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Thermodynamics on SOG-Si

Refining Processes

Institute of Industrial Science,The University of Tokyo

Kazuki Morita

The 3rd Workshop on

Reactive Metal Processing

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Recent Research Fields

Physical Chemistry of High TemperatureProcessing (Steelmaking and Waste Management)

Microwave Processing for Recycling and WasteTreatment

Thermodynamics and Processing on Solar GradeSilicon (SOG-Si) Production

Materials Production and Recycling

Engineering Lab.(Formerly Ferrous Metallurgy Lab.)

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Contents

1. Introduction

2. Metallurgical refining for SOG-Si

- Thermodynamic properties of impurities in molten Si alloys -

- Optimized Process Combined with Leaching Treatment -

3. Solidification refining of Si with Si-Al metls

- Segregation ratios of impurities between solid Si and Si-Al melt -

4. Conclusions and Future Work

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Requirement for metallurgical refining process for SOG-Si

Depending on off-grade Si for semiconductor

Increase in solar cell production

90 91 92 93 94 95 96 97 98 99 1001011021031040

100

200300

400

500

600700

800

900

10001100

1200

Amountofproduction(MW)

YearFig. Amount of solar cell production by various processes.

Total

Poly Crystalline

Single Crystalline

AmorphousRibbon

00 01 02 03 04

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Possibility of Low Cost SOG-Si Production

Can we remove impurities from MG-silicon

by metallurgical refining processes ?

MG-Si SOG-Si

New Refining Process?

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Ti

Fe

P

Al

Fig. Solar-cell efficiency versus impurity concentration for

4-cm p-base devices.

Fe, Ti, Al, P, B

Impurtiry Content(ppma)

Fe 1300

Ti 220

Al 3300

P 30B 30

Table 1 Impurity

contents in MG-Si.

Impurities and solar cell efficiency

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-1600

-1200

-800

-400

0

0 500 1000 1500 2000 2500

4Cu+O2

=2Cu2O

2Fe+O2

=2FeO

2C+O2=2CO

C+O2=CO

2

3/2Fe+O2

=1/2Fe3

O4

2Mn+

O2=2MnO

Si+O2

=SiO2

4/3Ti+

O2=2/

3Ti2O3

4/3Al+

O2=2/

3Al2O3

2Mg+

O2=2Mg

O

2Ca+

O2=2

CaO

Temperature(K)

G ib

b s

e ne

rg y

o f

fo

rma t i

o n

fo r

o x i

d e s(k

J/ m

o l O

2)

-1600

-1200

-800

-400

0

0 500 1000 1500 2000 2500

4Cu+O2

=2Cu2O

2Fe+O2

=2FeO

2C+O2=2CO

C+O2=CO

2

3/2Fe+O2

=1/2Fe3

O4

2Mn+

O2=2MnO

Si+O2

=SiO2

4/3Ti+

O2=2/

3Ti2O3

4/3Al+

O2=2/

3Al2O3

2Mg+

O2=2Mg

O

2Ca+

O2=2

CaO

Temperature(K)

G ib

b s

e ne

rg y

o f

fo

rma t i

o n

fo r

o x i

d e s(k

J/ m

o l O

2)

Fe-FeO

Al-Al2O3

Mg-MgO

Ca-CaO

Si-SiO2

Fig. Ellingham diagram for some

representative elements.

Strong Affinity ofSilicon for Oxygen

=

Difficulty in

Oxidation Treatment

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Si Standard : solid Si standard : solid

GM solid

0 - 0- liquid

liquid solid

Component X Si

L

L T1

S+L

S+L S

Si Si

(a) Small segregation coefficient

Component XComponent X

Component X

T=T1

Si

GM

(b) Large segregation coefficient

T1

T=T1

Fig. Relationship between Gibbs free energy and phase diagram below

melting point of silicon.

P, B, C, etc.Most metallic

impurities

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10-6 10-5 10-4 10-3 10-2 10-1 10010-1110-1010-910-810-710-610-510

-410-310-210-1100101102103104

segregation coefficient

i

mpurityco

ntent(ppm

w) after first

solidification

after secondsolidification

Impurity content of MG-Si

Required impurity content for SOG-Si

Al

NiCr

Fe

V

Ti BP

Fig. Removal of impurity in silicon by solidification refining.

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Thermodynamic properties of

impurities in molten silicon alloys

PhosphorousEquilibrated in a controlled phosphorous partial pressure

Titanium and IronEquilibrated with lead

Aluminum, Calcium and MagnesiumEquilibrated with Oxides

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Thermodynamics of P in Molten Silicon

Gas Inlet Tube

Porous Alumina Block

Molten Si-P Alloy

Graphite or Alumina Crucible

Graphite Holder

Mullite Tube

Fig. Schematic Cross Section of Experimental Apparatus.

Ar+P4(P2+P)

To Ribbon Heater

Temperature Controller

Ar+P4

Thermocouple

SiliconePlug

Red Phosphorus Ribbon Heater

Ar

Red Phosphorus Temperature 398-461K

Argon Flow Rate 190cc/min

Fig. Schematic cross section of the phosphorus vapor generator.

To Ribbon Heater

Temperature Controller

Ar+P4

Thermocouple

SiliconePlug

Red Phosphorus Ribbon Heater

Ar

Red Phosphorus Temperature 398-461K

Argon Flow Rate 190cc/min

Fig. Schematic cross section of the phosphorus vapor generator.

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0.05 0.1

0.001

0.002

0[mass%P]

PP

1/2(atm1/2)

2

1750 1800 1850-80

-70

-60

-50

T(K)

Freeenergychange(kJ/mol)

1/2 P2(g)=P(mass%, in Si)G= -139,000+43.4T(J/mol)

Fig. Relationship between equilibrium

phosphorous partial pressure and

phosphorous concentration of silicon at

1823K.

Fig. Temperature dependence of

free energy change of phosphorous

dissolution into silicon.

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10-6 10-5 10-4 10-3 10-2 10-110-1610

-1510-1410-1310-1210-1110-1010

-910-810-710-610-510-4

[mass%P]

P

(atm)

P

P

P

P2P,

P

P2

1 2 3 4

0.01

0.02

0.03

0Time (ks)(V

/A)log([mass%P]0/[mass%P]t)(m

) Suzuki et al.estimated

Yuge et al.

1823K 1867K

Ikeda et al.

estimated

Fig. Relationship between equilibrium

partial pressure of P, P2 and phosphorouscontent of silicon at 1823K.

Fig. Relationship between time

for vacuum treatment and(V/A)

log([mass%P]0/[mass%P]t).

Hertz-Knudsen equation

iii

i

XpRT

M

dt

dy

=

0

2

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Gas Inlet Tube

Porous AluminaBlock

Graphite Crucible

Graphite Holder

Mullite Tube

Graphite Lid

Molten Si-M

(M:Fe,Ti)

Molten Lead

Fig. Phase diagram of Si-Pb system.

Thermodynamics of Ti and Fe in Molten Silicon

Si Pb

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0 0.02 0.04 0.06-6

-5

-4-3

-2

-1

XFe in Si

lnXFeinPb-lnXFein

Si-14.1

XPbinS

i

-23.8

XSiinPb+4.91

lnXFe in Pb-lnXFe in Si-14.1XPb in Si-23.8XSi in Pb+4.91

=-3.56(0.40)+3.17(5.46)XFe in Si

Fe(l) in Si=2.8510-2

FeFe

in Si=3.17

0 0.025 0.05 0.075 0.1-9

-8

-7

-6

XTi in Si

lnXTiinPb-lnXTiinSi-13.2

XPbin

Si

-10

.8XSiinPb-1.7

4

lnXTi in Pb-lnXTi in Si-13.2XPb in Si

= -7.71+3.97X

Ti in Si

Ti(l) in Si=4.4810-4

TiTi

in Si=3.97

-10.8XSi in Pb-1.74

Fig. Relationsip betweenXTi in Si andlnXPb in Pb lnXPb in Si at 1723K.Fig. Relationsip betweenXFe in Si andlnXPb in Pb lnXPb in Si at 1723K.

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Ti and Fe are stable in molten silicon.

Removal of Ti and Fe by chemical

reaction (i.e. oxidation, chlorination) is

considered to be impossible.

Double solidification process is required.

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Graphite

Holder

Al2O3-Al6Si2O13 Crucible

Molten Si-Al Alloy

SiO2 Crucible

Molten Si-Ca Alloy

Molten SiO2 satd.

CaO-SiO2 Slag

SiO2 Crucible

Molten Si-Mg Alloy

Molten MgSiO3, SiO2satd.MgO-SiO2-Al2O3 Slag

MgSiO3, SiO2pellet

Thermodynamics of Al, Ca and Mg in Molten Silicon

Al

Ca

Mg

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5.4 5.6 5.8

-1

-0.8

-0.6

-0.4

-0.2

0

-3.6

-3.4

-3.2

-3

-2.8

-2.6

104/T(K-1)

logAl(l),

logMg(l)

logCa(l)

Ca

Mg

Al

172317731823

T(K)

Fig. Temperature dependence of the activity coefficient of aluminum,

calcium, and magnesium in molten silicon relative to pure liquid.

51.411300ln

55.114300

ln

452.03610ln

Ca

Al

+=

+=

+=

T

T

T

Mg

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1 2 3 4 5 6

10

20

30

0

1000

2000

3000

0

P

Ca

Al

Fig. Relationship between vacuum time and impurity content of silicon at 1823K.

Time(ks)

massppmP

mass

ppmAl,massppmCa

0.739m2

40.3m2

mass of Si : 1000kg

surface area

P, Al, Ca and Mg can be

removed by vacuum melting.

Mg

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Vacuum melting by electron beam

Vacuum

Plasma melting with water vapor

Directional solidification

MG-Si

ArgonSOG-Si

Removal of P, (Al, Ca) Removal of B, C

Removal of Fe,Ti,Al

First step purification Second step purification


Removal of Fe,Ti,Al

Lower cost refining process is desired to be developed

NEDO SOG-Si Manufacturing Process

(Operated in JFE Steel Co.)

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Is there any way to reduce the timesof solidification refining?

If the treatment of MG-Si can

remove 90% of Ti and Fe,

Possibility of Acid Leaching

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Si-Ca-Fe or Ti

dissolved at 1723K

Cooling to 1300K

(CaSi2 formation)

Acid leaching with

aqua regia

Chemical analysis

Acid Leaching Test with Ca Addition

Porous Alumina

Block

Graphite Crucible

Graphite HolderAr

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Removal Fraction of Fe

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Fig. Phase Diagram of the Si rich corner for theCa-Fe-Si System [calculated by Thermo-Calc]

Eutectic Point

XCa/XFe6.4

Secondary Phase

CaSi2 or FeSi2 ?

Consideration of Removal Behavior of

Fe with the Ca-Fe-Si Phase Diagram

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Fig.

(a) SEM micrograph of Si-Ca-Fe alloy.

(b) Microstructure of Si-Ca-Fe alloy.

(c) Concentration profile by EPMA line analysis.

Si-3.26%Ca-0.424%Fe, 4.4K/min

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Fig.

(a) SEM micrograph of Si-Ca-Fe alloy.

(b) Microstructure of Si-Ca-Fe alloy.

(c) Concentration profile by EPMA line analysis.

Si-2.41%Ca-0.685%Fe, 4.4K/min

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Vacuum



MG-Si

Argon

SOG-Si

Removal of P, (Al, Ca) Removal of B, C, (Al, Ca)

Removal of Fe,Ti,Al



Removal of Fe,Ti,Al



P : 30 < 0.1ppmw B : 5-10 0.1-0.3 ppmw

Acid leaching treatment with Ca addition

Removal of Fe and Ti

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Vacuum



MG-Si

Argon

SOG-Si

Removal of P, (Al, Ca) Removal of B, C, (Al, Ca)

Removal of Fe,Ti,Al



Removal of Fe,Ti,Al



P : 30 < 0.1ppmw B : 5-10 0.1-0.3 ppmw

Acid leaching treatment with Ca addition

Removal of Fe, Ti, P and B

Reduction of

processing time

Phase diagrams for the Si-Al system

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Solidification refining of Si with Si-Almelt at low temperature.

Low eutectictemperature

Fig. Phase diagram of Si-Al system.

Removal of impurities byuse of enhanced segregationat low temperature

Phase diagrams for the Si Al system

MG-Si

(98-99%)Pure Al

Segregation ratiomeltAlSiini

Sisolidini

iX

Xk

=

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Segregation ratios of impurities

between solid Si and Si-Al melt

Thermodynamics of impurity elements in solid Si

Evaluation of low temperature Si refining process

Segregation ratios of impurities between Si-Al melt and solid Si

Al, B, P

Fe,Ti, etc.

Experimentally determined

Theoretically determined

Determination for segregation ratios of P and B

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Fig. Diffusion coefficient of impurity elements in solid silicon.

Al, P, B Considerably smalldiffusion coefficient in solid Si

Solidification method to

attain the equilibrium

Diffusion coefficient of impurity elements in solid Si


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1 2

Solid Si

Si-Al melt

Solid Si

T2

T1

Tm,A

C1sC1

l C2l C2

s A

Component B

Distance

a) b)

T

emp.

LS

L+S

Fig. Schematic diagrams of the temperature gradient zone melting.

(a) Portion of phase diagram. (b) Temperature gradient in system.(c) Physical system comprising (A+B)molten zone traveling through solid A.

c)

Temperature Gradient Zone Melting(TGZM) method

Precipitated Si


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Temperature Gradient Zone Melting MethodAl and P contents in solid silicon -

EPMA analysisAr atmosphere 24-72h

Temperature Gradient 10-40K/cm

1

2

3

4

5 6 8

10

11

97

12

Fig. 1. Schematic diagram of an experimental apparatus: 1-SiC heating element; 2-thermocouple

connected to PID controller; 3-gas outlet tube; 4-stainless steel holder; 5-single crystalline silicon; 6-aluminum foil; 7-mullite tube; 8-thermocouple for measuring temperature of molten zone; 9-porous

alumina boat 10-gas inlet tube; 11-alumina plate; 12-Sponge titanium

Distribution of P (and Al) between

solid Si and Si-Al-P alloy

- Red phosphorus stuck Al foil

Distribution of B (and Al) between

solid Si and Si-Al-B alloy

- Prepared Al-B foil

Experimental method


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Fig. Photo of a TGZM specimen after

the experiment.

10mm

B A

Fig. Intensity profiles of Ka radiation of aluminum and

phosphorus of the sample (accelerating voltage of 15kV,sample current of 200nA, sampling step of 10m).

100 200 300 400 500 600

100

200

300

400

0

Distance (m)

IntensitiesofK

radiationof

alu

minumandphosphorus

PAl

(a) Single crystalline Si (d) Single crystalline Si(c) Si-Al zone

(b) Migrated region

Segregation ratio

Sample after TGZM experiment

Segregation ratios of P and B

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Segregation ratios of P and B

1200 1400 16000.01

0.05

0.1

0.5

1

5

Temperature (K)

Se

gregationratio

P

B

Segregation ratios are smaller at low temperature.

Low temperature refining is effective.

Segregation ratio between

solid Si and Si-Al melt

Segregation coefficient

between solid/liquid Si.

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s

i

s

i

l

i

l

i aRTGaRTG lnln00+=+

0

0

lnlnlns

i

l

i

fus

i

l

i

s

i

iRT

G

X

Xk

+

==

Equality in chemical potential of impurity between solid Si

and Si-Al melt

1)

2)

Activity coefficients in solid Si and Si-Al melt

Based on the reported thermodynamic data

Derivation of segregation ratio of impurity

elements between solid Si and Si-Al melt

Segregation ratios between solid Si and Si-Al melt

< S ti ffi i t b t lid/li id Si

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< Segregation coefficients between solid/liquid SiSegregation ratio between Si-Al me lt

and solid SiElement

1073K 1273K 1473K

Segregation coefficient

between solid/liquid Si at

m.p. of Si(6-3)

Fe 1.710 -11 5.910 -9 3.010 -7 6.410 -6

Ti 3.810 -9 1.610 -7 9.610 -7 2.010 -6

Cr 4.910 -10 2.510 -8 2.510 -7 1.110 -5

Mn 3.410 -10 4.510 -8 9.910 -7 1.310 -5

Ni 1.310 -9 1.610 -7 4.510 -6 1.310 -4

Cu 9.210 -8 4.410 -6 2.510 -5 4.010 -4

Zn 2.210 -9 1.210 -7 2.110 -6 1.010 -5

Ag 1.910 -8 1.710 -6 6.610 -6 5.010 -5

Au 1.510 -11 6.110 -9 3.610 -7 2.510 -5

Ga 2.110 -4 8.910 -4 2.410 -3 8.010 -3

In 1.110 -5 4.910 -5 1.510 -4 4.010 -4

Sb 3.410 -3 3.710 -3 8.210 -3 2.310 -2

Pb 9.710 -5 2.910 -4 1.010 -3 2.010 -3

Bi 1.310 -6 2.110 -5 1.710 -4 7.010 -4

P 4.010 -2 8.510 -2 1.610 -1 3.510 -1

B 7.610 -2 2.210 -1 4.910 -1 8.010 -1

Al 1.410 -4 4.910 -4 1.210 -3 2.810 -3

Impurity contents of Si after low temperature

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10-6

10-5

10-4

10-3

10-210

-1

100

101

102

103

Contents of MG-Si Allowable contents for SOG-SContents after solidification refining with Si-Al meltContents after ordinary solidification refining

Impurityco

ntent(ppmw

)

Fe Ti P B

Impurity contents of Si after low temperature

solidification refining with Si-Al melt at 1273K and

ordinary Si solidification refining of MG-Si.

Contents after purification; Ci =ki Ciini Initial content

(MG-Si)at 1273K

Si

Viewing the development of the solidification

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refining of Si with Si-Al melt at low temperature

Fig. Phase diagram of Si-Al system.

Si bathAl bath

Si-Al melt

Poly or Single Crystalline ?

Discussion of the Si solidification method

from Si-Al melt

Refining test

Discussion for separating of solid Si from Si-Al

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melt by flotation

Holding Si-55.3at%Al alloy (liquidus temp. 1273K) at 1173K for 12h

Si saturated, solid fraction = 0.168

Needle like Si grains

Preparation Melting in the

induction furnace and rapid cooling

(solid Si < 2.33g/cm3, Al-25.8%Si 2.45g/cm3)

Separation of solidified Si from Si-Al

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p

melt using electromagnetic force Induction furnace1

3

7

12

11

54 6

8

109

2

Si-55.3at%Al alloy (liquidus,1273K) was melted and held at

1323K in the induction furnace

Measuring the surfacetemp. of the melt by

the infrared pyrometer

Cooling and Solidifying the

sample by lowering from the

position of induction coil

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Solidified Si-Al alloy using

induction furnace

Agglomeration of solidified Si by electromagnetic stirring

Bottom

1cm

Agglomeration mechanism of Si under

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Si-Al melt Solidified Si

Inductioncoil

J

B

J

BInduced flow

F

Difference in inducedswirl current to the

perpendicular direction

Solidification of Si at lower

position

Downward bulk flowAgglomeration of Si grainsto the bottom of the sample

gg

the fixed alternative magnetic field

Solidification refining test

Experimental method Synthesized MG-Si was alloyed to Si-

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Fig. Schematic cross section ofexperimental apparatus.

Alumina block

Gas inlet tube

Induction coil

Graphite crucible

Quartz tube

Prism

Molten alloy

Melting and holding at 1323K

or 1223K

Cooling and solidifying the sampleby lowering from the coil

Measuring the surface temp.

by infrared pyrometer

p

Crashing the Si agglomerated part

(> 840m), then acid cleaningSample No. Fe Ti Al B P

PrSi-1 4500 691 1280 56 36

PrSi-2 2160 248 1560 36 19

Synthesized MG-Si was alloyed to Si-

55.3at%Al(liquidus, 1273K) or Si-64.6

at%Al(liquidus, 1173K) with pure Al

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Sample No Source Fe Ti B P Al

SR-1 PrSi-1 13 (99.7%) 5.2 (99.2%) 0.81 (98.6%) 0.93 (97.4%) 599 (53.1%)

SR-2 PrSi-1 13 (99.7%) 2.7 (99.6%) 0.88 (98.4%) 1.2 (96.7%) 534 (58.1%)

SR-3 PrSi-2 20 (99.1%) 2.8 (98.9%) 0.71 (98.1%) 0.72 (96.3%) 575 (63.1%)

SR-4 PrSi-2 27 (98.8%) 4.5 (98.2%) 1.90 (94.8%) 1.0 (95.1%) 602 (61.3%)

SR-5 PrSi-1 47 (99.0%) 7.7 (98.9%) 0.98 (98.3%) 0.42 (98.8%) 538 (57.8%)

SR-6 PrSi-1 36 (99.2%) 5.6 (99.2%) 0.99 (98.2%) 0.66 (98.2%) 453 (64.5%)

Fe, TiWell reduced but not as well as predicted valuesB, P Effectively removed

Impurity contents of refined Si in the test run (ppmw)

High ability for purification was confirmed.

Proposal of refining process for SOG-Si

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Reduction of SiO2 in arc furnace

Removal of P, (Al, Ca)

Removal of Fe,Ti,Al


Alloying of silicon with Al

SOG-Si

Solidification refining with Si-Al melts

Pre-refined Si (5N except Al)

Proposal of refining process for SOG Si

Acid cleaning

C l i d F t W k

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Conclusions and Future Work

The optimum metallurgical refining

process for SOG-Si was thermodynamicallyassessed.

Possibility of solidification refining of Si

with Si-Al melt was clarified. Solidification

and separation of Si from the melt is the

major problem to solve for the practical

process.

A k l d t

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Acknowledgments

Present data are based on two Doctoral

Dissertations by Takahiro Miki (1999),now a research associate of Tohoku

University, and Takeshi Yoshikawa(2005), now an assistant professor of

Osaka University.

Periodical Journal Publication List 1

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Metallurgical Refining

T.Miki, K.Morita and N.Sano :Metallurgical and Materials Transactions B, 27B(1996),937-942, Thermodynamics of Phosphorus in Molten SiliconT.Miki, K.Morita and N.Sano :Metallurgical and Materials Transactions B, 28B(1997),861-867, Thermodynamic Properties of Titanium and Iron in Molten SiliconT.Miki, K.Morita and N.Sano :Metallurgical and Materials Transactions B, 28B(1997),861-867, Thermodynamic Properties of Titanium and Iron in Molten SiliconT.Miki, K.Morita and M.Yamawaki :Journal of the Mass Spectrometry Society ofJapan47(1999), 72-75, Measurements of Thermodynamic Properties of Iron in MoltenSilicon by Knudsen Effusion MethodT.Miki, K.Morita and N.Sano :Materials Transactions, JIM, 40 (1999), 1108-1116,Thermodynamic Properties of Si-Al, -Ca, -Mg Binary and Si-Ca-Al, -Ti, -Fe TernaryAlloys 66(2002), 459-465, K.Morita and T.Miki :Intermetallics, 11(2003), 1111-1117, Thermodynamics on Solar-Grade-Silicon RefiningG.Inoue, T.Yoshikawa and K.Morita :High Temperature Materials and Processes,22(2003), 221-226, Effect of Calcium on Thermodynamic Properties of Boron in MoltenSiliconT.Shinpo, T.Yoshikawa and K.Morita :Metallurgical and Materials Transactions B,35B(2004), 277-284, Thermodynamic Study of the Effect of Calcium on Removal ofPhosphorus from Silicon by Acid Leaching Treatment

Periodical Journal Publication List 2

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Solidification Refining

T.Yoshikawa and K.Morita :J.Electrochem. Soc., 150(2003), G465-G468, SolidSolubilities and Thermodynamic Properties of Aluminum in Solid Silicon

T.Yoshikawa and K.Morita :Science and Technology of Advanced Materials, 4(2003), 531-537, Removal of Phosphorus by the Solidification Refining with SiAl Melts

T.Yoshikawa and K.Morita :Journal of Physics and Chemistry of Solids, 66(2005), 261-265,Thermodynamics of Solid Silicon Equilibrated with Si-Al-Cu Liquid AlloysT.Yoshikawa and K.Morita :Materials Transaction, 46(2005), 1335-1340,Thermodynamic Property of B in Molten Si and Phase Relations for the Si-Al-B SystemT.Yoshikawa and K.Morita :ISIJ International, 45(2005), 967-971, Refining of Si by theSolidification of Si-Al Melt with Electromagnetic ForceT.Yoshikawa and K.Morita :Metallurgical and Materirals Transactions B, 36B(2005), 731-736, Removal of B from Si by the Solidification Refining with SiAl MeltsT.Yoshikawa, K.Arimura and K.Morita :Metallurgical and Materirals Transactions B,36B(2005), 837-842, B Removal by Ti Addition in the Solidification Refining of Si with SiAl MeltsT.Yoshikawa and K.Morita :Journal of Alloys and Compounds, 420(2006), 136-144Activity Measurements of Al and Cu in Si-Al-Cu Melt at 1273 and 1373 K by theEquilibration with Molten Pb

RMW3 08 Morita H

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