TW446764B - Formation method of single crystal, single crystal formed by using the same, and single crystal wafer - Google Patents

Abstract

In order to reduce the density of grown-in defects within a single crystal by controlling the diameter of a ring stacking fault, the present invention relates to a single crystal growing method wherein a single crystal is grown by pulling a seed crystal after dipping the seed crystal into a melt within a crucible, comprising the steps of previously obtaining a pulling speed Vop so that a crystal deformation rate expressed by (maximum diameter CMAX-minimum diameter DMIN)/minimum diameter DMIN in a crystal plane 1 orthogonal to the crystal pulling direction is within the range of 1.5-2.0% and pulling a single crystal where a target pulling speed V during the actual single crystal growth is set to be V=VOP X Α (Α ≤ 0.8).

Description

今 _4 6 ~? _6 4- Announcement The description of the invention of this jade Fei χ- invention scope The present invention relates to a single crystal breeding method. The single crystal and single crystal wafers bred using the method are more specifically related to A single crystal breeding method for cultivating a single crystal of Shi Xi single crystal with a small defect density used as a semiconductor material-a single crystal and a single crystal wafer σ produced by this method. [Description of known technology] Silicon single crystal t formed by Czochralski method (hereinafter abbreviated as CZ method) is usually produced as infrared scattered particles (c0 (crystal originated particle), FPD (Flow Pattern Defect)) and defects called dislocation clusters. These defects are not newly formed in the crystal during the heat treatment of the subsequent device manufacturing process, but have been formed in the crystal pull. Also known as a grow-in defect. Figure 1 is a schematic diagram showing the general relationship between the pull-up speed and the location of crystal defect generation during the growth of a single crystal. As shown in FIG. 1, inside the multilayer defect ring (R-0SF) 22, which has a heat-induced induced defect (〇SF: 〇xidation ~ induced Stacking Fault), a crystal is detected. Infrared scattered body 21, which is a kind of inner-length defect, is observed during the evaluation after incubation, and a kind of inner-length defect is detected as a misalignment outside the laminated defect ring (R-OSF) 22 described above. Defects of the line group 24 have a defect area 23 near the layer defect ring (R-OSF) 22 outside. The diameter D of the inner long defect ring in the figure is generated by the infrared scattered body 21 detected inside the laminated defect ring 22

Page 4 446 764 V. Description of the invention (2) The diameter of the area is shown. In addition, the generation field of the laminated defect ring 22 is related to the pulling speed during the growth of the single crystal. The smaller the pulling speed, the more the area of the accumulated defect ring 22 decreases from the outside of the crystal toward the inside. · Details about the aforementioned common sense are described in Defect Control in Semiconductor (Elsevier Science Publishers B. V. (1 990) ′ M. Hasebe etc. p.157). Recently, with the use of low temperature in the manufacturing process of semiconductor devices and the low oxidation with the growth of single crystals, it has been possible to suppress oxidation-induced build-up defects that adversely affect the device, which is caused by the aforementioned build-up defects The deterioration of the device has now become a state where no major problems are brewing. In contrast, the internal length defect existing on the inner side of the aforementioned laminated defect ring 22 is due to the integrity of the gate oxide film (G〇I (Gate 〇xide

Integrity)) has adversely affected, so recently, a method to reduce the density of the aforementioned internal defects in a single crystal has become a very important issue, and a method of this kind has been proposed. For example, Japanese Unexamined Patent Publication No. 9-202690 (Document 丨) discloses a method of "bringing a single crystal at a drawing speed of 80% to 60% with respect to the limit drawing speed Vm inherent to the drawing device". In addition, Japanese Unexamined Patent Publication No. 7 257991 (Document 2) states that "By cultivating a single crystal at a maximum pulling speed" J degree VMAX (= f XG), a ring without laminated defects can be obtained. Single crystal wafers (f: proportionality factor, G: axial temperature gradient) These conventional techniques can be used without reducing the single crystal production efficiency.

Page 5 446764 V. Description of the invention (3) (that is, without greatly reducing the pulling speed of the single crystal), reducing the diameter of the aforementioned laminated defect ring depending on the pulling speed, and attempting to make effective use of the Defect-free area outside the ring. The main content of the technologies described in Documents 1 and 2 is that a single crystal is bred at a pull-up speed ν (= ν · χ0.6 · 0 to 8 (Reference 1)) below a limit pull-out speed VMAX. . The growth rate Vgr of a single crystal can be simply expressed by the following formula 1.

Vgr = l / L P [Ks (dT / dx) s-KL (dT / dx) L] (1)

Ver: Growth rate L: Heat of solidification P: Crystal density

Ks: thermal conductivity of crystal (dT / dx) s: temperature gradient in crystal KL: thermal conductivity of molten liquid (dT / dx) L: temperature gradient in the molten liquid due to the limit pulling speed VMAX means that no Seepage heat, so the heat transfer items from the melt in Equation I can be removed and expressed by Equation 2 below. = 1 / L p [Ks (dT / dx) s] (2) As can be seen from the above formula 2, and as disclosed in reference 2, to obtain the limit pulling speed VMAX 'is the temperature in the crystal The value of the gradient. On the other hand, if the value of the temperature gradient is unknown, the value of the limit pull-up speed VMAX cannot be obtained. However, the value of the aforementioned temperature gradient varies with the crystallization.

Page 6 446764 V. Description of the invention (4) = The residual position of the raw material molten liquid or the relative position of the crucible filled with the molten liquid and the heater is constantly changing. Therefore, even if it depends on experience, Its value is also very solid. And in the actual crystallization incubation step, there is no ideal limit pull-out speed represented by the above formula 2 and ^ ', because ... the mechanical offset between the rotation axis and the crucible rotation axis, Various factors, such as the offset between the center of f and the center of heat distribution, and the inclination of the horizontal angle of the single crystal, can be obtained even if the crystal is drawn at the speed Vi (< Vmax) of the ultimate pulling speed Vmax above J =. Hair crystals are twisted into a spiral, which makes it impossible to continue crystallization. *, Because the operator often regards the pull speed when it is unable to continue as the limit pull speed vMx (actually the limit pull beyond the observed value ^ vri degree L will be difficult to define the true limit based on the operator's instinct : In addition to the above-mentioned deviation of the crystal rotation axis and the crucible rotation axis, the tilt of the single crystal incubation device with respect to the horizontal angle between the rotation center and the heat distribution center in the crystal, etc., including the crystallization incubator meat and the factors 'When different graphite structures are formed, the ultimate pull-up speed will be changed. Therefore, it is difficult to determine the inherent limit of each single crystal growth and growth device. It is difficult to determine what is described in Document 1. "Single said that the limit and pull-out speed v inherent in the ancient and device is practical. It is impossible to implement AX [it even if the conventional technology described in Document 1 or 2 is adopted, it is practically It is impossible to control the JL diameter of the aforementioned laminated defect ring 22, and it is very difficult to reduce the single 446764. V. Description of the invention (5)-The density of the internal defect on the inside of the aforementioned laminated defect ring 2 in the crystal is very difficult. [Development] The present invention has been developed in view of the above-mentioned problems, and its purpose is to provide a method for cultivating single crystals, which can reduce the density of internal defects in single crystals by controlling the diameter of the lacking ring in the laminate. Provide—The existence rate of long-type defects is extremely small for single crystals and single crystal wafers. When the pull speed of the single crystal is close to the true limit pull speed ^, that is, when 3iL ( When the term of dT / dX) L is close to ^, the shape of the surface perpendicular to the crystal pulling direction in the moon is deformed into a shape other than true circle = shape. The second figure is to reveal that it is perpendicular to the crystal pulling direction In the schematic diagram of the cut surface 1 of the single crystal, when the single crystal being pulled grows without dislocation, as shown in the figure, four parts on the outer peripheral surface 2 of the single crystal being pulled will appear. The shape of the protrusion extending parallel to the pulling direction: the crystalline inertia line 2a, and the dependence of the growth rate on the crystalline orientation & the shape of the single crystal cut surface 1 can be changed from the true circle shape Four shapes. DMAX and DMIN are single crystals The largest diameter and the smallest straight hair are all focused on the shape of the cut surface deformed from the true circle shape into the crystal of other history, and various experiments and analysis are carried out. The result of this inspection and analysis is that the foregoing is found. Deformation rate of single crystal cut surface, round shape, and deformation rate starting from ^ 1 shape (hereinafter referred to as crystal deformation straight 々 'η' — within the plane of the ancient crystal pulling direction perpendicularly intersecting the surface (maximum diameter MAX & Dmin) / Minimum diameter DM1N and diameter of laminated defect ring

446764 Fifth, the invention description (6), there is a clear relationship. From this, '^-"The third picture can be the diameter of the defect ring of the stacking layer before uncovering.' The fixed crystal deformation rate is the white circle and the black triangle pair. It is obtained that the relationship between the black circle and the white circle C is from The crystals obtained from the 8-hour crystal are 'black circles, black triangles, and white four corners;': The incubation system of the breeding device includes crystalline = internal :: which means that single crystals produce different crystals. 30% of the graphite structures in the furnace, called the hot zone, are marked with "X" in the white box, because of the "corner column shape or polygonal column shape, and the cylindrical method continues," and the white box There is a "χ" record = crystals are grown without crystals to produce a spiral distortion, = because of the situation. The data shown in Figure 3 when yttrium is not allowed to continue is about the central part from the length of the crystal (about 400mm to 6001111 from the top of the crystal straight body). Location). As apparent from Fig. 3, when the crystal deformation rate is 1, 5 or more, it is almost independent of the crystal diameter or the single crystal incubation device. The diameter of the laminated defect ring is located on the outermost periphery of the single crystal being pulled. Also, although not shown, the relationship between the crystal deformation rate and the diameter of the laminated defect ring can also be established at the top and bottom of the single crystal being pulled. Fig. 4 is the relationship between the crystal deformation rate of the samples shown in Fig. 3 and the pulling speed of these samples during incubation. As can be seen from Figures 3 and 4,

Page 9 4 46 7 6 4 · V. Description of the invention (that is, ^ = means that the limit of the pull-out speed at which crystal growth cannot continue is above ΐ, and it is not possible to directly determine the single crystal superposition layer. The placement of defect rings. However, if the crystal deformation rate is more than 5%, it has nothing to do with the difference between the crystal two = early crystallization incubation device. The laminated defect ring will be located at the outermost periphery of the @ 地 单晶. The crystal deformation rate is an index. When the ring is located on the outer periphery of the single crystal being pulled, the pulling speed, and the coefficient of mi, ^, the ring crystals with the desired laminated defects can be obtained. Also, when the crystal deformation rate is When it exceeds 20%, the surface shape that is orthogonal to the crystal is straight. The concave Λ will be too serious, which will increase the loss of the round cutting process that is adopted to select a straight branch. Therefore, the speed of the pull is determined as It is not ideal to make the crystal deformation rate exceed the value of 2.0%. Purely, according to the above investigation, the approximate value of the crystal pulling speed is set in advance from the top to the bottom of the lifting direction to make the deformation rate. Can be in the range of ▲ 'Ο X, then by the length of each crystal The pair of direction and position = the approximate value of the pulling speed of the two crystals is multiplied by a fixed coefficient, and a single crystal having the desired diameter of the laminated defect ring can be obtained throughout the single crystal. &Amp; The single crystal breeding method (1) related to the invention is that the seed is crystallized by pulling the seed to crystallize after the seed is crushed in the melt in the crucible. In the vertical direction of the lifting direction, (maximum diameter-minimum diameter) / minimum diameter " indicates that the 3 shape rate can be in the range of 15 to 2.0% of the pulling speed ν0P ', and 2 times the goal of the month The pulling speed v is set to ν = νχ. According to the above-mentioned single crystal breeding method (1), the crystal deformation rate is adjusted by

Page 10 446764 V. Description of the invention (8) The pulling speed v0p within the range of appropriate value (1.5 to 2.0%), multiplied by the-& coefficient α ($ 〇.8), the laminated defect ring The diameter is set to the desired value. Therefore, by reducing the diameter of the laminated defect ring, a defect-free region existing outside the laminated defect ring can be used. "The single crystal growing method (2) according to the present invention is to calculate in advance in the plane perpendicular to the crystal pulling direction in the crystal growing method (1) above" (maximum diameter-minimum diameter) / The "minimum diameter" indicates that the knot deformation rate can be within a range of 1.5 to 2.0% of the pulling speed ν〇ρ, and the actual pulling target speed V at the time of growing from V = X = (0.3 each cold $ 1〇) is calculated, and the measurement uses at least two level coefficients, the aforementioned ^ standard drawing speed of fire, the diameter of the long defect ring in each crystal ^^, and then from From the measurement results, the rate of change of the diameter of the inner-long defect ring (10,000 to 2) is calculated, and based on the calculation result, the coefficient α, which is set by setting the diameter of the inner-long defect ring to a desired value, is used as its characteristic. According to the above-mentioned single crystal breeding method (2), by using the aforementioned diameter change rate of the inner-length defect ring obtained from each single crystal bred by using at least two level coefficients 3 and 2, the single crystal can be spread throughout the single crystal. For the total length, the diameter of the inner-long defect ring is correctly set to a desired value.

Also, the method (3) for cultivating single crystals according to the present invention is to control the pull-up speed during actual culturing in the above-mentioned methods for cultivating single crystals (1) and (2), in a range of Vr = V ± 0.4V. Within the range, the average pulling speed Vac within a certain period of time from the start of the single crystal pulling is controlled within a range of vac = v ± 0.02V, which is a feature of the characteristic. The method (3) for growing a single crystal is described above.

Page 11 446764 V. Description of the invention (9) '' " 'The range of the actual pull speed is controlled within a proper range, and the average pull and the degree are also controlled within a proper range. The crystal production efficiency < in the case of " suppresses the variation of the diameter of the laminated defect ring. Furthermore, the method (4) for growing a single crystal according to the present invention is characterized in that the coefficient α is 0.6 or less in any one of the above-mentioned methods (1) to (3) for forming single crystals. The above-mentioned single crystal breeding method (4), by growing the single crystal by setting the coefficient α to 0.6 or less, the number of particles that can be fermented to be substantially zero is calculated. B— ° The invention also has a The single crystal (1) is a type of single crystal, which is a single crystal that has been produced by any one of the methods of single crystal moon formation (丨) to (4), and is characterized in that the internal long defect is 0 to 2 The low density of xl0Vcin3, and the internal defects are evenly distributed over the full length of the single crystal. / The above-mentioned single crystal (1) 'The internal long defects are low-density, and the internal long defects are uniformly distributed over the entire length of the single crystal. Larger single crystals can be obtained in 4 parts which are preferable as a semiconductor material. Also, the single crystal wafer (丨) related to the present invention is one of two: i formed by any one of the above two methods of single crystal incubation (i) to (3) i: 2: cut I and then apply mirror polishing, etc. It is characterized by counting the number of particles with a size of 0 · 13 μ or more implemented by the H surface inspection machine. Ϊ Λ is 25 or less at the time of the wafer, and 50 at the time of the 8-inch wafer. For a 12-inch wafer, it is 100 or less. Based on the above-mentioned single crystal wafer (1), a high-quality semiconductor device with a small number of particles and excellent characteristics as described above can be manufactured. Number of child poles 446764 V. Description of the invention (10) and 'Single-crystal wafer related to the present invention (2)' It is a single-crystal wafer 'is a single crystal which is bred using the aforementioned single-crystal growing method (4) It is made by slicing and performing mirror polishing, and is characterized in that the count value of particles with a size of 0.13 or more performed by a laser surface inspection machine is substantially zero. In the single crystal wafer (2), since the count of the particles is substantially zero ', a high-quality semiconductor device having excellent characteristics can be produced. [Detailed description of the invention] Hereinafter, an embodiment of the method for growing a single crystal according to the present invention will be described with reference to the drawings. Fig. 5 is a cross-sectional view showing an example of a single crystal incubation device used in the CZ method, and Fig. 11 shows a crucible. This sweet evil 11 is composed of a bottomed cylindrical quartz crucible 11a and a graphite bottomed cylindrical graphite 11b fitted on the outer side of this quartz hanging mat 11a. It is supported on a support shaft 18 that rotates at a constant speed in the direction of arrow a in the figure. On the outer side of the crucible, a resistance heating heater 12 is arranged, and on the outer side of the heater, a heat-preserving cylinder 17 is arranged in a concentric circle with the heater. The crucible is filled with It is the molten liquid of the crystallization raw material melted by the heater 12. Further, a lifting shaft 14 composed of a lifting rod or a wire is hung on the central shaft of the crucible. The front end of the lifting shaft 上 is interposed to support the seed crystal 15 mounted on the support Ua. These 7L pieces are housed in a pressure-controlled, water-cooled tank chamber 19. β Next, a method for pulling up the single crystal 丄 6 using the single crystal growing device described above will be described. First ’the inside of the chamber i 9 is decompressed, and then an inert gas is introduced.

Page 13 -44 6 7 6 4 5 'Explanation of the invention (Π) body' causes a reduced-pressure inert gas environment to be formed in the tank chamber 19, and thereafter, the heating burial 12 is energized to melt the raw materials for crystallization. Next, the pull shaft 14 is rotated at a certain speed in the opposite direction from the support shaft 18 at the same axis, and the seed crystal 15 mounted on the support 14a is lowered to bring it into contact with the molten liquid. 3 After the crystal 15 fully immersed in the melt 13, a single crystal 16 grew from the lower end of the seed crystal 15. In general, the diameter of the single crystal 16 is directly or indirectly identified by an optical or gravimetric sensor (not shown), and the development of the single crystal 16 is based on a preset and rotated single crystal diameter. The approximate value of the pulling speed of single crystal is implemented. Next, the outline of the single crystal growing method (1) related to the embodiment of the present invention will be described below. 1. Use the CCD camera to make the crystal diameter during crystal growth

2. Calculate the result from the measured value. 3. By using the speed of the learning work, the crystal deformation rate of D is within the range of%). Able to learn the control system, adjust the pull-up to the target crystal deformation rate (1, 5 to 2 〇

The result of this adjustment is to calculate “C.” in the above-mentioned RKK 2-image range. (Λο Set 8 real) The target pulling speed V during the incubation is set to B 稃 set by Kx α; ~ Iwasa 'Yuesei Early Crystallization 1 Use Figure 5

4 4ί β Τ δ 4 > V. Description of the invention (12) A method for cultivating a single crystal related to the application type, by pulling the crystal deformation rate to an appropriate value (1.5 to 2.0%) Increasing the speed straight, setting the 23 coefficient α ("8) 'can be the desired value of the laminated defect ring. Therefore, by reducing the above-mentioned accumulated defect lies in the non-defective area outside the laminated defect ring', it can be effectively achieved. The purpose of the single crystal is described below. The outline of the single junction I ^ sound & related to this embodiment is described in the following way. The method for cultivating the single crystal (2) is based on the above embodiment. Implemented the related single crystal growing method (1). 1. Measure the crystal diameter during crystal growing with a CC D camera. 2. Calculate the crystal deformation rate from the measured value. 3. Borrow = use learning Function of the learning control system, adjust the pulling speed, so that the stated crystal deformation rate is within the range of the target crystal deformation rate (12. 0%). · 4 · From this adjustment result, calculate the 2.0% Pull speed within the range ^. Do as early as 5 'with V = V0P X call (〇 , 3 $ LING), to obtain the target pull-up speed V during actual incubation, and set the target pull-up speed using at least two level systems " numerical sums and turns \ ', 6. The set 'and \' use the single crystal incubation shown in Fig. 5 to produce a single crystal 16. 7. Measure the diameter of the inner long defect ring on each of the single crystals 16 that were bred 1)

Page 15 4467 64 V. Description of the invention (13) 8. Calculate the diameter change rate (Di-D2) / β \-β 0 of the inner long defect ring from the measurement results. 9. Based on this calculation result, find the coefficient C used to set the diameter of the inner long defect ring to the desired value. 10. According to the obtained coefficient C, set the target pull-up speed V at the time of actual breeding to V = V0P XC. 11. According to the target pulling speed V set in 10 above, a single crystal 16 is grown using the single crystal device shown in Fig. 5. According to the method (2) for cultivating single crystals related to the above-mentioned embodiment, the aforementioned diameter change rate 'from all single crystals bred from the coefficients A and point 2 of at least two levels can be used throughout the single crystals. The total length is set to a desired value for the diameter of the inner-long defect ring. Next, a method (3) for growing a single crystal according to this embodiment will be described. However, 'this single crystal breeding method (3) is based on the early aa breeding method (1) or (2) related to the above implementation type', so for the single crystal breeding method (1) ) For the same part, its description is omitted. That is, in the single crystal growing method (3) related to the embodiment, the above 6 steps of the single crystal growing method (1) related to the embodiment , Or the actual pulling speed 拉, π, ν ± 0.4ν < in the above u step of (2), within the range starting from the crystallization incubation, and using the single knot V shown in FIG. 0: Single crystal 16. Take the clothes for the month m 446764 V. Description of the invention (14) According to the single crystal breeding method (3) related to the above implementation type, by controlling the range of the actual pulling speed Vr during breeding to an appropriate range v soil Within 0.4V, if the average pulling speed vac is controlled within an appropriate range v soil 0 · 0 2V, the variation range of the diameter of the laminated defect ring can be reduced without reducing the production efficiency of the single crystal 6. The single crystal (丨) related to the implementation form of the present invention is a single crystal produced by using the single crystal breeding method (1) to (3) according to the above implementation form, wherein Long defects are low density of Oii xi05 / cm3, and internal long defects are evenly distributed over the entire length of the single crystal. According to the single crystal (1) related to the above-mentioned embodiment type, because the internal length defects are low density, and the internal length defects are evenly distributed over the entire length of the single crystal, it can be obtained as a better part of semiconductor material Larger single crystals. You Tiani, the single crystal wafer (1) related to the implementation form of the present invention is to use the single crystal growth method (1) to (3) related to the above implementation form to slice the single crystal And a mirror-polished single-junction wafer is used, which uses a laser surface inspection machine to produce particles with a size of more than 0.3 μm when the wafer is 6 inches at 25 or less, and at 8 inches Wafers are less than M, and less than 1,000 at 12-inch wafers. According to the single-crystal wafer (1) related to the above-mentioned embodiment, a high-quality semiconductor with very few particle counts and excellent characteristics can be produced. The single-crystal wafer is related to the embodiment of the present invention. The circle (2) is a kind of single crystal bred from any of the methods for cultivating single crystals using the above-mentioned embodiment.

446764

446764

V. Explanation of the invention (16) The setting of the pull-up speed V0P of this single crystal is measured by a CCD camera during the crystallization incubation, and the crystal shape rate calculated from the measured value and the preset target deformation rate are measured. 8% 者。 (Here is 丨. 8%) For comparison, a learning control system with a learning function changes the pulling speed so that the crystal deformation rate becomes 1.8%. Second, multiplying the aforementioned pulling speed VQP by a certain coefficient α at any position X of the crystal position, and cultivate three crystals of ν (χ) = Kχ). Using 0.8, 0.6, and 0.4 as the coefficients α ^ In the crystal growth direction, two sample wafers were taken every 200 mm. One wafer was used to evaluate crystal defects, and the other wafer was used to measure build-up defects. The diameter of the ring. A wet oxygen environment corresponding to the oxygen concentration of the crystal is used for heat treatment, and then selective etching is performed with Wr ght solution, and the laminated defect is observed and the outer diameter of the laminated defect ring is measured, and the outer diameter is regarded as the aforementioned laminated defect. The diameter of the ring. For the other piece, no selective heat treatment was performed, but Secc0 liquid was used for selective etching, and the occurrence area of the inner-length defects existing on the inner side of the laminated defect ring was measured. The diameter of the long defect ring. Table 1 below shows the measurement results. [Table 1] Example 1 (0.8, Cream Example 2 (0.6)) Example 3 (0.4, (mm) (mm) (mm) 178 97 0 166 89 0 164 82 0 165 80 0 Product * Position (mm) layer 0 missing 200 depression 400 ring 600

446764 V. Description of the invention (17) Straight 800 160 88 〇 diameter 1_ 162 87 η average diameter Um) 166 87 ----- V π diameter unevenness (mffl) 18 17 -— \ L η within * position (mm ) (mm) (mm) ---- Ut (mm) length 0 165 87 0 missing 200 158 77 〇 depression 400 150 71 0 ring 600 155 73 〇 straight 800 151 75 〇 diameter 1000 15 4 75 π average diameter ΓιηπΟ 156 76 υ 〇 Uneven diameter Cmm) 15 16-0 Position: The position of the sample from the top of the crystal can be seen from the results shown in Table 1. In Examples i to 3, from the top of the crystal to the bottom, the defects are laminated. The ring diameter and the inner-length defect ring diameter are controlled to be approximately constant. In addition, since the unevenness is about 18 · and 16 mm in the examples and 2 reams, the unevenness can be suppressed. Further, in Example 3, the diameter of the layer defect ring and the diameter of the inner long defect ring were both zero. As for the comparative examples 1 and 2, the same as the conventional one is based on the limit pull speed determined by the operation intuition, and the evaluation results of the diameter of the long defect ring within 0-8 hours are disclosed below. However, Comparative Example 1 uses the single unit used in Examples 丨 to 3, while Comparative Example 2 uses the angles that are earlier than those in Examples 丨 to 3.

Page 20 446764 V. Description of the invention (18) '' --Incubation device, using single crystal incubation device with different structure in the hot zone. [Table 2] Comparative example 1 (0. Inner * position (mm) length 0 132 missing 200 168 depression 400 167 ring 600 173 straight 800 160 diameter 1000 155

_ Comparative Example 2 f η (mm) Average diameter (mm) 159 Diameter and unevenness (mm) 41 digits 118 137 145 130 112 106

—_ ^ w (^ w'J Ub ^ ^ From the results shown in Table 2, it can be seen that the method related to the comparative example does not have an intrinsic limit pull-up speed. In some cases, even if it is multiplied by a certain coefficient, it is not possible to obtain a certain region of occurrence of depression. Moreover, regardless of Comparative Example 1 or Comparative Example 2, Yin =, the unevenness of the diameters of the related inner-long defect rings are equivalent Yan Yue Fang Yi again, the coefficients obtained in Examples 1 to 3 are 〇8, 〇6, and 板 three plate crystals, respectively, the whole length is sliced along the pull direction, and the single crystal wafer is made by the product ^, etc. The wafer was sc — 丨: = the surface inspection machine inspected its surface. The number of inspection pieces was 4: 2. The following table 3 is used to reveal the average “count value of particles with a size of 0,13 in m or more”.

Page 21 446764 Fifth invention description (19) Table 3 — __ coefficient to implement your Π 0. 8 k embodiment 2 0.6 implementation office 13 0.4 count value / wafer 22 to 49 ′ ——— U 〇 __ ^ From Table 3 As a result, it can be known that, in any case, the count value is extremely small, and the distribution of the aforementioned particles is in a single crystal; the particles are equal to the sergeant system. The semiconductor device produced due to the use of Λ 'and the examples has very good characteristics and high quality ^ σσ. In the single crystal obtained in Example 3 (with a coefficient of 4 or less), the particles are described. The count value is 8 pieces / wafer or less, which is substantially zero... 0. Next, the fourth embodiment when the single crystal method (2) related to the above embodiment is used will be described. The average diameter of the inner-long defect ring obtained from two crystals having a coefficient of 0.8 (Example 1) and a coefficient of 0.6 (Example 2) in the crystals obtained by throwing them in Examples 1 to 3. Diie (refer to Table 1), the diameter change rate (ΑΜε / Δ △) was calculated from the coefficient 泠 and the average diameter Dde. Using this diameter change rate, try to grow a crystal with a diameter of 100 mm in the inner long defect ring. The following calculations were performed using the average diameters of 156 mm and 76 mm when the coefficients shown in Table 1 were 0.8 and 0.6. The rate of change of the diameter of the defect occurrence area = (156-76) / (0.8-0.6) = 400 Therefore, the crystallization requirement for the inner long defect ring with a diameter of 100 mm

Page 22 4-46-6 4 V. Explanation of the invention (20) ~ 〇〇-〇. 6) = 100 The formula can be obtained by taking the coefficient cig〇, which can be obtained from 76 + 400 X (C to obtain CufO 66 The value incubation of Ιίΐ4Λ 'is performed using the same evaluation method as the pull-up speed set at v = VxG.66. From the results in Table 4, it can be obtained that the diameter of the inner length ^ ring is approximately the target 10 (near ^^). Value. Table 4]

Diameter Unevenness (min ') ---___ I Dagger position: the position of the sample from the top of the crystal [Examples 5 to 8] Next, the example when the single crystal (3) related to the above embodiment is used will be described. 5 to 8. The conditions are described below. [Common conditions for Examples 5 to 8] 'The amount of raw materials for crystallization: 100 kg Gas environment in the chamber 19: Ar gas environment

Page 23 446764 V. Description of the invention (21)

Flow rate of Ar '100 liters / minute Pressure in the furnace: 2660Pa (approximately 20 Torr) Diameter of the crucible 11: 22 inches drawn single crystal 16 Shape diameter: 8 inches Length: 1 OGOmni Average crystal pulling speed: 0 8mm / minute The pulling speed Vqp set in the above Example 1 is multiplied by a coefficient 0.8 which is the same at any position of the crystal position X, and the crystal is grown under the condition of V (x) = (x) X 0.8. . In order to keep the crystal diameter at the set diameter value (8 inches), it corresponds to the difference from the measured crystal value. After performing a 5 second cycle at the pull speed, the calculated pull speed control value is returned. And the formula V (x) = V0P (x) X0.8 is applied to the pull-up speed Vr (x) 'at the time of incubation, and a certain control range is set to implement crystallization incubation. That is, the conditions of Examples 5 to 8) were performed with respect to the speed V 'given 0.2 times, 0.4 times, 0.6 times, and 0.8 times of the upper and lower conditions V, and the results were the same as in Examples 1 to 3. The field ο is the same as the diameter of the inner long defect ring. The measurement results are shown in Table 5 below.

[Table 5] Example of the average speed of the change in the diameter of the fan garden Example 5 V ± 0. 2V 15mm V ± 0. 004V Example 6 V soil 0.4 V 1 5 mm V ± 0. 020V Example 7 V ± 0. 6V 3 2mm V ± 0. 026V

Page 24 446764 V. Description of the invention (22)

Example 8 V soil 0.8 V 45 mm V ± 0.03 V From the results in Table 5, it can be seen that 'the pull speed Vr during crystal growth is controlled within the range of V ± 0.2 V or V ± 0.4 V'. The variation in the diameter of the defect is about 15 mm in the growth direction of the crystal, and it is 32 mm in the range of V 'and 45 mm in the range of V ± 0.8 V, which becomes a large value. Also, when investigating the average pulling speed Vac within 60 minutes from the start of crystallization, it can be found that, in the order of Examples 5 to 8, the values are v ± qq〇4V, V ± 0.020V, V ± 0.26V and V ± 0.033V 〇 In order to enlarge the non-defective area and make effective use, it is better to set the diameter of the inner-length defect generation area to 140011111 or less on an 8-inch wafer, but at this time, the crystal pulling The average lifting speed must be set to Vqp xCi4G (Ci4Q = about 0.75 (refer to the following formula 3). If the diameter of the inner long defect area has a large change, the relative pulling speed must be set. For example, when it corresponds to a variation of 32mra (Example 7), if it is not set to V () p > < Cm (Cifl8 = 0.68C, refer to the following formula 4)), the internal length defect cannot be determined. The maximum diameter of the ring is formed below 140mni. In the case of an 8-inch wafer ', when the diameter of the inner long defect ring is set to 140 mm, the coefficient Ci4o can be calculated according to the fourth embodiment. ^ 6 + 400 X (CI4fl-0.6) -140 When the diameter of the inner long defect ring is set to 108 mm on an 8-inch wafer, the coefficient CU8 can be calculated according to the fourth embodiment. ^ 6 + 400 x (C108-〇. 6) = 108 Because the production efficiency will decrease when the coefficient C is small, it is necessary to avoid setting the coefficient C to an excessively low value below the required value. For this reason, try to suppress growth

Page 25 (23) The diameter variation of the inner long defect ring in the direction of 4 46 7 6 4 is better. Therefore, if the pulling speed Vr of each f-system cycle is controlled within the range of v ± 0,4, the crystallization month The change of the average pulling speed Vac within 60 minutes from the start of $ will be less than v ± .0V, which will make the diameter change of the inner long defect ring smaller. The coefficient C at this time is about 0.72. [Brief description of the drawing] Fig. 1 is a model circle showing the general relationship between the pull-up speed and the location of crystal defect generation during the growth of single crystals. Fig. 2 is a schematic view showing a state of a crystal plane perpendicularly intersecting with a crystal pulling direction. Fig. 3 is a schematic diagram showing the relationship between the amorphous deformation rate and the diameter of the laminated defect ring. Fig. 4 is a graph showing the relationship between the crystal deformation rate of the samples shown in Fig. 3 and the pulling speed when the samples are grown. ^ Figure 5 is a model wearing diagram of the single crystal incubation device used in the CZ method. Fig. 6 is a schematic diagram of the corresponding pulling speed Vqp of each crystal length of a single crystal with a crystal deformation rate in the range of 15 to 1.8% over the entire length of the single crystal.

Claims (1)

1. A single crystal breeding method, which involves immersing seed crystals in the molten liquid in the crucible, and then cultivating single crystals by pulling the seed crystals, which is characterized by the following steps: precalculation and crystal pulling The step of the pulling speed VQP within the range of 1.5 to 2.0% of the crystal deformation rate represented by "(maximum diameter-minimum diameter) / minimum diameter" in the plane that intersects the lifting direction perpendicularly; The target pulling speed V is set to V7VQP X α (a S 0 · 8), and a step of cultivating single crystals. 2. If the single crystal breeding method of item 1 of the patent application scope includes the following steps: Calculate in advance the plane that intersects the crystal pulling direction perpendicularly with \ '.. "(maximum diameter-minimum diameter) / minimum The step of "diameter" refers to a pulling speed V0P in which the crystal deformation rate is in the range of 1.5 to 2.0%; the target pulling speed V Shaw during actual breeding V Shao V = V0P X / 3 (p. 3 S / 5S1.0). Steps of cultivating single crystals based on the aforementioned target pulling speed of at least two level coefficients Lu I and Shi 2. Measure the diameter of the long defect ring in each single crystal. D !, 1) Step 2; From this measurement, the step of calculating the diameter change rate of the inner long defect ring (Duang D2) / (Xing!-/ 9 2) Step; Based on this calculation result, find The coefficient used to set the diameter of the inner long defect ring to the desired value (the step of 2.) 3. If the single crystal incubation method of item 1 or item 2 of the patent application park is applied, the pulling speed during actual incubation Vr is controlled in the range of Vr = V ± 0.4V A: \ 310198.ptc Page 1 2000.12.28.028 446764 _Case No. 871214S4 "Monthly Zheng _ VI, application _ within the scope of patents" and the average pull-up within a certain period of time from the start of the single crystal pull-up The speed Vac is controlled within the range of Vac = V ± 0.02V. 4. If the single crystal of item 1 or item 2 of Fang Hai is cultivated, the coefficient α is 0.6 or less. 5. According to item 3 of the scope of patent application A single crystal breeding method, wherein the coefficient α is 0.6 or less. 6 · A single crystal wafer is a single crystal bred by the single crystal breeding method of the patent application scope item 1 or item 2 along the pull direction The whole length is sliced and 'mirror-polished to make a single crystal wafer'. It is implemented using a laser surface inspection machine: 0! 3 " The count value of particles larger than m in 6 inch crystals It is 25 or less at round time, 50 or less at 8-inch wafers, and 1000 or less at 12-inch wafers. 1 'A single crystal β, which will be used and applied for the third patent scope The single crystal bred by the single crystal growing method is sliced along the entire length of the pulling direction, and then applied. A single crystal wafer is made by mirror grinding, etc. The value of "13." which is the size of a particle is not used, and it is 25 or less when the wafer is called 6 inches, and it is 8 inches. The wafer time is 50 or less, and in the case of a 2-inch leaf wafer, it is 100 卞. 8_ A single crystal wafer is a single crystal produced by the single crystal breeding method in the fourth patent application scope along the pull direction. A single crystal wafer is made by slicing the whole length and then applying mirror polishing, etc. The count value of particles with a size of Q. 13 or more performed by a laser inspection machine is substantially zero. ^ 9 * A single Crystalline wafers will adopt the single junction of the scope of patent application No. 5 娜娜 · ptc 2000.12.28, 029, Γ.-. .......:: Α .. ... ·.. J ·. ___________ / /, :: ..... 446764 _ Case No. 87121484 / Factory Year / Month / Day Amendment_ VI. Patent Application Scope—Single crystals bred by the crystal growing method are sliced along the entire length of the pulling direction, and then a single crystal wafer is made by mirror polishing, etc. The count value of particles with a size of 0.13 / zni or more implemented by a laser's surface inspection machine is substantially zero. A: \ 310198.ptc Page 3 2000, 12.28.030