CN101994152A - Process for manufacturing solar crystalline silicon P-type master alloy - Google Patents

Abstract

The invention discloses a process for manufacturing a solar crystalline silicon P-type master alloy. The weight and the resistivity of a boron-doped silicon material with low resistance are measured; the concentration of a doping agent of the low-resistance silicon material is calculated; the weight equivalent to target resistivity is calculated according to a formula (2); conversion can be also performed according to an attached list 1 formed by calculating through the formula; and then master alloys with different resistivity have the equivalent weight of master alloys with certain resistivity. Compared with the prior art, the invention has the characteristics of simple process method, accurate resistivity control and capability of fully using the boron-doped silicon material with low resistance and reducing the production cost.

Description

The production technique of solar level crystalline silicon P type mother alloy

Technical field

What the present invention relates to is a kind of production technique of solar level crystalline silicon P type mother alloy.

Background technology

When producing the solar level crystalline silicon material, the control of its resistivity is to realize by the mother alloy of specific electric resistance at present.Throw stove 60kg such as CZ silicon single crystal, the resistivity that drops into material is 20 Ω CM, and model is the P type, and produce the crystal bar head resistivity is 1.5 Ω CM, and model is the silicon rod of P type, is that the boron-doping mother alloy of 0.0065 Ω CM need drop into 48.4 grams as dropping into resistivity.

The method of producing mother alloy at present in the industry mainly is a resistivity stepping method.Be about to the heavily doped silicon material of P type resistivity and be divided into some shelves, measure heavily doped resistivity afterwards, assign to corresponding gear.As:

0.001-0.002Ω·CM

0.002-0.003Ω·CM

0.003-0.004Ω·CM

0.005-0.006Ω·CM

……………………

0.009-0.01Ω·CM

0.011-0.012Ω·CM

……………………

Because along with the increase of resistivity, stepping is more and more, and the heavily doped silicon material of P type resistivity distribution is generally wider, this makes and adopts the mother alloy resistivity distribution of produced in conventional processes wide, inaccurate.

Summary of the invention

The object of the present invention is to provide a kind of technology of the P type mother alloy that can produce.

The invention solves current mother alloy and make inaccurate, the low low problem of resistance material utilization ratio.This technology is that boron-doping low-resistance silicon material is carried out the measurement of weight and resistivity, calculates the concentration of dopant of low-resistance silicon material.Calculate the weight of equivalent target resistivity according to formula; The table that the present invention also can calculate and be made according to described formula, easy-to-look-up; The mother alloy of different resistivity has the equivalent weight of a certain resistivity mother alloy by the adjustment of weight; The present invention compared with prior art, it is simple to have processing method, the resistivity precise control can make full use of low-resistance boron-doped silicon material, the characteristics that reduce production costs.

Description of drawings

Fig. 1 is the weight ratio figure under the different mother alloy same effect.

Embodiment

One, the boron-doping low-resistance silicon material of preparation being made the different resistivity of mother alloy carries out weight W ₁And electricalresistivity ₁Measurement, according to the electricalresistivity of the boron-doping low-resistance silicon material of measuring gained ₁Electricalresistivity with the known target mother alloy ₂, mix the formula (1) of phosphorus single crystal silicon resistivity and concentration of dopant conversion rules according to the GB/T13389-1992 boron-doping, calculate the concentration of dopant N (ρ of low-resistance silicon material ₁) and target mother alloy concentration of dopant N (ρ ₂), formula (1) is as follows:

$N_{\left(p\right)}=\frac{1.33{\mathrm{<figure-callout\; id="10"\; label="X"\; filenames="DEST\_PATH\_HSB00000052643800011.png"\; state="\{\{state\}\}">X</figure-callout>}10}^{16}}{\mathrm{\&rho;}}+\frac{1.082\mathrm{<figure-callout\; id="10"\; label="X"\; filenames="DEST\_PATH\_HSB00000052643800011.png"\; state="\{\{state\}\}">X</figure-callout>}{10}^{17}}{\mathrm{\&rho;}[1+{\left(54.56\mathrm{\&rho;}\right)}^{1.105}]}$ Formula (1)

-----resistivity Ω cm in the formula: ρ; N----concentration of dopant cm ^-3

Two, the preparation that provides according to formula (2) the low-resistance silicon material of making mother alloy and target mother alloy reach the weight ratio of identical boron content, converse and prepare to make the weight W of the low-resistance silicon material equivalence of mother alloy to the target mother alloy ₂, when needs mix, according to W ₂The weight and the resistivity of target mother alloy mix and get final product, formula (2) is as follows:

$\frac{W_1}{W_2}=\frac{N\left({\mathrm{\&rho;}}_2\right)}{N\left({\mathrm{\&rho;}}_1\right)}$ Formula (2)

Wherein: the resistivity of mother alloy 1 (boron-doping low-resistance silicon material) is ρ ₁

The resistivity of mother alloy 2 (target mother alloy) is ρ ₂

The concentration of mother alloy 1 (boron-doping low-resistance silicon material) doping agent is

The concentration of mother alloy 2 (target mother alloy) doping agent is

The weight of mother alloy 1 (boron-doping low-resistance silicon material) is W ₁

The weight of mother alloy 2 (target mother alloy) is W ₂

Formula (2) is K in charging capacity simultaneously ₀" W ₁, W ₂, crystal polarity is P type, electricalresistivity ₃" ρ ₁, ρ ₂Situation under more accurate.

Embodiment 1, and if any 5 low-resistance boron-doping silicon chips, the parameter of gained is after calculating:

First weight is 10 grams, and resistivity is 0.0255 Ω CM;

Second weight is 10 grams, and resistivity is 0.0632 Ω CM;

The 3rd weight is 10 grams, and resistivity is 0.0134 Ω CM;

The 4th weight is 10 grams, and resistivity is 0.0014 Ω CM;

The 5th weight is 10 grams, and resistivity is 0.0035 Ω CM;

According to the weight that can calculate equivalent mother alloy with following formula (1) and formula (2) be:

The mother alloy weight that first equivalent resistivity is 0.0065 Ω CM is 1.54 grams;

The mother alloy weight that second equivalent resistivity is 0.0065 Ω CM is 0.38 gram;

The mother alloy weight that the 3rd equivalent resistivity is 0.0065 Ω CM is 3.90 grams;

The mother alloy weight that the 4th equivalent resistivity is 0.0065 Ω CM is 56.24 grams;

The mother alloy weight that the 5th equivalent resistivity is 0.0065 Ω CM is 20.74 grams;

When throwing, feed intake afterwards and get final product according to the boron-doping mother alloy of 0.0065 Ω CM and equivalent weight.According to the accurate controlling resistance rate of this technology, effectively use boron-doping low-resistance silicon material, be example with the factory of 100 single crystal growing furnaces, the low resistance material of the boron-doping that consume every month just can reach more than hundred kilograms, amounts to cost and is reduced in more than 100,000 yuan.And present domestic solar energy single crystal, polycrystalline furnace surpass 3000, and this invention will be created the benefit of annual more than one hundred million units.

In the specific implementation process, the surface treatment of low-resistance boron-doped silicon material is clean, reach the service requirements of solar energy level silicon material single crystal growing furnace.

Embodiment 2: the present invention also can be made into following Fig. 1 specially according to aforesaid formula (1) and formula (2), to every boron-doping low-resistance silicon material measured resistivity and weight, carries out computing according to Fig. 1, provide equivalent a certain resistivity mother alloy weight, use feeds intake.

Fig. 1 is as follows.

Claims (1)

1. the production technique of a solar level crystalline silicon P type mother alloy, its feature is made up of following steps: one, the boron-doping low-resistance silicon material of preparing to make the different resistivity of mother alloy is carried out weight W ₁And electricalresistivity ₁Measurement, according to the electricalresistivity of the boron-doping low-resistance silicon material of measuring gained ₁Electricalresistivity with the known target mother alloy ₂, mix phosphorus single crystal silicon resistivity and concentration of dopant conversion rules according to GB/T 13389-1992 boron-doping, calculate the concentration of dopant N (ρ of low-resistance silicon material ₁) and target mother alloy concentration of dopant N (ρ ₂); Two, the preparation that provides according to formula (2) the low-resistance silicon material of making mother alloy and target mother alloy reach the weight ratio of identical boron content, converse and prepare to make the weight W of the low-resistance silicon material equivalence of mother alloy to the target mother alloy ₂, when needs mix, according to W ₂The weight and the resistivity of target mother alloy mix and get final product, formula (2) is as follows:

$\frac{W_1}{W_2}=\frac{N\left({\mathrm{\&rho;}}_2\right)}{N\left({\mathrm{\&rho;}}_1\right)}$ Formula (2)

Wherein: the resistivity of mother alloy 1 (boron-doping low-resistance silicon material) is ρ ₁

The resistivity of mother alloy 2 (target mother alloy) is ρ ₂

The concentration of mother alloy 1 (boron-doping low-resistance silicon material) doping agent is

The concentration of mother alloy 2 (target mother alloy) doping agent is

The weight of mother alloy 1 (boron-doping low-resistance silicon material) is W ₁

The weight of mother alloy 2 (target mother alloy) is W ₂

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