JP4962406B2 - Method for growing silicon single crystal - Google Patents

Description

  The present invention relates to a method for growing a semiconductor silicon single crystal, and more specifically to a method for growing a carbon-doped silicon single crystal in which the resistivity is suppressed from deviating from a desired range even when heat treatment is performed.

Since semiconductor devices form elements on the surface layer of a silicon single crystal wafer, it is important that there are no defects on the wafer surface layer.
As a method for manufacturing such a wafer, there is a method of cutting a wafer from a defect-free crystal pulled so as not to form crystal defects in the crystal growth stage. This is characterized in that it is difficult to control parameters during crystal growth and the crystal cost is increased.

  On the other hand, there are wafers where crystals are grown under conditions that cause crystal defects during crystal growth and then annealed to eliminate crystal defects near the surface layer, and wafers with deposited epitaxial layers without crystal defects. . These crystals are generally inexpensive, as shown in Patent Document 1, since crystals with a high growth rate that do not include the I region are used. However, since there is an additional process, the total cost is higher than that of defect-free crystals.

In the method of detoxifying crystal defects in the vicinity of the surface layer in the subsequent process using a crystal having these crystal defects, added value is required because the total cost is higher than the wafer cut out from the defect-free crystal. .
As an added value, BMD (Bulk Micro Defect) is formed inside the wafer to add gettering capability in many cases. In the case of an annealed wafer, it is possible to form a BMD by devising the annealing process conditions.

However, in general, since epitaxial layers are formed at high temperatures in epitaxial wafers, BMD nuclei formed during crystal growth disappear during heat treatment during epitaxial layer formation, and thus BMDs are difficult to form. .
In order to improve these, carbon-doped epitaxial wafers such as those shown in Patent Document 2 and Patent Document 3 have been proposed for a long time and have been put into practical use up to now.

  On the other hand, by doping with carbon, thermal donors generated at around 430 ° C. are suppressed (see Non-Patent Document 1), new donors generated at around 700 ° C. are increased (see Non-Patent Document 2), etc. Has been reported. In addition, Patent Documents 4 and 5 propose to dope carbon to suppress a thermal donor in a high resistivity crystal or the like as a document using an effect of suppressing a thermal donor.

JP 2000-219598 A JP 59-82717 A JP 59-94809 A International Publication No. 04/008521 JP-A-2005-123351 A. R. Bean and R.C. C. Newman, J .; Phys. Chem. Solids 33, 255 (1972) A. Kanamori and M.M. Kanamori, J. et al. Appl. Phys. 50, 8095 (1979)

  Until now, since the device process was generally a high-temperature treatment, the influence of carbon on the donor was not considered as a problem. In particular, the effect of suppressing thermal donors by carbon is well known, and since it is an effect of suppressing thermal donors rather than being generated, it was not particularly regarded as a problem.

  However, in recent years, it has become clear from examinations by the present inventors that donors generated by doping carbon become a problem as the device temperature decreases. In other words, when the donor is generated, the resistance value changes, which may affect the device manufacturing.

  The present invention has been made in view of the above problems, and silicon that can be made into a silicon single crystal wafer having a desired resistivity even if a donor is generated during the heat treatment in a device manufacturing process or the like by doped carbon. It is an object of the present invention to provide a method for growing a single crystal and a method for producing a silicon epitaxial wafer produced from the silicon single crystal.

In order to solve the above-described problems, the present invention provides a method for growing a silicon single crystal, which is accompanied by carbon doping when growing a silicon single crystal by doping carbon and a resistance adjusting dopant by the Czochralski method. previously calculates a shift amount of resistivity that occurs, it that provides the method for growing a silicon single crystal, characterized in that adjusting the doping amount of said resistance adjusting dopant in accordance with the shift amount.

  As described above, when a heat treatment is performed on a wafer cut from a carbon-doped silicon single crystal, the resistivity may change before and after the heat treatment. However, when a silicon single crystal doped with carbon and a resistance adjusting dopant is grown as in the present invention, the amount of resistivity shift generated with carbon doping is calculated in advance, and the resistance adjusting dopant doping amount is calculated. Therefore, even if a donor is generated in the wafer by heat treatment, the resistance is deviated from a desired value because the dopant for adjusting the resistance is adjusted by the amount of the donor and is doped. This can be suppressed.

Further, the method of calculating, by doping carbon and resistance adjusting dopant by Czochralski method to grow a preliminary silicon single crystal, after slicing the preliminary silicon single crystal and processing into a preliminary silicon single crystal wafer, After measuring the resistivity and carbon concentration of the preliminary wafer, and then performing a heat treatment simulating the heat treatment in the device process on the preliminary wafer, measuring the resistivity of the heat treated preliminary wafer, the resistivity before and after the heat treatment It is preferable that the amount of donor generation is obtained from the amount of change in the amount of the resistivity, and the resistivity shift amount relative to the amount of carbon doping in the silicon single crystal wafer is calculated from the relationship between the amount of donor generation and the carbon concentration before the heat treatment. Yes.

  In this manner, a preliminary silicon single crystal wafer is prepared in advance, and a heat treatment similar to the heat treatment performed in the device manufacturing process is performed to evaluate how much the resistivity of the preliminary silicon single crystal wafer changes due to the heat treatment. Then, by correlating the donor generation amount obtained from the evaluated change in resistivity and the doped carbon amount, the resistivity shift amount with respect to the carbon doping amount can be calculated. As a result, the amount of resistivity shift can be calculated with high accuracy, so that a silicon single crystal that can be used as a wafer having a desired resistivity can be grown more easily.

Further, the method of calculating, by doping carbon and resistance adjusting dopant by Czochralski method to grow a preliminary silicon single crystal, sliced the preliminary silicon single crystal and processed into a preliminary silicon single crystal wafer, After measuring the resistivity and carbon concentration of the preliminary wafer, and then performing heat treatment simulating the heat treatment in the device process on the preliminary wafer, measuring the resistivity and carbon concentration of the preliminary wafer before and after the heat treatment The amount of donor generated is determined from the amount of change in carbon concentration and the amount of change in resistivity of the preliminary wafer, and from the relationship between the amount of donor generated and the amount of change in carbon concentration, the resistivity shift with respect to the amount of carbon dope in the silicon single crystal wafer It has preferably be made to calculate the amount.

  Thus, by preparing a preliminary silicon single crystal wafer in advance and performing a heat treatment similar to the heat treatment performed in the device manufacturing process, how much the resistivity and carbon concentration of the preliminary silicon single crystal wafer change due to the heat treatment. evaluate. Then, by correlating the amount of donor generation obtained from the amount of change in resistivity evaluated and the amount of change in carbon concentration, the amount of resistivity shift relative to the amount of change in carbon concentration can be calculated. As a result, the amount of resistivity shift can be calculated with higher accuracy, so that a silicon single crystal that can be used as a wafer having a desired resistivity can be easily grown.

In the present invention, after the silicon single crystal grown by the silicon single crystal growth method according to the present invention is sliced and processed into a silicon single crystal wafer, an epitaxial layer is formed on the main surface of the wafer. that provides a method for manufacturing a silicon epitaxial wafer, comprising.
As described above, since the silicon single crystal grown by the growth method of the present invention is doped with the resistance adjusting dopant adjusted by the amount of the generated donor even if the donor is generated in the wafer by the heat treatment, the resistance is increased. The rate is suppressed from deviating from a desired value. For this reason, by forming an epitaxial layer on the main surface of a silicon single crystal wafer processed from such a silicon single crystal, the silicon epitaxial in which the resistivity is prevented from deviating from a desired value even if heat treatment is performed. A wafer can be obtained. Further, since carbon is doped, BMD can be formed relatively easily by performing oxygen precipitation heat treatment, so that the gettering ability can be increased.

According to the present invention, Ki out to provide a silicon single crystal, characterized in that it is grown by growing method of the present invention, and silicon, characterized in that cut out from such a silicon single crystal Ru it is possible to provide a single crystal wafer.
Further according to the present invention, Ru can provide an epitaxial wafer, characterized in that in which the epitaxial layer is formed on the main surface of the silicon single crystal wafer of the present invention.

  As described above, according to the method for growing a silicon single crystal of the present invention, the amount of change in resistivity is predicted from the carbon concentration or the amount of change in carbon concentration, and the resistance of the predicted amount is corrected to compensate for the silicon single crystal grown. A silicon single crystal wafer cut out from such a silicon single crystal can also have a desired resistivity after heat treatment in the device process, and is suitable for manufacturing a device. Wafer. Further, an epitaxial wafer in which an epitaxial layer is formed on the surface of such a silicon single crystal is also suitable for manufacturing a device and becomes a wafer with few crystal defects.

  As described above, the method for growing a carbon-doped silicon single crystal of the present invention is to grow by calculating the resistivity shift amount in advance and adjusting the doping amount of the resistance adjusting dopant according to the shift amount. Therefore, even if a donor is generated during the heat treatment in the device manufacturing process or the like due to the doped carbon, a silicon single crystal that can be processed into a silicon single crystal wafer having a desired resistivity can be grown.

Hereinafter, the present invention will be described more specifically.
As described above, even if a donor is generated during heat treatment in a device manufacturing process or the like due to carbon doped in the silicon single crystal wafer, the silicon single crystal can be grown to have a desired resistivity. The development of the method was awaited.

  Therefore, the present inventors have examined whether the above problem can be solved by adjusting a dopant for resistance adjustment in advance when growing a single crystal.

  As a result, the present inventors calculated the amount of donors generated in advance, calculated the resistivity shift amount based on the calculated value, and adjusted the doping amount of the resistance adjusting dopant for the shift, for example, after heat treatment As a result, it has been found that a silicon single crystal capable of obtaining a silicon single crystal wafer having a desired resistivity can be grown, and the present invention has been completed.

The details of the examination results are shown below.
(Experiment 1)
As shown in FIG. 1, a quartz crystal crucible 5 having a diameter of 22 inches (550 mm) and a graphite crucible 6 that supports the single crystal growth apparatus 11 including the main chamber 1 and the pulling chamber 2 are equipped with a diameter of 8 inches. A (200 mm) silicon single crystal 3 was grown.

In general, in the CZ method, a quartz crucible 5 held by a melt 4 and a graphite crucible 6 supporting the quartz crucible, a heater 7 arranged so as to surround the crucible, a heat insulating member 8 arranged around the heater, a main chamber 1 And a gas inlet 10 for introducing gas into the pulling chamber 2 and a gas outlet 9 for discharging gas.
After immersing the seed crystal in the quartz crucible 5, the rod-shaped single crystal 3 is pulled up from the melt 4. The crucible can be moved up and down in the direction of the crystal growth axis, and the crucible is raised so as to compensate for the lowering of the liquid level of the raw material melt that has decreased during crystal growth.

At this time, carbon and P (phosphorus) were doped so that the carbon concentration in the silicon single crystal was 4 to 10 × 10 ¹⁶ atoms / cc and the resistivity was 15 to 30 Ωcm.
Thereafter, wafer-like samples were cut out from several locations of the silicon single crystal, and carbon concentration measurement by FT-IR (Fourier transform infrared spectrophotometer) and resistivity measurement by a four-probe measuring instrument were performed. Prior to this resistivity measurement, a donor killer treatment was performed at 650 ° C.

  As a result, a silicon single crystal wafer having a carbon concentration and resistivity as shown in FIG. 2 with respect to the solidification rate was obtained, which was in accordance with the initial aim.

The purpose of doping with carbon is to obtain a large amount of BMD. In order to confirm this, BMD was measured using a wafer-like sample whose resistivity was measured. As the heat treatment at this time, heat treatment conditions (1150 ° C./1 h + 700 ° C./5 h + 1000 ° C./8 h) including the device heat treatment and imitating the heat treatment that this wafer will receive through the following various processes are simplified. Was used.
As a result, it was found that BMD was sufficiently generated.

Next, the resistivity was measured again on the heat-treated wafer.
As a result, it was found that there was a deviation from the initially measured value. The result is shown in FIG.
At the higher solidification rate, it was initially 15 Ωcm or more and was within the standard, but it was found that the standard was interrupted after the heat treatment. This is out of the resistivity of the operating range of the device, and may be a cause of defects when manufacturing the device.

The heat treatment performed this time includes heat treatment at 700 ° C., and it is considered that a donor due to carbon was generated. In this heat treatment, since the heat treatment is performed at 700 ° C. and then at 1000 ° C., the resistivity shift is not so large. However, in consideration of the recent reduction in device process temperature, a certain amount of resistivity may be required. A shift is expected.
Based on the above experience, we first came up with the idea that it is important to predict the amount of resistivity shift.

(Experiment 2)
As described above, since it is considered that the resistivity is changed by the carbon-derived donor, the relationship between the carbon concentration and the amount of generated donors was examined. Therefore, phosphorus-doped silicon single crystals with different carbon concentrations were grown using the same apparatus and method as in Experiment 1.

  A wafer-like sample was cut out from these silicon single crystals, subjected to donor killer treatment, and then the resistivity was measured by a four-point probe method. At the same time, the carbon concentration was also measured using FT-IR.

  After that, these sample wafers were heat-treated (1150 ° C / 1h + 700 ° C / 5h + 1000 ° C / 8h were used again), and the resistivity and carbon concentration were measured again by the four-probe method and FT-IR. .

The amount of donor generated by the heat treatment was determined from the difference in resistivity before and after the heat treatment. When this was plotted against the carbon concentration before heat treatment, FIG. 4 was obtained.
In FIG. 4, when the amount of generated donor is [C] d and the initial carbon concentration is [C] c ₀ , [C] d = 5.4 × 10 ⁻²¹ ([C] c ₀ ) ² −1.5 × 10 ⁻⁴ ([C] c ₀ ) + 3.5 × 10 ¹²
The relationship is obtained. From this relationship, for the heat treatment condition: (1150 ° C./1 h + 700 ° C./5 h + 1000 ° C./8 h), the donor generation amount after the heat treatment can be calculated from the initial carbon doping amount.

Further, FIG. 5 is obtained by plotting the generated donor amount obtained from the difference in resistivity before and after the heat treatment against the amount of change in carbon concentration measured by FT-IR before and after the heat treatment.
From the relationship of FIG. 5, assuming that the generated donor amount is [C] d and the carbon concentration change amount is [C] cc,
[C] d = 6.5 × 10 ⁻²¹ ([C] cc) ² −3.6 × 10 ⁻⁴ [C] cc + 3.4 × 10 ¹²
The relationship is obtained. From this relationship, for the heat treatment condition: (1150 ° C./1 h + 700 ° C./5 h + 1000 ° C./8 h), the amount of donor generated after the heat treatment can be calculated from the amount of carbon concentration change before and after the heat treatment.

  As described above, if the relationship between the carbon concentration or the amount of change in carbon concentration before and after the heat treatment and the amount of donor generated is determined in advance for the heat treatment expected in the device process, the amount of donor generated after the device process can be predicted. It was found that the resistivity shift amount can be calculated.

(Experiment 3)
Then, using the same apparatus and method as in Experiments 1 and 2, a silicon single crystal having a carbon concentration of 4 to 10 × 10 ¹⁶ atoms / cc and a silicon single crystal wafer having a resistivity of 15 to 30 Ωcm was pulled. However, this time, the resistivity after the heat treatment was controlled to be 15 to 30 Ωcm.

  First, the carbon concentration at each position of the silicon single crystal was calculated from the amount of carbon to be doped, and the resistivity shift amount after the heat treatment in the device process was calculated from the calculated carbon concentration. FIG. 6 shows the result of adjusting the phosphorus concentration from the calculated resistivity shift amount and calculating the resistivity after heat treatment obtained as a result.

Based on this calculation, a silicon single crystal was actually grown. A wafer-like sample was cut out from the silicon single crystal, and the resistivity was measured by a four-probe method after the donor killer treatment. The results are shown in FIG. Naturally, since the resistivity shift amount is expected, it was found that the value on the low solidification rate side exceeded 30 Ωcm.
These samples were subjected to heat treatment under the heat treatment conditions: (1150 ° C./1 h + 700 ° C./5 h + 1000 ° C./8 h), and then the resistivity was measured again. The results are shown in FIG. As shown in FIG. 7, it was found that the resistivity was in the target 15-30 Ωcm.

  In the above experiment, the case of the N type was shown, but it was confirmed that a donor was similarly generated in the P type and the resistivity was shifted. However, in the case of the P type, the resistivity is shifted to a higher one, so that it can be calculated in the same manner by taking this into consideration.

  Hereinafter, the method for growing a silicon single crystal of the present invention will be described in detail. Note that, here, the case where the resistivity shift amount is calculated from the carbon concentration before the simulated heat treatment simulating the heat treatment in the device process, the carbon concentration change amount before and after the heat treatment, and the amount of donor generation will be described as an example. Of course, the present invention is not limited to this. It is within the scope of the present invention that a silicon single crystal is grown by calculating in advance the amount of resistivity shift caused by carbon doping and adjusting the doping amount of the resistance adjusting dopant according to the amount of shift. .

  First, a preliminary silicon single crystal for investigation is grown by the Czochralski method. At this time, the preliminary silicon single crystal is doped with carbon and a resistance adjusting dopant. A general method may be used for doping the carbon and the resistance adjusting dopant.

  Next, after the grown preliminary silicon single crystal is sliced by a cutting device such as an inner peripheral slicer or a wire saw, a preliminary silicon single crystal wafer is manufactured through processes such as chamfering, lapping, etching, and polishing.

Then, the resistivity and carbon concentration of the preliminary silicon single crystal wafer are measured.
The resistivity may be measured by a general method, but can be easily measured by the four-probe method.
In addition, the carbon concentration may be measured by using a general method, but it is desirable to evaluate the carbon concentration by FT-IR having advantages such as easy measurement.

Thereafter, heat treatment simulating heat treatment in the device process is performed.
The heat treatment simulating this device process differs depending on the device produced on the silicon single crystal wafer cut out from the produced silicon single crystal, and therefore heat treatment conditions may be appropriately selected for each production device.

Then, the resistivity and carbon concentration of the preliminary silicon single crystal wafer are measured even after the heat treatment.
The resistivity / carbon concentration is measured by the same measurement method as that measured before the heat treatment.

And the amount of donor generation | occurrence | production can be calculated | required from the variation | change_quantity of the resistivity before and behind heat processing, and a resistivity shift amount can be calculated from the relationship between this donor generation amount and carbon concentration. Further, the amount of donor generation can be obtained from the amount of change in resistivity before and after the heat treatment, and the resistivity shift amount can be calculated from the amount of donor generation and the amount of change in carbon concentration.
Thus, when the relationship between the carbon concentration and the amount of donor generation or the relationship between the carbon concentration change amount and the amount of donor generation is obtained, and the resistivity shift amount is calculated from the relationship, the resistivity shift amount can be accurately estimated. Then, by adjusting the doping amount of the resistance adjusting dopant based on the estimated shift amount, a silicon single crystal that can be made into a silicon single crystal wafer having a desired resistivity after the device process is grown. can do.

  Then, the doping amount of the resistance adjusting dopant is adjusted based on the resistivity shift amount obtained by the calculation method as described above, and the silicon single crystal is doped with carbon and the resistance adjusting dopant by the Czochralski method. Cultivate.

Here, the grown silicon single crystal can be processed into a silicon single crystal wafer.
As described above, since the silicon single crystal grown by the growth method of the present invention has a desired resistivity even when a donor is generated during the heat treatment in the device manufacturing process or the like due to the doped carbon, this is the case. A silicon single crystal wafer obtained by processing a simple silicon single crystal can also have a desired resistivity.

Furthermore, an epitaxial layer can be formed on the main surface of the produced silicon single crystal wafer.
General conditions can be used for forming the epitaxial layer. For example, a source gas such as SiHCl ₃ may be introduced into the chamber using H ₂ as a carrier gas, and epitaxial growth may be performed by CVD at about 1050 to 1250 ° C. on the silicon single crystal wafer placed on the susceptor.

  Since such a silicon epitaxial wafer is doped with carbon, BMD can be formed relatively easily by oxygen precipitation heat treatment. Further, since the resistivity is suppressed from deviating from a desired value even when heat treatment is performed, the resistivity is hardly deviated from the standard during device manufacturing, and a device can be manufactured with a high yield.

  As described above, according to the method for growing a silicon single crystal of the present invention, since the resistance adjusting dopant in an amount corresponding to the resistivity shift amount that is changed by the donor generated by the heat treatment is adjusted and doped, the device Even when heat treatment is performed in a process or the like, a silicon single crystal that can cut out a silicon single crystal wafer in which the resistivity is suppressed from deviating from a desired value can be grown. Moreover, since carbon is doped, BMD can be deposited in the wafer by device heat treatment. Therefore, a wafer with high gettering capability can be obtained.

EXAMPLES Hereinafter, although an Example and a comparative example are shown and this invention is demonstrated more concretely, this invention is not limited to these.
(Example)
A quartz crystal crucible having a diameter of 22 inches (550 mm) and a graphite crucible supporting the quartz crucible and a graphite crucible for supporting the quartz crucible as shown in FIG. 1 were grown to grow a preliminary silicon single crystal having a diameter of 8 inches (200 mm).
At this time, carbon and P (phosphorus) were doped so that the carbon concentration in the preliminary silicon single crystal was 4 to 10 × 10 ¹⁶ atoms / cc and the resistivity was 15 to 30 Ωcm.

Thereafter, wafer-like samples were cut out from several locations of the preliminary silicon single crystal, and carbon concentration measurement by FT-IR and resistivity measurement by a four-probe measuring instrument were performed. Prior to this resistivity measurement, a donor killer treatment was performed at 650 ° C.
After that, these sample wafers were heat-treated (1150 ° C / 1h + 700 ° C / 5h + 1000 ° C / 8h were used again), and the resistivity and carbon concentration were measured again by the four-probe method and FT-IR. .

The amount of donor generated by the heat treatment was determined from the difference in resistivity before and after the heat treatment. When this was plotted against the carbon concentration before heat treatment, FIG. 4 was obtained.
From the relationship of FIG. 4, when the amount of generated donor is [C] d and the initial carbon concentration is [C] c ₀ , [C] d = 5.4 × 10 ⁻²¹ ([C] c ₀ ) ² −1.5 × 10 ⁻⁴ ([C] c ₀ ) + 3.5 × 10 ¹²
The relationship was obtained.

Then, using the same apparatus and method as before, we decided to pull up a silicon single crystal with a carbon concentration of 4 to 10 × 10 ¹⁶ atoms / cc and a silicon single crystal wafer with a resistivity of 15 to 30 Ωcm. However, this time, the doping amount of phosphorus was controlled based on the relational expression obtained from FIG. 4 so that the resistivity after heat treatment was 15 to 30 Ωcm.

In other words, the carbon concentration at each position of the silicon single crystal is calculated from the amount of carbon to be doped, and the resistivity shift amount after the heat treatment in the device process is calculated from the calculated carbon concentration using the formula shown above. did. FIG. 6 shows the result of adjusting the phosphorus concentration from the calculated resistivity shift amount and calculating the resistivity after heat treatment obtained as a result.
Based on this calculation, a silicon single crystal was actually grown. A wafer-like sample was cut out from the silicon single crystal, and the resistivity was measured by the four-probe method after the donor killer is shown in FIG. Naturally, since the resistivity shift amount is expected, it was found that the value on the low solidification rate side exceeded 30 Ωcm.

  These samples were subjected to heat treatment under the heat treatment conditions: (1150 ° C./1 h + 700 ° C./5 h + 1000 ° C./8 h), and then the resistivity was measured again. The results are shown in FIG. As shown in FIG. 7, it was found that the resistivity was in the target 15-30 Ωcm.

(Comparative example)
Using a device similar to that of the example, a single crystal having a carbon concentration of 4 to 10 × 10 ¹⁶ atoms / cc and a silicon single crystal wafer having a resistivity of 15 to 30 Ωcm was pulled.
Thereafter, the sample silicon single crystal wafer was subjected to the same heat treatment as in the example, and the resistivity of the wafer after the heat treatment was measured.

As a result, it was found that there was a deviation from the initial target value. The result is shown in FIG.
At the higher solidification rate, it was initially 15 Ωcm or more and was within the standard, but it was found that the standard was interrupted after the heat treatment.

  The present invention is not limited to the above embodiment. The above-described embodiment is an exemplification, and the present invention has any configuration that has substantially the same configuration as the technical idea described in the claims of the present invention and that exhibits the same effects. Are included in the technical scope.

It is an example of the schematic of a silicon single crystal growth apparatus. 6 is a graph showing a relationship between a carbon concentration distribution and a resistivity distribution in a crystal axis direction obtained from the silicon single crystal wafer of Experiment 1. FIG. 6 is a graph showing the relationship of resistivity distribution in the crystal axis direction before and after heat treatment of the silicon single crystal wafer in Experiment 1. FIG. 6 is a graph showing the relationship between the carbon concentration of a silicon single crystal wafer in Experiment 2 and the amount of donors generated. It is the graph which showed the relationship between the carbon concentration change amount of experiment 2, and the amount of donor generation. It is the graph which showed the relationship between the estimated donor generation amount of the silicon single crystal wafer of Experiment 3, and the estimated resistivity after heat processing. It is the graph which showed the relationship between the initial stage resistivity of the silicon single crystal wafer of Experiment 3, and the resistivity after heat processing.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Main chamber, 2 ... Pulling chamber, 3 ... Single crystal, 4 ... Raw material melt, 5 ... Quartz crucible, 6 ... Graphite crucible, 7 ... Heating heater, 8 ... Heat insulation member, 9 ... Gas outlet, 10 ... Gas Inlet 11, single crystal growing device.

Claims (3)

A method for growing a silicon single crystal,
When a silicon single crystal is grown by doping carbon and a resistance adjusting dopant by the Czochralski method, a shift amount of resistivity generated with carbon doping is calculated in advance, and the doping amount of the resistance adjusting dopant is calculated. According to the method of adjusting according to the shift and calculating, the preliminary silicon single crystal is grown by doping carbon and a resistance adjusting dopant by the Czochralski method, and the preliminary silicon single crystal is sliced to prepare After processing into a silicon single crystal wafer, the resistivity and carbon concentration of the preliminary wafer are measured, and then the preliminary wafer is subjected to heat treatment simulating the heat treatment in the device process, and then the resistivity of the heat-treated preliminary wafer is determined. Measure, determine the amount of donor generated from the amount of change in resistivity before and after the heat treatment, the amount of donor generated and the carbon concentration before the heat treatment From the relationship, characteristics and to Cie method for growing a silicon single crystal that shall calculate the resistivity shift amount to carbon doping amount in a silicon single crystal wafer. A method for growing a silicon single crystal,
When a silicon single crystal is grown by doping carbon and a resistance adjusting dopant by the Czochralski method, a shift amount of resistivity generated with carbon doping is calculated in advance, and the doping amount of the resistance adjusting dopant is calculated. According to the method of adjusting according to the shift and calculating, the preliminary silicon single crystal is grown by doping carbon and a resistance adjusting dopant by the Czochralski method, and the preliminary silicon single crystal is sliced to prepare After processing into a silicon single crystal wafer, the resistivity and carbon concentration of the preliminary wafer are measured, and then the preliminary wafer is subjected to a heat treatment that simulates the heat treatment in the device process, and then the resistivity and the heat treatment preliminary wafer are measured. The carbon concentration is measured, and the amount of donor generated is determined from the amount of change in carbon concentration and the amount of resistivity of the preliminary wafer before and after the heat treatment. , From said relationship between the donor generation amount and the carbon concentration variation, features and to Cie method for growing a silicon single crystal that shall calculate the resistivity shift amount to carbon doping amount in a silicon single crystal wafer. After the silicon single crystal grown by the silicon single crystal growth method according to claim 1 or 2 is sliced and processed into a silicon single crystal wafer, an epitaxial layer is formed on the main surface of the wafer. A method for producing a silicon epitaxial wafer.

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