Application of Electron Beam Melting to the Removal of Phosphorus from Silicon: Toward Production of Solar-Grade Silicon by Metallurgical Processes

Table 2

Previous research on removal of P by EB melting.

	EB power/kW	Weight of Si sample/kg (or supply rate)	Temperature/K	Chamber pressure/Pa	P content in ppm (time)	Apparent mass transfer coefficient, 𝐾1/m s^−1
Ikeda and Maeda (1992) [6]	3.8~6.5	0.05	1867~1967	10^−3∼10^−2	38~45→ 3 (900 s)
Hanazawa et al. (2003, 2004) [22, 23]
(i) Batch process in laboratory scale	30~100	1.2~6.6	1950~2300	1.3~6.7×10^−2	30→0.05-0.06 (2200 s)
(ii) Batch process in industrial scale	190, 210	45		2.7~8.0×10^−2
(iii) Continuous process in laboratory scale	80	2~12 kgh^−1 (supply rate)		1.3~6.7×10^−2	25–30→0.3 (4600 s)
(iv) Continuous process in industrial scale	220, 250	16–70 kgh^−1 (supply rate)		1.3~8.0×10^−2	25–30→0.1 (4200 s)
Pires et al. (2003) [24]
Observation of segregation	14–17	0.28 (powder)	NA	10^−4∼10^−2	?→0.28–5.5 (1200 s)
Pires et al. (2005) [25]	15–17	0.28 (powder)	NA	10^−4∼10^−2	23→0.41 (1200 s)
		0.28 (massive)			38→0.39 (1200 s)
Miyake et al. (2006) [20]
Glow discharge EB	2.6~4.8	0.04	1850	5~7	140~230→1 (3600 s)
Kemmotsu et al. (2011) [19]
(i) Water-cooled Cu crucible	2.6	0.04	1860	10^−2	87→2.9 (1800 s)	2.0×10^−5 (1860 K)
(ii) Graphite crucible	2.6	0.04	1980	10^−2	166→0.9 (1800 s)
(iii) Graphite crucible	4.8	0.04	2520	10^−2	62→5.2 (180 s)
(iv) Stirred by Ar bubbling					37→10 (90 s)
(v) 0.1% O2-H2 blowing					37→9.4 (90 s)
(vi) 0.1% O2-H2 bubbling					37→1.5 (180 s)
(vii) Glow discharge EB	4.8	0.04	1860	1	106→5.2 (900 s)
Luo et al. (2011) [26]	10–15	0.4	NA	2.5~5.0×10^−3	20→1 (1200 s)
Jiang et al. (2012) [27]
Candle melting	6	0.7	NA	2×10^−3	144→ 60 (300 s)
Mei et al. (2012) [28]	11~13	0.2	NA	10^−3	50→1.8 (20 min melting followed by zone melting)	—
Liu et al. (2012) [29]
Industrial scale	350	500	NA	10^−3	15→0.07	—
Tan et al. (2013) [30]	21	0.3	2001	10^−3	16→0.16 (1400 s)
	9	0.3	1941	0.5~5×10^−2		1.07×10^−5 (1941 K)
Shi et al. (2013) [31]	15		1964			1.44×10^−5 (1964 K)
	21		2051		3320→7 (1920 s)	2.59×10^−5 (2051 K)
Choi et al. (2013) [32]	12	0.25		1×10^−2	34→4.5 (2640 s)