A method and device for determining the amount of dopant and a computer storage medium

Abstract

The present invention discloses a method and device for determining the dosage of a dopant and a computer storage medium, and relates to the field of crystal pulling technology, so as to control the amount of impurity doping in the crystal growth process, thereby ensuring the quality of the crystal. The method comprises: determining the target impurity concentration of the crystal according to the target electrical parameters of the crystal; using a first impurity segregation model to process the impurity volatilization parameters before equal diameter, the impurity volatilization parameters in the equal diameter stage and the target impurity concentration of the crystal to obtain the impurity concentration of the melt at the end of the shoulder turn; using a second impurity segregation model to process the impurity volatilization parameters before equal diameter and the impurity concentration of the melt at the end of the shoulder turn to obtain the initial impurity concentration of the melt; determining the dosage of the dopant according to the initial impurity concentration of the melt. The device comprises a processor and a communication interface coupled to the processor; the processor is used to run a computer program or instruction to implement the method. The method provided by the present invention is used to determine the dosage of a dopant in a crystal material.

Description

Technical Field

[0001] The present invention relates to the field of crystal pulling technology, and in particular to a method and device for determining the feeding amount of a dopant, and a computer storage medium. Background Art

[0002] At present, the main basic material for photovoltaic power generation is gallium-doped P-type single crystal. Compared with the traditional boron-doped P-type single crystal, it avoids the formation of BO complexes and effectively reduces the initial light-induced degradation (LID), ensuring that P-type photovoltaic modules can maintain high efficiency, stability and reliability for a long time.

[0003] However, since the melting point of gallium is 29.78°C, it is easy to volatilize during the single crystal preparation process. Especially when it is carried out under vacuum conditions, the gas and liquid phases are in equilibrium during the crystal growth process, and the volatilization of impurities becomes very easy. The volatilization of impurity elements will cause a certain error between the measured resistivity and the target resistivity, which in turn affects the quality of the single crystal. At present, for the doping amount of gallium-doped single crystals, most of the existing single crystal manufacturers use quantitative doping method based on experience. The doping amount of each silicon rod is fixed, and the impact of gallium volatilization is not calculated, which makes the target resistivity of the crystal deviate greatly from the actual resistivity, greatly affecting the quality of the single crystal. Summary of the invention

[0004] The object of the present invention is to provide a method and device for determining the feeding amount of a dopant and a computer storage medium, so as to control the impurity doping amount during the crystal growth process, thereby ensuring the crystal quality.

[0005] In a first aspect, the present invention provides a method for determining the amount of a dopant to be fed, which is applied to a crystal pulling furnace. The crystal pulling furnace is used to pull a melt doped with volatile impurities into a crystal. The method for determining the amount of a dopant provided by the present invention comprises:

[0006] Determine the crystal target impurity concentration C based on the crystal's target electrical parameters s ;

[0007] The first impurity segregation model is used to process the impurity volatilization parameters before equal diameter, the impurity volatilization parameters of the equal diameter stage and the crystal target impurity concentration C s , obtain the impurity concentration C of the melt at the end of the shoulder L ;

[0008] The second impurity segregation model is used to process the impurity volatilization parameters before the equal diameter and the impurity concentration C of the melt at the end of the shoulder rotation. L , obtain the initial impurity concentration C of the melt;

[0009] Determine the dopant dosage m based on the initial impurity concentration C of the melt c .

[0010] In the case of adopting the above technical solution, when the target electrical parameters of the crystal are known to determine the target impurity concentration C of the crystal, s In the case of the first impurity segregation model, the impurity volatilization parameters before equal diameter, the impurity volatilization parameters at the equal diameter stage and the crystal target impurity concentration C s , the impurity concentration C of the melt at the end of the shoulder can be obtained L On this basis, the second impurity segregation model is used to process the impurity volatilization parameters before equal diameter and the impurity concentration C of the melt at the end of shoulder turning. L , and obtain the impurity concentration C of the melt at the end of the melting. At this time, the doping amount m of the dopant determined according to the impurity concentration C of the melt at the end of the melting c Then, according to the dopant dosage m c Adding dopants to the crystal material can ensure that there is basically no deviation between the actual electrical parameters (such as resistivity) of the crystal finally pulled by the crystal pulling furnace and the target electrical parameters (such as target resistivity), thereby improving the quality of the single crystal.

[0011] In a possible implementation, the target electrical parameter of the crystal is the target resistivity ρ of the crystal. 电 ; The target resistivity of the crystal ρ 电 With the crystal target impurity concentration C s Satisfy between:

[0012] In a possible implementation, the above-mentioned pre-equal diameter impurity volatilization parameters include: crystal weight, crucible radial parameters and the time from the end of melting to the end of shoulder turning.

[0013] The impurity volatilization parameters in the above-mentioned equal diameter stage include: crystal radial parameters, crystal pulling speed and crystal length.

[0014] In a possible implementation, the first impurity segregation model satisfies: in,

[0015] k is the impurity segregation coefficient; B is the impurity volatility coefficient; x is the solidification fraction per unit length; t s is the volatilization time of the first impurity, t s =t0+1 / v, t0 is the time from the end of the melt to the end of the shoulder, v is the crystal pulling speed; S s is the impurity volatilization area in the equal diameter stage, D1 is the crucible diameter of the crystal pulling furnace, D2 is the diameter of the crystal in the equal diameter process, V0 is the initial volume of the melt, V0 = M / ρ 密L , ρ 密L is the density of the melt, and M is the weight of the crystal.

[0016] In a possible implementation, the second impurity segregation model satisfies: B is the impurity volatility coefficient, t L is the time t0 from the end of melting to the end of shoulder turning; S L is the impurity volatilization area before equal diameter, D1 is the diameter of the crucible used to hold the melt; V0 is the initial volume of the melt, V0 = M / ρ 密L , ρ 密L is the melt density.

[0017] In a possible implementation, when there is no residual material in the crucible of the crystal pulling furnace, the initial impurity concentration C of the melt and the feed amount m of the dopant are c The relationship satisfies: m c =λ(CV0-N0), λ is the conversion constant, V0 is the initial volume of the melt, and N0 is the number of impurities contained in the crystal material.

[0018] When the unit of initial impurity concentration of the melt is atoms / cm 3 , CV0 determines the amount of impurities in the melt. For the convenience of measurement, the conversion constant can be defined to convert the amount of impurities in the melt into the weight or molar amount of the dopant in the melt. As for the value of λ, it is determined according to the target of the conversion. For example: when the dopant is gallium, the amount of impurities needs to be converted into the molar amount of the dopant, then λ=10 -23 / 6.023=1.66×10 -24 / mol; For example, when the dopant is gallium, the impurity quantity needs to be converted into the dopant weight, then λ = 69.72×10 -23 / 6.023=1.16×10 -22 g.

[0019] In a possible implementation, the above-mentioned crystal pulling furnace is used to pull multiple crystals. When the crystal pulling furnace finishes pulling the n-1th crystal, if there is residual melt in the crucible, according to the initial impurity concentration C of the melt of the nth crystal, h Determine the dopant feed amount m of the crystal pulling furnace for pulling the nth crystal ch include:

[0020] According to the impurity volatilization parameters before and after equalizing the diameter of the n-1 crystal pulled by the crystal pulling furnace, determine the number of impurities N contained in the residual melt in the crucible when the crystal pulling furnace finishes pulling the n-1 crystal. k ;

[0021] According to the number of impurities N contained in the residual melt in the crucible when the crystal pulling furnace pulls the n-1th crystal, k , the weight of the crystal material M of the nth crystal pulled by the crystal pulling furnace hThe initial impurity concentration C of the melt when the nth crystal is pulled by the crystal pulling furnace h , determine the dopant feed amount m for the crystal pulling furnace to pull the nth crystal ch .

[0022] In a possible implementation, the impurity volatilization parameters before the equal diameter of the n-1th crystal pulled by the crystal pulling furnace include: the initial impurity concentration C of the melt of the n-1th crystal pulled by the crystal pulling furnace q , the weight of the crystal material M of the crystal pulling furnace pulling the n-1th crystal q , the time t from the start of melting to the end of shoulder turning when the crystal pulling furnace pulls the n-1th crystal Lq , and the crucible radial parameters.

[0023] In a possible implementation, the impurity volatilization parameters after the crystal pulling furnace pulls the n-1th crystal with equal diameter include the crystal radial parameters, the crystal pulling speed and the length Q of the n-1th crystal. q .

[0024] In one possible implementation, N k =V k C lk ; C lk is the impurity concentration of the residual melt in the crucible when the crystal pulling furnace finishes pulling the n-1th crystal, V k It is the volume of residual melt in the crucible when the crystal pulling furnace finishes pulling the n-1th crystal. M q is the weight of the crystal of the n-1th crystal, m q is the weight of the n-1th crystal, ρ 密L is the melt density.

[0025] In one possible implementation, C Lq is the impurity concentration of the melt at the end of the shoulder when the crystal pulling furnace pulls the n-1th crystal; C q The initial impurity concentration of the melt when the crystal pulling furnace pulls the n-1th crystal.

[0026] k is the impurity segregation coefficient, B is the impurity volatility coefficient; S L is the impurity volatilization area before equal diameter, S s is the impurity volatilization area in the equal diameter stage, V q is the initial volume of the melt when the crystal pulling furnace pulls the n-1th crystal; t sq is the time it takes for impurities to volatilize when the crystal pulling furnace pulls the n-1th crystal, t sq =t Lq +Q q / v q ;tLq v is the time from the start of melting to the end of shoulder turning when the crystal pulling furnace pulls the n-1th crystal, q is the crystal pulling speed in the equal diameter process when the crystal pulling furnace pulls the n-1th crystal, Q q is the length of the n-1th crystal.

[0027] In a possible implementation, the above-mentioned crystal pulling furnace is used to pull multiple crystals. When the crystal pulling furnace finishes pulling the n-1th crystal, if there is residual melt in the crucible, the initial impurity concentration C of the melt of the crystal pulling furnace pulling the nth crystal is h The amount of dopant added to the crystal pulling furnace to pull the nth crystal is m ch The relationship satisfies: m ch =λ(C h V h -N k -N h ), n is an integer greater than or equal to 2, λ is a conversion constant, N h V is the number of impurities contained in the crystal material input to the crystal pulling furnace to pull the nth crystal, h is the initial volume of the melt in the crystal pulling furnace to pull the nth crystal, N k It is the number of impurities contained in the residual melt in the crucible when the crystal pulling furnace finishes pulling the n-1th crystal.

[0028] In a possible implementation, the dopant includes one or more of gallium, boron, phosphorus, arsenic, and antimony.

[0029] In a second aspect, the present invention also provides a device for determining the dosage of a dopant, comprising: a processor and a communication interface coupled to the processor; the processor is used to run a computer program or instruction to implement the method for determining the dosage of a dopant described in the first aspect or any possible implementation method of the first aspect.

[0030] The beneficial effects of the dopant dosage determination device provided in the second aspect are the same as the beneficial effects of the dopant dosage determination method described in the first aspect or any possible implementation of the first aspect, and are not elaborated here.

[0031] In a third aspect, the present invention further provides a computer storage medium having instructions stored therein, which, when executed, implements the method for determining the doping amount of the dopant described in the first aspect or any possible implementation of the first aspect.

[0032] The beneficial effects of the computer storage medium provided in the third aspect are the same as the beneficial effects of the method for determining the doping amount of the dopant described in the first aspect or any possible implementation of the first aspect, and are not elaborated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0034] Figure 1 A diagram showing an application scenario of a method for determining a dopant dosage provided by an embodiment of the present invention;

[0035] Figure 2 An example of a structural schematic diagram of a single crystal furnace is given;

[0036] Figure 3 The process of determining the doping amount of the dopant provided in the embodiment of the present invention Figure 1 ;

[0037] Figure 4 Principle for determining the doping amount of dopant provided in the embodiment of the present invention Figure 1 ;

[0038] Figure 5 The process of determining the doping amount of the dopant provided in the embodiment of the present invention Figure 2 ;

[0039] Figure 6 Principle for determining the doping amount of dopant provided in the embodiment of the present invention Figure 2 ;

[0040] Figure 7 A structural block diagram of a device for determining a dopant dosage provided by an embodiment of the present invention;

[0041] Figure 8 A schematic diagram of the hardware structure of an electronic device provided by an embodiment of the present invention;

[0042] Fig. 9 A schematic diagram of the structure of a chip provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0043] In order to clearly describe the technical solutions of the embodiments of the present invention, in the embodiments of the present invention, words such as "first" and "second" are used to distinguish the same items or similar items with basically the same functions and effects. For example, the first threshold and the second threshold are only used to distinguish different thresholds, and their order is not limited. Those skilled in the art can understand that words such as "first" and "second" do not limit the quantity and execution order, and words such as "first" and "second" do not necessarily limit them to be different.

[0044] It should be noted that, in the present invention, words such as "exemplary" or "for example" are used to indicate examples, illustrations or descriptions. Any embodiment or design described as "exemplary" or "for example" in the present invention should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as "exemplary" or "for example" is intended to present related concepts in a specific way.

[0045] In the present invention, "at least one" means one or more, and "plurality" means two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone, where A and B can be singular or plural. The character " / " generally indicates that the associated objects before and after are in an "or" relationship. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single or plural items. For example, at least one of a, b or c can mean: a, b, c, the combination of a and b, the combination of a and c, the combination of b and c, or the combination of a, b and c, where a, b, c can be single or multiple.

[0046] An embodiment of the present invention provides a method for determining a dopant dosage, which can be applied to a crystal pulling furnace. Figure 1 The following is an example of the application scenario of the method for determining the doping amount of the dopant provided in the embodiment of the present invention. Figure 1 As shown, the application scenario includes a terminal device 100, an information input device 200, a measuring unit 300, a weighing unit 400 and an industrial computer 500 of a crystal pulling furnace.

[0047] like Figure 1 As shown, the terminal device 100 may be a processor or a terminal device 100 with a display function such as a mobile phone or a tablet computer, which is used to determine the doping amount of the dopant. When the terminal device 100 has a display function, the dopant dosage determination process can be visually displayed on the display interface of the terminal device 100, so that the user can clearly understand the dopant dosage determination process.

[0048] like Figure 1 As shown, the terminal device 100 can communicate with the information input device 200, the measuring unit 300 and the weighing unit 400. The communication method can be wireless communication or wired communication. Wireless communication can be based on networking technologies such as wifi, zigbee, 4G, 5G, etc. Wired communication can achieve communication connection based on data lines or power line carriers. The communication interface can be a standard communication interface. The standard communication interface can be a serial interface or a parallel interface.

[0049] On this basis, the terminal device 100 is used to obtain the information provided by the information input device 200 and the measuring unit 300. The doping amount of the dopant is determined using this information. At the same time, the terminal device 100 can also communicate with the weighing unit 400. At this time, when the terminal device 100 determines the doping amount of the dopant, when weighing the dopant, the weighing unit 400 can be controlled to weigh the dopant according to the doping amount of the dopant, thereby realizing the automatic weighing of the dopant.

[0050] In some examples, such as Figure 1 As shown, the information input device 200 can be a voice input device based on iFlytek voice input, Siri voice input, etc., an electronic pen, a keyboard, etc. The information input device 200 can input some parameters to the terminal device, including but not limited to preset constants, component sizes in a crystal pulling furnace, etc.

[0051] like Figure 1 As shown, the measurement unit 300 can be used to measure radial parameters of a crystal such as a crystal diameter or a crystal radius or detect a pulling speed, and report the measurement result to the terminal device 100. For example, the measurement unit 200 includes a first detection device 301 and a second detection device 302. The first detection device 301 and the second detection device 302 both communicate with the terminal device 100.

[0052] like Figure 1 As shown, the first detection device 301 can detect the radial parameters of the crystal. For example, the first detection device 301 can be an Ircon diameter detection system, a SIMS (Scanned Image Measurement System, abbreviated as SIMS) diameter measurement system, or a CCD (charge coupled device, abbreviated as CCD) camera scanning system. Of course, a detection device based on a binocular vision measurement strategy can also be used.

[0053] like Figure 1 As shown, the second detection device 302 can directly or indirectly detect the crystal pulling speed. The second detection device 202 can be a common speed measuring device such as a speed sensor. For example, a speed meter can collect the speed of the driving motor for pulling the crystal in real time, and convert the speed into the crystal pulling speed, and upload the crystal pulling speed to the terminal device.

[0054] In order to obtain the real-time status of the crystal pulling furnace, the terminal device 100 may also communicate with the industrial computer 500 of the crystal pulling furnace to obtain the status and operation time of the crystal pulling furnace.

[0055] Figure 2 The following is a schematic diagram of the structure of a single crystal furnace. Figure 2As shown, the single crystal furnace 600 is used to pull a melt doped with volatile impurities into a crystal. The material of the crystal can be silicon, germanium, etc., but not limited to this. The volatile impurities can include but are not limited to one or more of gallium, boron, phosphorus, arsenic, and antimony. The impurities mentioned below refer to impurities in the dopant.

[0056] like Figure 2 As shown, the above-mentioned single crystal furnace 600 can be a CZ single crystal furnace, which mainly includes a furnace body 610, a lifting head 620, and a quartz crucible 630, a heating component 640 and a heat preservation barrel 650 respectively located in the furnace body 610. The furnace body 610 is provided with a vacuum interface 611, an inert gas inlet 612, and an exhaust port 613. The heat preservation barrel 650 is arranged at the bottom of the furnace body 610. The heating component 640 and the quartz crucible 630 are arranged in the heat preservation barrel 650. And the quartz crucible 630 can rotate and rise and fall in the heat preservation barrel 650. The lifting head 620 includes a driving motor 621 and a seed crystal shaft 622 arranged on the driving motor 621. The driving motor 621 is arranged at the top of the furnace body 610, and the seed crystal shaft 622 extends from the top of the furnace body 610 into the furnace body 610.

[0057] like Figure 2 As shown, in order to facilitate observation of the situation inside the furnace body 610, the furnace body 610 is also provided with an observation hole 614 for observing the growth of the single crystal inside the furnace body 610. When pulling the crystal, the crystal material containing the dopant can be put into the quartz crucible 630. Under the control of the industrial computer, the heating component 640 melts the quartz crucible 630, so that the crystal material in the quartz crucible 630 is melted to form a melt RT; then the seed crystal Cys is lowered by the pulling head 620, so that the seed crystal Cys contacts the melt. On this basis, the crystal growth processes such as seeding, shoulder release, shoulder rotation, equal diameter growth, and finishing are sequentially experienced to pull the desired single crystal silicon rod.

[0058] For impurities such as gallium, boron, phosphorus, arsenic, and antimony that are easy to volatilize at high temperatures, the gas-liquid phase is in equilibrium during the crystal growth process, and the volatilization of impurities becomes very easy. The volatilization of impurity elements will cause a certain error between the measured resistivity and the target resistivity, thereby affecting the quality of the single crystal. For example, the melting point of gallium is 29.78℃, which is easy to volatilize during the single crystal preparation process, resulting in a certain error between the actual resistivity of the crystal and the target resistivity, thereby affecting the quality of the single crystal.

[0059] In a method for determining a dopant dosage provided in an embodiment of the present invention, the dopant may contain, but is not limited to, one or more elements selected from gallium, boron, phosphorus, arsenic, and antimony. The method for determining a dopant dosage may be executed by a terminal device or by a chip applied to the terminal device. The following embodiment is described by taking the terminal device as an example of the execution subject.

[0060] Figure 3 The process of the method for determining the doping amount of the dopant provided in the embodiment of the present invention is illustrated Figure 1 . Figure 4 Principle for determining the doping amount of dopant provided in the embodiment of the present invention Figure 1 .like Figure 3 and Figure 4 As shown, the method for determining the doping amount of the dopant provided in the embodiment of the present invention includes:

[0061] Step 100: The terminal device determines the target impurity concentration C of the crystal according to the target electrical parameters of the crystal. s The target electrical parameter of the crystal may be any electrical parameter, including but not limited to resistivity, withstand voltage, etc. It should be understood that the impurity here refers to the element that the dopant is finally doped into the crystal. For example, when the dopant is a gallium oxide dopant, the impurity refers to the gallium contained in the gallium oxide.

[0062] In practical applications, the terminal device can set the type of target electrical parameters of the crystal according to the application scenario of the pulled crystal. For example, when the pulled crystal is used in the production scenario of photovoltaic cells, the target electrical parameters of the crystal can be the target resistivity ρ of the crystal. 电 The target resistivity of the crystal is ρ 电 It is pre-stored in the terminal device, or can be input into the terminal device by the information input device. For example, when the target resistivity ρ of the crystal pre-stored in the terminal device 电 If the target resistivity of the crystal to be pulled by the crystal pulling furnace is different from that of the crystal to be pulled, the target resistivity of the crystal to be pulled can be input by using the voice input device. Figure 4 As shown, the target resistivity ρ of the crystal 电 and the crystal target impurity concentration C s The formula 1 is satisfied (refer to GB / T 13389-92):

[0063]

[0064] Based on the above formula 1, when the target resistivity ρ of the crystal is known 电 (that is, the resistivity of the crystal rod head), the crystal target impurity concentration C can be determined according to Formula 1 s For example, the target resistivity of gallium-doped single crystal silicon is 0.5Ω·cm to 4.5Ω·cm, and the target impurity concentration of gallium-doped single crystal silicon can be determined according to Formula 1. For example, when the target resistivity of gallium-doped single crystal silicon is 0.5Ω·cm, the target impurity concentration of gallium-doped single crystal silicon is about 3.26×10 16 Atom / cm 3 .

[0065] Step 200: The terminal device uses the impurity segregation model to process the impurity volatilization parameters and the crystal target impurity concentration C s , obtain the impurity concentration C of the melt at the end of the shoulder L . It should be understood here that the impurity volatilization parameters before equal diameter and the impurity volatilization parameters during the equal diameter stage. These impurity volatilization parameters before equal diameter and the impurity volatilization parameters during the equal diameter stage are design values, and these design values ​​can be used to determine the dopant feed amount of the crystal pulling process that has not yet started. It can be understood that these impurity volatilization parameters before equal diameter and the impurity volatilization parameters during the equal diameter stage can be pre-stored in the terminal device in advance, or can be input into the terminal device through an information input device including but not limited to a voice input device. Of course, if they are pre-stored in the terminal device in advance, if these parameters change, the parameters in the terminal device can also be updated through the information input device.

[0066] In one example, the above-mentioned pre-equal diameter impurity volatilization parameters may include: crystal weight, crucible radial parameters and the time from the end of melting to the end of shoulder turning.

[0067] like Figure 4 As shown in the figure, before the equal diameter stage, the crystal cross section is relatively small and can be ignored. At this time, the crucible radial parameters can be used alone to determine the impurity volatilization area S before the equal diameter stage. L The opening area of ​​the crucible can be considered as the impurity volatilization area S before the equal diameter L .Right now D1 is the diameter of the crucible for holding the melt. It should be understood that the radial parameters of the crucible can be parameters related to the radial dimensions of the crucible, such as the crucible diameter, the crucible radius, and the crucible circumference.

[0068] When the crystal type is determined, such as Figure 4 As shown, the initial volume V0 of the melt can be determined by using the weight of the crystal material and the density of the melt formed after the crystal material is melted. The initial volume V0 of the melt and the time t from the end of the melt to the end of the shoulder are L Based on this, the initial volume of the melt V0 and the time t from the end of the melt to the end of the shoulder can be introduced into the doping amount of the dopant. L For example: Figure 4 As shown, V0=M / ρ 密L , ρ 密L For example, when the crystal material is silicon, the density of silicon liquid is 2.54g / cm 3 .

[0069] In one example, the impurity volatilization parameters in the equal diameter stage include crystal radial parameters and crystal pulling speed.

[0070] like Figure 4As shown in the figure, in the equal diameter stage, the crystal cross section is relatively small. When determining the impurity volatilization area in the equal diameter stage, it is necessary to consider not only the crucible radial parameters but also the influence of the crystal radial parameters. Based on this, the impurity volatilization area S in the equal diameter stage can be determined by using the influence of the crucible radial parameters and the crystal radial parameters. s In other words, the impurity volatilization area S in the equal diameter stage s It can be thought of as the difference between the crucible's open area and the crystal's maximum cross-sectional area. For example: D1 is the crucible diameter of the crystal pulling furnace, and D2 is the diameter of the crystal in the equal diameter process. It can be seen that due to the influence of the already pulled crystal, when determining the first impurity volatilization area, it is necessary to subtract the area occupied by the crystal from the crucible area of ​​the crystal pulling furnace to obtain the impurity volatilization area of ​​the equal diameter process.

[0071] Given that time factors have a significant impact on impurity volatilization, the crystal pulling speed can be used to determine the time required to pull a unit length of crystal. On this basis, ignoring the length of the crystal pulled before equalizing the diameter, the cumulative time for pulling a unit length of crystal is determined, which can also be considered as the first impurity volatilization time t s .like Figure 4 As shown, t s =t L +1 / v,t L is the time from the end of the melt to the end of the shoulder (hereinafter defined as the second impurity volatilization time), and v is the crystal pulling speed. The physical meaning of 1 / v is the time required to pull a 1 cm crystal.

[0072] Since the consumption of molten metal before equalizing the diameter is relatively small, the consumption of silicon liquid before equalizing the diameter can be ignored. Figure 4 As shown, the solidification fraction per unit length x can be determined by using the crystal weight M and the crystal weight per unit length m'. R is the radius of the crystal rod.

[0073] In one example, if Figure 4 As shown, the first impurity segregation model satisfies Formula 2, which is as follows:

[0074]

[0075] k is the impurity segregation coefficient; B is the impurity volatility coefficient. s , S s , V0 has been described in detail in the previous article and will not be introduced here.

[0076] The above k is the impurity segregation coefficient, which is related to the type of impurity. For example, when the dopant is gallium and the impurity is gallium, k = 0.008, The above B is the impurity volatility coefficient, which is 0.2 to 0.9, and its value is related to the process conditions of the crystal pulling furnace, such as the furnace temperature, furnace pressure, and argon gas flow rate. In addition, different impurities have different volatility coefficients. In the embodiment of the present invention, the impurity volatility coefficient satisfies the small volatility coefficient of the silicon rods pulled at the beginning of a single furnace and before the furnace is shut down during the process of pulling a furnace of silicon rods, and the volatility coefficient of the silicon rods at the middle moment of the single furnace is large, that is, the impurity volatility coefficient increases from small to large as the silicon rods are continuously pulled, and the closer to the shutdown stage, the impurity volatility coefficient gradually decreases. In other words, the crystal pulling furnace can pull multiple crystals by continuously pulling crystals. As the number of crystal roots increases, the impurity volatility coefficient corresponding to the crystal changes from small to large, and then from large to small.

[0077] Step 300: The terminal equipment uses the second impurity segregation model to process the impurity volatilization parameters before equal diameter and the impurity concentration C of the melt at the end of the shoulder rotation. L , and obtain the initial impurity concentration C of the melt. Figure 4 As shown, the second impurity segregation model satisfies Formula 3, which is as follows:

[0078]

[0079] In the above formula 3, B and t L , S L , V0 has been described in detail in the previous article and will not be introduced here.

[0080] Step 400: The terminal device determines the doping amount m of the dopant according to the initial impurity concentration C of the melt. c It is understandable that the dopant dosage m c It can be expressed by parameters such as mass and molar amount that can quantify the dopant. If the crystal pulling furnace only pulls one crystal, or if it pulls multiple crystals, but before pulling the crystal, if there is no residual melt in the crucible, and if the crystal material does not contain impurity elements, then the initial impurity concentration C of the melt is related to the dopant feed amount m c The relationship satisfies Formula 4, as follows:

[0081] m c =λCV0 Formula 4

[0082] If the crystal material contains impurity elements, Figure 4 As shown in the figure, the initial impurity concentration C of the melt is related to the dopant dosage m c The relationship satisfies Formula 5, as follows:

[0083] m c =λ(CV0-N o ), Formula 5

[0084] λ is the conversion constant, V0 is the initial volume of the melt, and N0 is the number of impurities in the crystal. When the initial impurity concentration C of the melt is in atoms / cm 3 , CV0 determines the amount of impurities in the melt. For the convenience of measurement, the conversion constant can be defined to convert the amount of impurities in the melt into the weight or molar amount of the dopant in the melt. As for the value of λ, it is determined according to the target of the conversion. For example: when the dopant is gallium, the amount of impurities needs to be converted into the molar amount of the dopant, then λ=10 -23 / 6.023=1.66×10 -24 / mol; For example, when the dopant is gallium, the impurity quantity needs to be converted into the dopant weight, then λ = 69.72×10 -23 / 6.023=1.16×10 -22 g.

[0085] When a crystal pulling furnace continuously pulls multiple crystals, there may be leftover material in the crucible of the crystal pulling furnace before any crystal is pulled, or there may be no material. For example: the terminal device obtains the internal state information of the crucible. Here, a CCD camera scanning system can be used to scan the internal state of the crucible, and the internal state information of the crucible can be uploaded to the terminal device in the form of an image. The terminal device determines whether there is leftover material in the crucible based on the internal state information of the crucible.

[0086] Of course, it is also possible to determine whether there is residual material in the crystal pulling furnace based on actual conditions. For example, when the terminal device determines that the crystal pulling furnace is about to pull the first crystal, it can be confirmed that there is no residual melt in the crucible in the crystal pulling furnace. At this time, if the impurity volatilization parameters before equalizing the diameter of the first crystal, the impurity volatilization parameters in the equalizing stage, and the target electrical parameters of the crystal are known, the doping amount of the dopant in the crystal can be accurately determined by executing steps 100 to 400.

[0087] When the terminal device determines that the crystal pulling furnace has pulled a crystal, there is generally residual melt in the crucible. At this time, in order to calculate the amount of dopant in the crystal material when pulling the next crystal, the pre-equalizing impurity volatilization parameters and the e-diameter stage impurity volatilization parameters of the already pulled crystal can be used to determine the number of impurities contained in the residual melt in the crucible. For the pre-equalizing impurity volatilization parameters of the already pulled crystal and the e-diameter stage impurity volatilization parameters of the already pulled crystal, these pre-equalizing impurity volatilization parameters and the e-diameter stage impurity volatilization parameters can be measured in the specific process and reported to the terminal device by the information input device or related devices.

[0088] For example, Figure 5 The method for determining the doping amount of the dopant provided in the embodiment of the present invention is illustrated as follows Figure 2 . Figure 6Principle for determining the doping amount of dopant provided in the embodiment of the present invention Figure 2 .like Figure 5 and Figure 6 As shown in the figure, when the crystal pulling furnace finishes pulling the n-1th crystal, if there is residual melt in the crucible, according to the initial impurity concentration C of the melt of the nth crystal h Determine the dopant feed amount m of the crystal pulling furnace for pulling the nth crystal ch include:

[0089] Step 500: The terminal device determines the number of impurities N contained in the residual melt in the crucible when the crystal pulling furnace finishes pulling the n-1th crystal according to the impurity volatilization parameters before and after the equal diameter of the crystal pulling furnace. k .

[0090] For the equal-diameter impurity volatilization parameters of the crystal pulling furnace pulling the n-1th crystal, it can refer to the equal-diameter impurity volatilization parameters of the nth crystal, that is, the equal-diameter impurity volatilization parameters listed in step 200, the only difference is that the equal-diameter impurity volatilization parameters listed in step 200 are the equal-diameter impurity volatilization parameters of the nth crystal, not the equal-diameter impurity volatilization parameters of the n-1th crystal. That is to say, the equal-diameter impurity volatilization parameters of the crystal pulling furnace pulling the n-1th crystal include: the initial impurity concentration C of the melt of the crystal pulling furnace pulling the n-1th crystal q , the weight of the crystal material M of the crystal pulling furnace pulling the n-1th crystal q , crucible radial parameters and the time t from the start of melting to the end of shoulder turning when the crystal pulling furnace pulls the n-1th crystal Lq .

[0091] The initial impurity concentration C of the melt of the crystal pulling furnace pulling the n-1th crystal q You can follow steps 100 to 300 to determine C q The radial parameters of the crucible can refer to the relevant description above and are not limited here.

[0092] For the impurity volatilization parameters after the n-1th crystal is pulled by the crystal pulling furnace, the weight of the n-1th crystal m q , radial parameters of the n-1 crystal, crystal pulling speed v of the crystal pulling furnace pulling the n-1 crystal q and the length Q of the n-1th crystal q The radial parameters of the n-1th crystal can refer to the detailed description of the radial parameters of the crystal in the previous text, and are not limited in detail here. Here, the weight m of the n-1th crystal q It can be obtained from the radial parameter of the n-1th crystal and the length Q of the n-1th crystal q Assume that the radial parameter of the n-1th crystal is D2 as mentioned above, then

[0093] Assuming that there is an impurity concentration of residual melt in the crucible, the crystal material of the crystal pulling furnace to pull the nth crystal is M h The amount of crystal material fed to the crystal pulling furnace to pull the nth crystal is m h At this time, if Figure 6 As shown, we can use m h 、m q and M q Determine M h , which can be expressed as M h =M q -m q +m h .

[0094] like Figure 6 As shown, the number of impurities N contained in the residual melt in the crucible can be determined according to the mathematical relationship between the impurity concentration and the impurity quantity according to Formula 6. k .

[0095] N k =V k C lk Formula 6

[0096] V k It can be determined by the weight of the crystal material of the n-1th crystal and the n-1th crystal, such as Figure 6 As shown, V k The expression can be ρ 密L is the melt density.

[0097] C lk V is the impurity concentration of the residual melt in the crucible when the crystal pulling furnace finishes pulling the n-1th crystal, k is the volume of residual melt in the crucible when the crystal pulling furnace finishes pulling the n-1th crystal. lk For example, we can design formula 7 and formula 8 based on the principle of segregation, and use formula 7 and formula 8 to determine C lk , as follows:

[0098] Based on the principle of impurity segregation, such as Figure 6 As shown, the above formula 7 is V q The initial volume of the melt when the crystal pulling furnace pulls the n-1th crystal. B, k refer to the previous definition (B is the impurity volatility coefficient, k is the impurity segregation coefficient), S s is the impurity volatilization area in the equal diameter stage, please refer to the previous definition for details. sq is the time it takes for impurities to volatilize when the crystal pulling furnace pulls the n-1th crystal, t sq =t Lq +Qq / v q .t Lq It is the time from the beginning of the melt to the end of the shoulder when the crystal pulling furnace pulls the n-1th crystal. Of course, t can also be actually measured here. sq . C Lq It is the impurity concentration of the melt at the end of the shoulder when the crystal pulling furnace pulls the n-1th crystal.

[0099] For the already pulled crystal, the initial concentration of impurities in the melt is known. Based on this, Figure 6 As shown, based on the principle of impurity separation and condensation, the above formula eight is At this time, S L is the impurity volatilization area before equal diameter. L The expression and explanation of can be found in the previous text and will not be elaborated here.

[0100] Step 600: The terminal device determines the number of impurities N contained in the residual melt in the crucible when the crystal pulling furnace finishes pulling the n-1th crystal. k , the weight of the crystal material M of the nth crystal pulled by the crystal pulling furnace h The initial impurity concentration C of the melt when the nth crystal is pulled by the crystal pulling furnace h , determine the dopant feed amount m for the crystal pulling furnace to pull the nth crystal ch .

[0101] For example, when the crystal pulling furnace finishes pulling the n-1th crystal, if there is residual melt in the crucible, such as Figure 6 As shown, the initial impurity concentration C of the melt in the crystal pulling furnace pulling the nth crystal h The dopant dosage m of the melt for pulling the nth crystal in the crystal pulling furnace ch The relationship satisfies: m ch =λ(C h V h -N k -N h ), n is an integer greater than or equal to 2, λ is a conversion constant, and the initial impurity concentration C of the melt of the crystal pulling furnace pulling the nth crystal h Please refer to step 100 to step 300 for execution. h N is the number of impurities contained in the crystal material input to the crystal pulling furnace to pull the nth crystal, k V is the number of impurities in the residual melt in the crucible when the crystal pulling furnace finishes pulling the n-1th crystal, h is the initial volume of the melt in the crystal pulling furnace to pull the nth crystal. Figure 6 As shown, according to the mathematical relationship between mass and volume, ρ 密L It is the melt density of the crystal pulling furnace pulling the n-1th crystal.

[0102] In order to clearly describe the method for determining the dopant dosage provided in an embodiment of the present invention, the following describes the process of determining the dopant dosage for continuously pulling two silicon rods in a crystal pulling furnace by taking silicon crystal and gallium as crystal pulling raw materials for the dopant as an example.

[0103] The first step is to determine the target resistivity of the silicon rod to be drawn. The determination method can refer to step 100 and will not be described in detail here.

[0104] The second step is to calculate the weight of dopant required for the first silicon rod. Assume that there are four types of silicon materials for the first silicon rod. The four types of silicon materials are defined as the first silicon material, the second silicon material, the third silicon material and the fourth silicon material.

[0105] For the first silicon material, the weight of the first silicon material is m1, and the resistivity is ρ1. According to Formula 6, the impurity concentration C of the first silicon material can be determined: y1 Specifically, the resistivity ρ1 of the first silicon material is substituted into Formula 6 to obtain C y1 . C y1 The expression is: On this basis, the number of impurities in the first silicon material 2.33 is the density of solid silicon material.

[0106] For the second silicon material, the weight of the second silicon material is m2 and the resistivity is ρ2. According to Formula 6, the impurity concentration C of the second silicon material can be determined: y2 Specifically, the resistivity ρ2 of the second silicon material is substituted into Formula 6 to obtain C y2 . C y2 The expression is: On this basis, the number of impurities in the second silicon material 2.33 is the density of solid silicon material.

[0107] For the third silicon material, the weight of the third silicon material is m3 and the resistivity is ρ3. According to Formula 6, the impurity concentration C of the third silicon material can be determined: y3 Specifically, the resistivity ρ3 of the third silicon material is substituted into Formula 6 to obtain C y3 . C y3 The expression is: On this basis, the number of impurities in the third silicon material 2.33 is the density of solid silicon material.

[0108] For the fourth silicon material, the weight of the fourth silicon material is m4 and the resistivity is ρ3. According to Formula 6, the impurity concentration C of the fourth silicon material can be determined: y4 Specifically, the resistivity ρ4 of the fourth silicon material is substituted into Formula 6 to obtain C y4 . C y4 The expression is: On this basis, the number of impurities in the fourth silicon material 2.33 is the density of solid silicon material.

[0109] Assume that the dopant dosage of the first silicon rod is m c1 , the number of impurities in the dopant to be doped is N c1 , when the dopant is gallium, then N c1 The expression is

[0110] Based on the above calculation, it can be determined that the number of impurities N in the melt of the first silicon rod is g1 The expression N g1 =N y1 +N y2 +N y3 +N y4 +N c1 When the silicon material is melted into a melt, the initial volume of the melt is V = M / 2.54 = (m1 + m2 + m3 + m4 + m c1 ) / 2.54. According to the relationship between liquid volume and concentration, the expression of the initial impurity density C1 of the melt of the first silicon rod can be determined as: C1=2.54N gl / (m1+m2+m3+m4+m c1 ). Here, due to m c1 Compared with the mass of silicon material, this value can be ignored. Based on this, C1=2.54N g / (m1+m2+m3+m4). According to the above steps 200 and 300, the initial impurity concentration C1 of the melt of the first silicon rod can be determined. Based on this, when C1, m1, m2, m3, and m4 are already known, N c1 The expression of N g1 The expression of C1 determines m c1 The expression is as follows:

[0111]

[0112] Step 3: According to m c1 After determining the feed mass of the dopant by the expression, the dopant is added into the silicon material and the silicon rod is pulled by a crystal pulling furnace.

[0113] When drawing the first silicon rod, the dopant is added to the crucible during loading. The specific method is: after the crucible is filled with silicon material, a cavity is formed from the top center of the silicon material downward, and the height of the cavity is 10cm-30cm. The weighed doping amount m c1 In this application, the crystal growth adopts the Czochralski method. For those skilled in the art, this method can also be used in other crystal growth fields, and this application does not limit this.

[0114] Step 4: When the first ingot is pulled and finished, it is found that there is still residual melt in the crucible. Assuming that when the second silicon ingot is pulled, the silicon material is still added in the same way as the first ingot, the number of impurities in the residual melt in the crucible is N. k1 At this time, if there is no volatilization of impurities, the number of impurities in the silicon material of the second crystal rod is N g2 The expression N g2 =N y1 +N y2 +N y3 +N y4 +N k1 +N c2 When the crystal material in the crucible begins to melt, the amount of impurities volatilized needs to be considered. At this time, N can be determined according to formulas 6 to 8. k1 It should be understood that in the process of determining the relevant parameters of the second silicon rod, the impurity volatilization parameter used is different from the impurity volatilization parameter used to calculate the dopant feed amount of the first silicon rod.

[0115] On this basis, according to step 200 and step 300, the initial impurity concentration C2 of the melt of the second silicon rod can be determined. Referring to the derivation process of the second step, the dopant feed amount m of the second silicon rod is determined. c2 The expression is as follows:

[0116] Here m k1 is the weight of the residual melt in the crucible, which can be obtained by subtracting the weight of the first crystal rod from the weight of the crystal material of the first crystal rod.

[0117] Step 5: According to the calculation in step 4, the dopant dosage m of the second silicon rod is c2 Dopants are added to the silicon material, and the second silicon rod is pulled. At this time, the residual melt in the crucible of the first silicon rod is used as part of the raw material of the second crystal material and participates in the pulling of the second silicon rod.

[0118] In practical applications, the dopant of the second silicon rod can be placed in a feeding tube and added to the crucible along with the silicon material to grow a single crystal by the Czochralski method. Of course, other methods can also be used to grow single crystals, which will not be introduced here.

[0119] In the sixth step, when the second silicon rod is pulled and finished, it is found that there is still residual melt in the crucible. At this time, after the silicon rod is pulled out of the crystal pulling furnace, the dopant dosage of the third crystal rod is determined according to the relevant parameters of the second crystal rod that has been pulled and the relevant parameters of the third crystal rod to be pulled according to the fourth step. If more silicon rods need to be pulled, the operation of the third step can still be referred to, but the required parameters will change according to the different crystals pulled until the crystal pulling furnace is stopped.

[0120] As can be seen from the above, when the target electrical parameters of the crystal are known to determine the target impurity concentration C of the crystal s In the case of the first impurity segregation model, the impurity volatilization parameters before equal diameter, the impurity volatilization parameters at the equal diameter stage and the crystal target impurity concentration C s , the impurity concentration C of the melt at the end of the shoulder can be obtained L On this basis, the second impurity segregation model is used to process the impurity volatilization parameters before equal diameter and the impurity concentration C of the melt at the end of shoulder turning. L , and obtain the impurity concentration C of the melt at the end of the melting. At this time, the doping amount m of the dopant determined according to the impurity concentration C of the melt at the end of the melting c Then, according to the dopant dosage m c Adding dopants to the crystal material can ensure that there is basically no deviation between the actual electrical parameters (such as resistivity) of the crystal finally pulled by the crystal pulling furnace and the target electrical parameters (such as target resistivity), thereby improving the quality of the single crystal.

[0121] In practical applications, the method for determining the doping amount of the dopant provided in the embodiment of the present invention combines the impurity volatilization characteristics of the dopant with the segregation principle in the process of calculating the corresponding dopant weight according to the target resistivity of the silicon rod, and combines the change in the amount of impurities in the crucible before and after volatilization. According to the target resistivity of the silicon rod, the amount of dopant required for drawing the silicon rod is accurately calculated, thereby greatly improving the quality and yield of the silicon rod products.

[0122] The above mainly introduces the solution provided by the embodiment of the present invention from the perspective of the terminal device. It is understandable that in order to realize the above functions, the terminal device includes a hardware structure and / or software module corresponding to each function. Those skilled in the art should easily realize that, in combination with the units and algorithm steps of each example described in the embodiments disclosed in this article, the present invention can be implemented in the form of hardware or a combination of hardware and computer software. Whether a function is executed in the form of hardware or computer software driving hardware depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to exceed the scope of the present invention.

[0123] The embodiment of the present invention can divide the terminal device etc. into functional modules according to the above method example. For example, each functional module can be divided according to each function, or two or more functions can be integrated into one processing module. The above integrated module can be implemented in the form of hardware or in the form of software functional modules. It should be noted that the division of modules in the embodiment of the present invention is schematic and is only a logical function division. There may be other division methods in actual implementation.

[0124] In the case of using the corresponding integrated unit, Figure 7 FIG. 2 is a block diagram showing a device for determining the doping amount of a dopant provided by an embodiment of the present invention. Figure 7 As shown, the dopant dosage determining device 700 may be Figure 1 The terminal device 100 shown includes: a processing unit 701.

[0125] like Figure 7 As shown, the processing unit 701 is used to support the steps 100 to 400 of the method for determining the doping amount executed by the terminal device.

[0126] In some possible implementations, such as Figure 7 As shown, the processing unit 701 is used to support the steps 500 and 600 of the method for determining the doping amount executed by the terminal device.

[0127] In some possible implementations, such as Figure 7 As shown, the dopant dosage determination device 700 may further include a storage unit 702 for storing program codes and data, which may be various parameters in the above embodiments.

[0128] In some possible implementations, such as Figure 7 As shown, the dopant dosage determination device 700 may further include a communication unit 703 for communicating with an industrial computer, a measuring unit and an information input device to obtain external parameters.

[0129] Among them, Figure 7As shown, the processing unit 701 can be a processor or a controller, for example, a central processing unit (CPU), a general processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic devices, transistor logic devices, hardware components or any combination thereof. It can implement or execute various exemplary logic blocks, modules and circuits described in conjunction with the disclosure of the present invention. The processor can also be a combination that implements a computing function, such as a combination of one or more microprocessors, a combination of a DSP and a microprocessor, and the like. The communication unit 703 can be a transceiver, a transceiver circuit or a communication interface, and the like. The storage unit 702 can be a memory.

[0130] like Figure 7 As shown, when the processing unit 701 is a processor, the communication unit 703 is a transceiver, and the storage unit 702 is a memory, the dopant dosage determination device involved in the embodiment of the present invention can be Figure 6 The electronic equipment shown.

[0131] Figure 8 FIG. 1 is a schematic diagram showing the hardware structure of an electronic device provided by an embodiment of the present invention. Figure 8 As shown, the electronic device 800 includes a processor 810 .

[0132] like Figure 8 As shown, the processor 810 may be a general-purpose central processing unit (CPU), a microprocessor, an application-specific integrated circuit (ASIC), or one or more integrated circuits for controlling the execution of the program of the present invention.

[0133] like Figure 8 As shown, the electronic device 800 may further include a communication line 840. The communication line 840 may include a path for transmitting information between the above components.

[0134] Optional, such as Figure 8 As shown, the electronic device may further include a communication interface 820. There may be one or more communication interfaces 820. The communication interface 820 may use any transceiver or other device for communicating with other devices or communication networks.

[0135] Optional, such as Figure 8 As shown, the electronic device may further include a memory 830. The memory 830 is used to store computer-executable instructions for executing the solution of the present invention, and is controlled to execute by a processor. The processor is used to execute the computer-executable instructions stored in the memory, thereby implementing the method provided by the embodiment of the present invention.

[0136] like Figure 8 As shown, the memory 830 may be a read-only memory (ROM) or other types of static storage devices that can store static information and instructions, a random access memory (RAM) or other types of dynamic storage devices that can store information and instructions, or an electrically erasable programmable read-only memory (EEPROM), a compact disc read-only memory (CD-ROM) or other optical disc storage, optical disc storage (including compressed optical disc, laser disc, optical disc, digital versatile disc, Blu-ray disc, etc.), a magnetic disk storage medium or other magnetic storage device, or any other medium that can be used to carry or store the desired program code in the form of instructions or data structures and can be accessed by a computer, but is not limited thereto. The memory 830 may exist independently and be connected to the processor 810 via a communication line 840. The memory 830 may also be integrated with the processor 810.

[0137] Optionally, the computer-executable instructions in the embodiment of the present invention may also be referred to as application program codes, which is not specifically limited in the embodiment of the present invention.

[0138] In a specific implementation, as an example, Figure 8 As shown, the processor 810 may include one or more CPUs, such as Figure 8 CPU0 and CPU1 in.

[0139] In a specific implementation, as an example, Figure 8 As shown, the terminal device may include multiple processors, such as Figure 8 The processor 810 and the processor 850 in the embodiment of the present invention are shown in FIG. Each of these processors may be a single-core processor or a multi-core processor.

[0140] Fig. 9 Schematic diagram of the structure of the chip provided by the embodiment of the present invention. Fig. 9 As shown, the chip 900 includes one or more (including two) processors 910 .

[0141] Optional, such as Fig. 9 As shown, the chip also includes a communication interface 920 and a memory 930. The memory 930 may include a read-only memory and a random access memory, and provide operation instructions and data to the processor. A portion of the memory may also include a non-volatile random access memory (NVRAM).

[0142] In some embodiments, Fig. 9 As shown, the memory 930 stores the following elements, execution modules or data structures, or their subsets, or their extended sets.

[0143] In the embodiment of the present invention, Fig. 9 As shown, the corresponding operation is performed by calling the operation instruction stored in the memory (the operation instruction may be stored in the operating system).

[0144] like Fig. 9 As shown, the processor 910 controls the processing operations of any one of the terminal devices, and the processor 910 can also be called a central processing unit (CPU).

[0145] like Fig. 9 As shown, the memory 930 may include a read-only memory and a random access memory, and provide instructions and data to the processor. A portion of the memory 930 may also include an NVRAM. For example, in an application, the memory, the communication interface, and the memory are coupled together through a bus system, wherein the bus system may include a power bus, a control bus, and a status signal bus in addition to a data bus. However, for the sake of clarity, in Fig. 9 Various buses are labeled as bus system 940 .

[0146] like Fig. 9As shown, the method disclosed in the above embodiment of the present invention can be applied to a processor or implemented by a processor. The processor may be an integrated circuit chip with signal processing capabilities. In the implementation process, each step of the above method can be completed by an integrated logic circuit of hardware in the processor or an instruction in the form of software. The above processor may be a general-purpose processor, a digital signal processor (digital signal processing, DSP), an ASIC, a field-programmable gate array (field-programmable gate array, FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components. The methods, steps and logic block diagrams disclosed in the embodiments of the present invention can be implemented or executed. The general-purpose processor may be a microprocessor or the processor may also be any conventional processor, etc. The steps of the method disclosed in the embodiment of the present invention can be directly embodied as being executed by a hardware decoding processor, or executed by a combination of hardware and software modules in the decoding processor. The software module may be located in a mature storage medium in the field such as a random access memory, a flash memory, a read-only memory, a programmable read-only memory or an electrically erasable programmable memory, a register, etc. The storage medium is located in a memory, and the processor reads the information in the memory and completes the steps of the above method in combination with its hardware.

[0147] On the one hand, a computer-readable storage medium is provided, in which instructions are stored. When the instructions are executed, the functions performed by the terminal device in the above embodiment are implemented.

[0148] On the one hand, a chip is provided, which is applied to a terminal device. The chip includes at least one processor and a communication interface. The communication interface is coupled to at least one processor, and the processor is used to run instructions to implement the functions performed by... in the above embodiments.

[0149] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented by software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer programs or instructions. When the computer program or instruction is loaded and executed on a computer, the process or function described in the embodiment of the present invention is executed in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, a terminal, a user device or other programmable device. The computer program or instruction can be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer program or instruction can be transmitted from one website site, computer, server or data center to another website site, computer, server or data center by wired or wireless means. The computer-readable storage medium can be any available medium that can be accessed by a computer or a data storage device such as a server, data center, etc. that integrates one or more available media. The available medium can be a magnetic medium, such as a floppy disk, a hard disk, or a tape; it can also be an optical medium, such as a digital video disc (DVD); it can also be a semiconductor medium, such as a solid state drive (SSD).

[0150] Although the present invention is described herein in conjunction with various embodiments, in the process of implementing the claimed invention, those skilled in the art may understand and implement other variations of the disclosed embodiments by viewing the drawings, the disclosure, and the appended claims. In the claims, the word "comprising" does not exclude other components or steps, and "one" or "an" does not exclude multiple situations. A single processor or other unit may implement several functions listed in the claims. Certain measures are recorded in different dependent claims, but this does not mean that these measures cannot be combined to produce good results.

[0151] Although the present invention has been described in conjunction with specific features and embodiments thereof, it is apparent that various modifications and combinations may be made thereto without departing from the spirit and scope of the present invention. Accordingly, this specification and the accompanying drawings are merely exemplary illustrations of the present invention as defined by the appended claims and are deemed to cover any and all modifications, variations, combinations or equivalents within the scope of the present invention. Obviously, those skilled in the art may make various modifications and variations to the present invention without departing from the spirit and scope of the present invention. Thus, the present invention is intended to include such modifications and variations if they fall within the scope of the claims of the present invention and their equivalents.

Claims

1. A method for determining the dosage of a dopant, characterized in that: Applied to a crystal pulling furnace, the crystal pulling furnace is used to pull a melt doped with volatile impurities into a crystal; the method for determining the feeding amount of the dopant includes: Determine the crystal target impurity concentration C based on the crystal's target electrical parameters s ; The first impurity segregation model is used to process the impurity volatilization parameters before equal diameter, the impurity volatilization parameters of the equal diameter stage and the crystal target impurity concentration C s , obtain the impurity concentration C of the melt at the end of the shoulder L ; Wherein, the impurity volatilization parameters before equal diameter include: crystal weight, crucible radial parameters and the time from the end of melting to the end of shoulder turning; and / or the impurity volatilization parameters in the equal diameter stage include: crystal radial parameters and crystal pulling speed; the first impurity segregation model satisfies: Where k is the impurity segregation coefficient; x is the crystal solidification fraction per unit length; B is the impurity volatility coefficient; t s is the volatilization time of the first impurity, t s =t L +1 / v,t L is the time from the end of the melt to the end of the shoulder, v is the crystal pulling speed, S s is the impurity volatilization area in the equal diameter stage, D1 is the crucible diameter of the crystal pulling furnace, D2 is the diameter of the crystal in the isodiameter process, and V0 is the initial volume of the melt; The second impurity segregation model is used to process the impurity volatilization parameters before the equal diameter and the impurity concentration C of the melt at the end of the shoulder rotation. L , obtain the initial impurity concentration C of the melt; the second impurity segregation model satisfies: Where B is the impurity volatility coefficient, t L S is the time from the end of melting to the end of shoulder turning, L is the impurity volatilization area before equal diameter, D1 is the diameter of the crucible used to hold the melt, V0 is the initial volume of the melt, V0 = M / ρ 密L , 密L is the melt density; Determine the dopant dosage m according to the initial impurity concentration C of the melt. c .

2. The method for determining the doping amount of the dopant according to claim 1, characterized in that: The target electrical parameter of the crystal is the target resistivity ρ of the crystal 电 ; The target resistivity of the crystal ρ 电 With the crystal target impurity concentration C s Satisfy between:

3. The method for determining the doping amount of a dopant according to any one of claims 1 to 2, characterized in that: When there is no residual material in the crucible of the crystal pulling furnace, the initial impurity concentration C of the melt and the feeding amount m of the dopant c The relationship satisfies: m c =λ(CV0-N0), λ is the conversion constant, V0 is the initial volume of the melt, and N0 is the number of impurities contained in the crystal material.

4. The method for determining the doping amount of a dopant according to any one of claims 1 to 3, characterized in that: The crystal pulling furnace is used to pull multiple crystals. When the crystal pulling furnace finishes pulling the n-1th crystal, if there is residual melt in the crucible, according to the initial impurity concentration C of the melt of the nth crystal, h Determine the dopant feed amount m of the crystal pulling furnace for pulling the nth crystal ch include: According to the impurity volatilization parameters before equalizing the diameter of the n-1 crystal pulled by the crystal pulling furnace and the impurity volatilization parameters during the equalizing stage, the number of impurities N contained in the residual melt in the crucible when the crystal pulling furnace finishes pulling the n-1 crystal is determined. k , including using the formula: N k =V k C lk Calculate N k Among them, C lk is the impurity concentration of the residual melt in the crucible when the crystal pulling furnace finishes pulling the n-1th crystal, V k is the volume of the residual melt in the crucible when the crystal pulling furnace finishes pulling the n-1th crystal; M q is the weight of the n-1th crystal, m q is the weight of the n-1th crystal, ρ 密L is the melt density; When the crystal pulling furnace pulls the n-1th crystal, the number of impurities N contained in the residual melt in the crucible is k , the weight M of the crystal material of the nth crystal pulled by the crystal pulling furnace h and the initial impurity concentration C of the melt of the crystal pulling furnace pulling the nth crystal h , determine the dopant feed amount m of the crystal pulling furnace for pulling the nth crystal ch ; including the use of the formula: m ch =λ(C h V h -N k -N h ) Calculate m ch ; Where n is an integer greater than or equal to 2, λ is a conversion constant, N h is the number of impurities contained in the crystal material input into the crystal pulling furnace to pull the nth crystal, V h is the initial volume of the melt for pulling the nth crystal in the crystal pulling furnace, N k It is the number of impurities contained in the residual melt in the crucible when the crystal pulling furnace finishes pulling the n-1th crystal.

5. The method for determining the doping amount of the dopant according to claim 4, characterized in that: The impurity volatilization parameters before the equal diameter of the n-1 crystal pulled by the crystal pulling furnace include: the initial impurity concentration C of the melt of the n-1 crystal pulled by the crystal pulling furnace q , the weight M of the crystal material of the n-1th crystal pulled by the crystal pulling furnace q , the time t from the start of melting to the end of shoulder turning when the crystal pulling furnace pulls the n-1th crystal Lq , and crucible radial parameters; and / or, The impurity volatilization parameters of the equal diameter stage of the crystal pulling furnace pulling the n-1th crystal include the crystal radial parameters, the crystal pulling speed and the length Q of the n-1th crystal. q .

6. The method for determining the doping amount of the dopant according to claim 4, characterized in that: C Lq is the impurity concentration of the melt at the end of shoulder rotation when the crystal pulling furnace pulls the n-1th crystal; C q The initial impurity concentration of the melt when the crystal pulling furnace pulls the n-1th crystal; k is the impurity segregation coefficient, B is the impurity volatility coefficient; S L is the impurity volatilization area before equal diameter, S s is the impurity volatilization area in the equal diameter stage, V q is the initial volume of the melt when the crystal pulling furnace pulls the n-1th crystal; t sq is the time for impurities to volatilize when the crystal pulling furnace pulls the n-1th crystal, t sq =t Lq +Q q / v q ;t Lq v is the time from the start of melting to the end of shoulder turning when the crystal pulling furnace pulls the n-1th crystal, q is the crystal pulling speed in the equal diameter process when the crystal pulling furnace pulls the n-1th crystal, Q q is the length of the n-1th crystal.

7. A device for determining the amount of dopant, characterized in that: include: A processor and a communication interface coupled to the processor; the processor is used to run a computer program or instruction to implement the method for determining the doping amount of a dopant according to any one of claims 1 to 6.

8. A computer storage medium, characterized in that: The computer storage medium stores instructions, and when the instructions are executed, the method for determining the doping amount of the dopant according to any one of claims 1 to 6 is implemented.

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