling a silicon single crystal combines the effects of the first and second quartz crucibles for pulling a silicon single crystal and can have a better synergistic effect.

[0118] Fourth aspect, the present invention provides a method for growing a rectangular silicon single crystal ingot by the Czochralski method. Using the quartz crucible provided in the first aspect, during the crystal growth process, the silicon single crystal ingot and the quartz crucible rotate synchronously and in the same direction around the z-axis. For the quartz crucible with the right-handed blades, the rotation direction of the crucible is left-handed; for the quartz crucible with the left-handed blades, the rotation direction of the crucible is right-handed. The outer edge linear velocity of the rotation of the quartz crucible is (10~350) mm / s. The outer edge linear velocity of the rotation of the quartz crucible can be determined according to the formula .

[0119] Fifth aspect, the present invention provides another method for growing a rectangular silicon single crystal ingot by the Czochralski method. Using the quartz crucible provided in the second aspect, during the crystal growth process, the quartz crucible and the rectangular silicon single crystal ingot rotate in the same direction and synchronously around the z-axis. For the quartz crucible with the right-handed rotors, the rotation direction of the crucible is left-handed; for the quartz crucible with the left-handed rotors, the rotation direction of the crucible is right-handed. The outer edge linear velocity of the rotation of the quartz crucible is (10~420) mm / s. The outer edge linear velocity of the rotation of the quartz crucible can be determined according to the formula .

[0120] Sixth aspect, the present invention provides another method for growing a rectangular silicon single crystal ingot by the Czochralski method. Using the quartz crucible provided in the third aspect, during the crystal growth process, the quartz crucible and the silicon single crystal ingot rotate in the same direction and synchronously around the z-axis. For the quartz crucible with the right-handed rotors, the rotation direction of the crucible is left-handed; for the quartz crucible with the left-handed rotors, the rotation direction of the crucible is right-handed; the outer edge linear velocity of the rotation of the quartz crucible is (10~350) mm / s.

[0121] By locally and intermittently arranging the "blades" on the convex part of the crucible and / or the "rotors" at the bottom of the crucible, and cooperating with the low-speed crystal rotation in the same direction and synchronously with the crucible rotation, the present invention achieves the purpose of suppressing thermal convection, reducing oxygen, and controlling oxygen, while retaining the beneficial effects brought by stopping the crystal rotation when pulling a single crystal with a rectangular cross-section, that is, it not only maintains the stability of the small environment at the front of the crystallization interface of the silicon single crystal, but also increases the temperature gradient on the liquid silicon side of the crystallization interface, achieving the purpose of reducing oxygen, controlling oxygen, controlling the content of n-type impurities, and controlling the flatness of the crystallization plane. BRIEF DESCRIPTION OF THE DRAWINGS

[0122] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the drawings required for the embodiments. It should be understood that the following drawings only show some embodiments of the present invention, and therefore should not be regarded as limiting the scope. For those of ordinary skill in the art, without creative efforts, other related drawings can also be obtained based on these drawings.

[0123] Figure 1 It is a longitudinal sectional schematic view of the quartz crucible of Embodiment 1 of the present invention; after adding the spiral rotor 12 at the bottom, it is also the longitudinal sectional schematic view of the quartz crucible of Embodiment 2.

[0124] Figure 2 Corresponding to Embodiment 1 of the present invention Figure 1 The partial view in the B-B direction in

[0125] Figure 3 It is a top view schematic of the quartz crucible of Embodiment 2 of the present invention. Except for the spiral rotor 12 at the bottom, it is also the top view schematic of the quartz crucible of Embodiment 1.

[0126] Figure 4 Corresponding to Embodiment 2 of the present invention Figure 3 The partial view in the A-A direction in

[0127] Explanation of reference numerals:

[0128] 1 - Quartz crucible; 11 - Blade; β1 - Blade rake angle; γ1 - Blade clearance angle; h1 - Blade height; α1 - Inhibiting angle; 12 - Rotor; α2 - Cutting-in angle; β2 - Rotor rake angle; γ2 - Rotor clearance angle; h2 - Rotor height; 2 - Heater; 3 - z-axis; D - Large transverse diameter of the crucible; D1 - First large transverse diameter of the crucible; D2 - Second large transverse diameter of the crucible; d - Small transverse diameter of the crucible; 6 - Silicon single crystal ingot. Detailed implementation manners

[0129] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Usually, the components of the embodiments of the present invention described and illustrated in the accompanying drawings here can be arranged and designed in various different configurations.

[0130] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed present invention, but merely represents selected embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the scope of protection of the present invention.

[0131] It should be noted that: similar reference numerals and letters represent similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0132] In the description of the present invention, it should be noted that if terms such as "upper", "lower", "inner", "outer", etc. are used to indicate the orientation or positional relationship, it is based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the invention product is usually placed during use. This is 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 should not be construed as a limitation to the present invention.

[0133] Example 1

[0134] As Figure 1 、 Figure 2 shown and referring to Figure 3 , the embodiment of the present invention provides a quartz crucible 1 for growing a silicon single crystal with a square cross-section by the Czochralski method. The inner cavity pattern of its cross-section in the xy plane has four outwardly protruding portions, showing C4 rotational symmetry. The protruding portions are arched. On the inner cavity surface of the quartz crucible 1 within the range of 2×35° symmetric about the connection line between the top of the four protruding portions and the symmetry center of the pattern, 4u relatively protruding blades 11 are arranged around the z-axis 3, where u = 7. In the region between two adjacent protruding portions, the protruding blades 11 are not provided, and the blade clusters provided on the four protruding portions are isolated from each other and not connected.

[0135] The rotation direction of the blade 11 is opposite to that of the quartz crucible 1. The blade 11 has a blade inhibition angle α1, α1 75°; the blade height h1 of the blade 11 is greater than the first boundary layer thickness δ1 of the liquid silicon on the inner cavity surface near the blade 11 of the crucible 1. Here, δ1 in this embodiment is , and the blade height h1, h1 = 20 mm.

[0136] The large transverse diameter D of the quartz crucible 1 (including the first large transverse diameter D1 and the second large transverse diameter D2), D1 = D2 = D = 820 mm, the small transverse diameter d of the crucible, d = 574 mm, d / D = 0.7, and the height is 650 mm, where the height of the cylindrical part is 450 mm. The rotation direction of the blade 11 is right-handed, opposite to that of the quartz crucible 1.

[0137] In this embodiment, the cross-section of the blade 11 is a serrated asymmetric cross-section, with a blade rake angle β1 = 90° and a blade clearance angle γ1 = 30°; the distance between two adjacent blades is about 60 mm.

[0138] In this embodiment, during the growth of single crystal silicon, the quartz crucible 1 rotates about the crucible rotation z-axis 3. The quartz crucible 1 with the right-handed blades 11 rotates in a left-handed direction. The drawn single crystal silicon ingot 6 rotates in the same direction and synchronously with the quartz crucible 1. The initial rotation speed of the quartz crucible 1 during drawing is about 1.36 revolutions per minute. Thereafter, the crucible rotation decreases linearly. When the liquid silicon surface drops to the end of the blade 11, the rotation speed of the quartz crucible 1 is about 0.23 revolutions per minute.

[0139] In the prior art, quartz crucibles 1 of the same shape and size are used to draw single crystal silicon ingots with square cross-sections, which have strict requirements for the distribution of liquid silicon temperature and flow field. Both the crucible rotation and the crystal rotation are "0". Due to the lack of the suppression of thermal convection by the inertial centrifugal force of the liquid silicon generated by the crystal rotation, the liquid silicon thermal convection on the first boundary outer layer of the inner cavity surface of the quartz crucible at the top of the four outwardly protruding portions forms a typical natural convection eddy in the meridian plane, and its flow rate reaches 60 mm / s. On the one hand, this natural convection eddy strongly scours the crucible surface, causing a large amount of impurity oxygen to enter the liquid silicon and effectively bringing it to the crystal growth surface; on the other hand, a large amount of high-temperature liquid silicon flows directly towards the crystal surface, increasing the temperature at the center of the crystallization surface, resulting in a severely concave surface on the crystal surface and reducing the growth rate.

[0140] In this embodiment, by means of the appropriately arranged blades 11 and their crucible rotation settings, on the one hand, the lateral flow of the liquid silicon caused by the crucible rotation can be balanced and the natural convection eddy at the hot wall of the crucible can be suppressed, reducing its flow rate from 60 mm / s to 10 mm / s. According to empirical data, the beneficial effect is to directly reduce the oxygen impurity content in the crystal by 35%.

[0141] Embodiment 2

[0142] Such as Figure 3 、 Figure 4 and with reference to Figure 1 , the embodiment of the present invention provides a quartz crucible 1 for growing single crystal silicon with a length-width ratio of 1.3 in the cross-section by the Czochralski method. Its inner cavity pattern in the xy-plane cross-section has four outwardly protruding portions, showing C2 rotational symmetry.

[0143] The protruding portions are arched. Within a range of 2×30° symmetric about the line connecting the top of the two narrower protruding portions to the symmetry center of the pattern, 2n blades protruding relative to the inner surface of the quartz crucible 1 are arranged around the z-axis 3; within a range of 2×40° symmetric about the line connecting the top of the two wider protruding portions to the symmetry center of the pattern, 2m blades protruding relative to the inner surface of the quartz crucible 1 are arranged around the z-axis 3. Where n = 6 and m = 7.

[0144] In the region between two adjacent said protruding portions, no blades 11 are provided, and the blade clusters provided on the four protruding portions are isolated from each other and not connected.

[0145] The quartz crucible 1 has two mutually perpendicular axes of symmetry in the xy-plane cross-section. The most prominent vertices of each protruding part are on the same circumscribed circle. The ratio of the width of two adjacent protruding parts is narrow: wide = 1:1.3.

[0146] In the area between two adjacent protruding parts, no raised blades 11 are provided. The blade clusters provided on the four protruding parts are isolated from each other and not connected.

[0147] The blade 11 has an inhibitory angle α1, α1 = 60°; the blade height h1 of the blade 11 is greater than the first boundary layer thickness δ1 of the liquid silicon on the inner cavity surface near the blade 11 of the quartz crucible 1. Here, δ1 is 2 mm - 5 mm in this embodiment, and the blade height h1, h1 = 16 mm.

[0148] In this embodiment, the cross-section of the blade 11 is a serrated asymmetric cross-section, its blade front angle β1 = 90°, and its blade rear angle γ1 = 30°; the distance between two adjacent blades is about 70 mm.

[0149] In this embodiment, during the growth of the silicon single crystal, the quartz crucible 1 rotates around the crucible rotation z-axis 3. The quartz crucible 1 with the right-handed blades 11 rotates in a left-handed direction, and the rectangular silicon single crystal ingot 6 drawn rotates in the same direction and synchronously with the quartz crucible 1. The initial crucible rotation speed during drawing: 1.5 revolutions per minute, and then the crucible rotation linearly decreases. When the liquid silicon surface drops to the end of the blade 11, the rotation speed of the quartz crucible 1 is 0.25 revolutions per minute.

[0150] In this embodiment, the large transverse diameter D of the quartz crucible 1, D1 = D2 = D = 820 mm, the small transverse diameter d of the crucible, d = 574, d / D = 0.8, and the height is 650 mm, where the height of the cylindrical part is 450 mm. The rotation direction of the blade 11 is right-handed, which is opposite to the rotation direction of the quartz crucible 1.

[0151] In this embodiment, on the inner cavity bottom surface of the quartz crucible 1, 4 rotors 12 protruding relative to the inner cavity surface of the quartz crucible 1 are symmetrically distributed at the center. The projection of the rotor 12 in the xy-plane is a part of a similar involute with the center of the base circle on the crucible z-axis 3. The 4 rotors 12 arranged are rotationally symmetrically arranged around the crucible z-axis 3 in a C4 pattern, and the cutting-in angle α2 of the rotor gradually changes continuously from 4° to 76° from the outside to the inside.

[0152] In this embodiment, the protruding rotor height h2 of the rotor 12 is 20 mm; the cross-section of the rotor 12 is a serrated asymmetric cross-section, its rotor front angle β2 is 90°, and its rotor rear angle γ2 is 30°; the rotation direction of the rotor 12 is right-handed.

[0153] In this embodiment, during the growth of the silicon single crystal, the quartz crucible 1 rotates around the crucible z-axis 3. The quartz crucible 1 with the right-handed rotors 12 rotates in a left-handed direction.

[0154] In this embodiment, during the growth of the silicon single crystal ingot 6, the rotation of the quartz crucible 1 is coordinated with the rotation of the rotor 12 at the inner bottom of the quartz crucible 1. On the one hand, the rotor 12 will generate a centripetal forced liquid silicon flow pressure near the bottom of the quartz crucible 1. This forced liquid silicon flow pressure will restrain the liquid silicon thermal convection rising along the inner wall of the quartz crucible 1, reduce the intensity of the liquid silicon scouring the inner wall of the crucible 1, and reduce the impurity oxygen entering the liquid silicon. On the other hand, this forced liquid silicon flow pressure, the eddy current formed by it has the effect of pumping the liquid silicon at a lower temperature at the bottom of the quartz crucible 1 to the center part of the crystallization interface of the silicon single crystal ingot 6, which can improve the flatness of the crystallization plane of the silicon single crystal ingot 6, and has the beneficial effects of reducing the internal stress in the crystal and improving the uniformity of the impurity distribution in the xy cross-sectional plane.

[0155] Similar to Embodiment 1, when a quartz crucible 1 with the same shape and size in the prior art is used to draw a silicon single crystal ingot 6 with a rectangular cross-section, there are strict requirements for the liquid silicon temperature and the velocity vector distribution of the flow field. The rotating silicon single crystal ingot 6 with a rectangular cross-section will cause the distribution of the surrounding thermal field to change periodically, which is not conducive to the growth of the silicon single crystal ingot 6 with a rectangular cross-section. Therefore, both the crucible rotation and the crystal rotation are "0". Due to the lack of the inhibition of the liquid silicon inertial centrifugal force generated by the crystal rotation on the thermal convection, the liquid silicon thermal convection on the first boundary outer layer of the inner cavity surface of the quartz crucible at the top of the four outwardly protruding parts forms a typical natural convection eddy current in the meridian plane, and its flow rate reaches 60 mm / s. On the one hand, this natural convection eddy current strongly scours the crucible surface, causing a large amount of impurity oxygen to enter the liquid silicon and effectively bringing it to the crystal growth surface. On the other hand, a large amount of high-temperature liquid silicon flows directly towards the crystal surface, increasing the temperature of the center part of the crystallization surface, resulting in a severely concave surface on the crystal surface and reducing the growth rate.

[0156] This embodiment is similar to Embodiment 1. By means of the appropriately arranged blades 11 and the setting of low-speed crucible rotation, on the one hand, it can balance the lateral flow of the liquid silicon caused by the crucible rotation and inhibit the natural convection vortex at the hot wall of the crucible, reducing its flow rate to 10 mm / s. According to empirical data, its beneficial effect is to directly reduce the oxygen impurity content in the crystal by 35%. On the other hand, it hinders the high-temperature liquid silicon from flowing directly towards the crystal crystallization surface, reducing the temperature of the center of the crystal crystallization surface by 1 °C. Its beneficial effects are as follows:

[0157] 1. Change the effective segregation coefficient of the impurity to make it closer to 1. For n-type impurities, its effective segregation coefficient can be increased to make the doping more uniform and the concentration gradient lower; for impurity oxygen, its effective segregation coefficient is reduced, thereby reducing the oxygen impurity content in the crystal.

[0158] 2. According to the formula:

[0159]

[0160] Where:

[0161] n: The vector perpendicular to the solid-liquid interface at the solidification front of the silicon single crystal (positive downward);

[0162] : The growth rate of the silicon single crystal (along the direction of vector n);

[0163] ρ s : The density of the silicon single crystal;

[0164] L: The latent heat of crystallization of silicon;

[0165] : The thermal conductivity of the silicon crystal;

[0166] : The thermal conductivity of liquid silicon;

[0167] : The temperature gradient along the direction of vector n on the silicon crystal side of the crystallization interface;

[0168] : The temperature gradient along the direction of vector n on the liquid silicon side of the crystallization interface.

[0169] On the premise of the same internal stress in the crystal, the reduction of the second term in the above formula is beneficial to maintaining a relatively high growth rate of the silicon crystal .

[0170] Furthermore, when the liquid silicon level in the quartz crucible is relatively high, the pressing effect of the blades on the side of the crucible is more obvious, and when the liquid silicon level in the quartz crucible is relatively low, the restraint effect of the rotors at the bottom of the crucible is more obvious. The cooperation between the two is complementary, which is more conducive to regulating and controlling the entire crystal pulling process and improving the product quality.

[0171] In summary, compared with the prior art technical solution of controlling the oxygen content in the silicon single crystal ingot by applying an external magnetic field, the technical solution provided by the present invention has significant cost advantages and cost reduction potential, which is of great significance to the development of the industry.

[0172] The above embodiments are only preferred embodiments of the present invention and are not used to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A quartz crucible with a non-rectangular or non-circular cross-section for pulling rectangular silicon single crystals, the inner cavity pattern of its cross-section in the xy plane having four outwardly protruding portions, characterized in that, On the inner surface of the quartz crucible within a range not greater than 2×42° that is symmetric about the line connecting the top of the protruding part and the center of symmetry of the figure, 4u or 2n + 2m blades protruding relative to the inner surface of the quartz crucible are arranged in a rotation around the z-axis, where u, n, and m are integers greater than or equal to 1. On the inner surface of the quartz crucible at the top of one of the four outwardly protruding parts, u, n, or m of the blades are arranged. The angle between the blade and the xy plane, i.e., the suppression angle , , the rotation direction of the protruding blade is opposite to that of the quartz crucible; the height of the blade is , .

2. The quartz crucible according to claim 1, wherein The suppression angle , .

3. The quartz crucible according to claim 1, characterized in that, The quartz crucible has two mutually perpendicular symmetry axes in the xy plane cross-section, and the most prominent point of each of the protruding parts is on the same circumscribed similar circle. The ratio of the maximum transverse diameter to the minimum transverse diameter of the circumscribed similar circle is between 1 and 1.1, and the ratio of the widths of two adjacent protruding parts is between 1 and 1.

4.

4. The quartz crucible according to claim 1, characterized in that, The height of the blade is , .

5. The quartz crucible according to claim 1, wherein, In the area between two adjacent protruding parts, the raised blades are not provided, and the blade clusters provided at the four protruding parts are isolated from each other and not connected.

6. The quartz crucible according to claim 1, characterized in that, The tops of the four outwardly protruding parts are arc-shaped, and the ratio of the small transverse diameter to the large transverse diameter of the quartz crucible is 0.5 to 0.

9.

7. The quartz crucible according to claim 1, characterized in that, The tops of the four outwardly protruding parts are arc-shaped, and the ratio of the small transverse diameter to the large transverse diameter of the quartz crucible is 0.6 to 0.

8.

8. The quartz crucible according to claim 1, characterized in that, The suppression angle of the blade and the angular velocity of the rotation of the quartz crucible , the distance between the blade and the z-axis , the liquid silicon thermal convection upward rate of the first boundary outer layer of liquid silicon at the blade position on the inner surface of the quartz crucible when there is no blade have the following relationship: Wherein: : Coefficient; : Angular velocity of quartz crucible rotation, in radians; : The distance between the blade and the z-axis; : The liquid silicon thermal convection upward rate of the outer layer of the first boundary of liquid silicon when there is no blade at the blade position on the inner surface of the quartz crucible.

9. The quartz crucible according to claim 1, characterized in that, The blades located on the inner surface of the protruding part of the quartz crucible have at least one of the following characteristics: 1) The cross-section of the blade is a serrated asymmetric cross-section, and the front angle of the blade cross-section is , 75° ≤ ≤ 95°; the rear angle of the blade cross-section is , 5° ≤ < 75°; 2) The distance between two adjacent ones of the blades is s, ; 3) The distance between two adjacent blades is s, .

10. A quartz crucible with a non-rectangular or non-circular cross-section for pulling rectangular single crystal silicon, having four outwardly protruding portions in the inner cavity pattern of its cross-section in the xy plane, characterized in that, On the bottom surface of the inner cavity of the quartz crucible, one or more rotors are arranged to rotate around the z-axis and are raised relative to the bottom surface of the inner cavity of the quartz crucible. The rotors are arranged to rotate around the z-axis, and the rotation direction of the rotors is opposite to that of the quartz crucible. A point P on the contour line of the rotor has an incision angle , cutting angle The range is 2°< <80°;The height of the rotor is , .

11. The quartz crucible according to claim 10, characterized in that, The height of the rotor is , .

12. The quartz crucible according to claim 10, characterized in that, The projection curve of the rotor on the bottom surface of the inner cavity of the quartz crucible in the xy plane is a spiral, and the cutting angle gradually decreases with the increase of the distance from the z-axis , and the change range is 2° < < 80°.

13. The quartz crucible according to claim 10, characterized in that, The cutting-in angle of a point P on the rotor profile line , the flow rate of liquid silicon in the outer layer of the second boundary , and the angular velocity of rotation of the quartz crucible in radians , the distance between a point P on the rotor profile line and the z-axis There is the following relationship numerically: Wherein: : Coefficient; : The flow rate of liquid silicon in the second boundary outer layer of pure thermal convection without a rotor at the bottom surface of the rotor in the inner cavity of the crucible; : cutting angle; : The distance between a point P on the rotor profile line and the z-axis.

14. A quartz crucible with a non-rectangular or circular cross-section for pulling rectangular single crystal silicon, the inner cavity pattern of its cross-section in the xy plane has four outwardly protruding portions, characterized in that, On the inner cavity surface of the quartz crucible at the tops of the four outwardly protruding parts, 4u or 2n + 2m blades as claimed in any one of claims 1-9, which protrude relative to the inner surface of the quartz crucible, are arranged in rotation around the z-axis; and, on the bottom surface of the inner cavity of the quartz crucible, one or more rotors as claimed in any one of claims 10-13, which protrude relative to the bottom surface of the inner cavity of the quartz crucible, are arranged in rotation around the z-axis, and the blades and the rotors have the same rotation direction.

15. A method for growing a rectangular single crystal silicon ingot by the Czochralski method, characterized in that, When using the quartz crucible according to any one of claims 1-9, during the crystal growth process, the rectangular single crystal silicon ingot and the quartz crucible rotate synchronously and in the same direction around the z-axis. For the quartz crucible with the right-handed blades, the rotation direction of the crucible is left-handed; for the quartz crucible with the left-handed blades, the rotation direction of the crucible is right-handed. The linear velocity of the outer edge of the rotation of the quartz crucible is 10-350 / second.

16. A method for growing a rectangular single crystal silicon ingot by the Czochralski method, characterized in that, When using the quartz crucible according to any one of claims 10-13, during the crystal growth process, the quartz crucible and the rectangular single crystal silicon ingot rotate synchronously in the same direction with the z-axis as the axis. For the quartz crucible with the right-handed rotor, the rotation direction of the crucible is left-handed; for the quartz crucible with the left-handed rotor, the rotation direction of the crucible is right-handed, and the linear velocity of the outer edge of the rotation of the quartz crucible is 10-420 / second.

17. A method for growing a rectangular single crystal silicon ingot by the Czochralski method, characterized in that, Using the quartz crucible described in claim 10, during the crystal growth process, the quartz crucible and the silicon single crystal ingot rotate synchronously in the same direction around the z-axis. For the quartz crucible with the right-handed rotor, the rotation direction of the crucible is left-handed; for the quartz crucible with the left-handed rotor, the rotation direction of the crucible is right-handed; the linear velocity of the outer edge of the quartz crucible rotation is 10~350 / second.

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