Electronic-grade silicon (EGS or EG-Si) or semiconductor-grade silicon (SGS) is a highly-purified version of the metallurgical-grade silicon with extremely low impurities suitable for microelectronic device applications. Electronic-grade silicon is the raw material used for the growth of single-crystal silicon in the manufacturing of silicon wafers.

Overview

While pure silicon (referred to as metallurgical-grade silicon) is of very good quality, it is still unsuitable for electronic device fabrication. Even impurities in the order of parts per million or less have significant impact on carrier mobility, reliability, and other aspects of the microelectronic device.

Impurity Concentrations in MG-Si (ppm)
Element	Concentration		Element	Concentration
Al	1000-5000		B	35-50
P	20-50		Ca	250-600
Cr	50-200		Cu	15-60
Fe	1600-6500		Mn	50-100
Mo	2-20		Ni	20-100
Ti	150-300		V	50-250
Zr	20-30

Metallurgical-grade silicon must be furthered purified to levels of usually less than a part per billion in order to be called electronic-grade silicon which can be used in subsequent fabrication steps.

Impurity Concentrations in EG-Si (ppb)
Element	Concentration		Element	Concentration
B	≤ 0.1		C	50-1000
Cr	≤ 0.01		Co	≤ 0.01
Cu	≤ 0.1		Fe	0.1 - 1
Ni	0.1 - 0.5		O	100-500
P	≤ 0.5		Zn	≤ 0.1