Solar silicon via improved and expanded metallurgical silicon technology. Quarterly report No. 5

Technical Report · Sat Oct 01 00:00:00 EDT 1977

DOI:https://doi.org/10.2172/5290693· OSTI ID:5290693

Hunt, L. P.; Dosat, V. D.; McCormick, J. R.

The goal of this program is to produce solar-cell-grade silicon at 3000 Mt/y for less than $10/kg by 1986. The approach is to improve upon and merge two already existing commercial technologies: the arc-furnace method of producing $1/kg, 98-% pure metallurgical silicon and the Czochralski crystal-growth technique used in the semiconductor industry. Arc-furnace silicon has been produced with difficulty by smelting high-purity quartz with purified charcoal. After further purification using the Czochralski technique, the best silicon had 9 ppma boron (0.1 ohm-cm), 12 ppma phosphorus, and less than 1 ppma aluminum. The boron goal of 0.3 ohm-cm has been more closely approached. Phosphorus must be lowered due to its resistivity compensation effect. Solar cells prepared on 0.09-ohm-cm material have shown conversion efficiencies 90% of that of control cells fabricated by Spectrolab. The most probable cost of this SoG-Si process was estimated to be $8.25/kg Si for manufacturing and $17.10/kg for capital at the 3000 Mt/y rate.

• Research Organization: Dow Corning Corp., Hemlock, Mich. (USA). Solid-State Research and Development Lab.
• DOE Contract Number: NAS-7-100-954559
• OSTI ID: 5290693
• Report Number(s): ERDA/JPL/954559-77/3
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
36 MATERIALS SCIENCE
SILICON
CRYSTAL GROWTH
PURIFICATION
SILICON SOLAR CELLS
FABRICATION
ARC FURNACES
CHARCOAL
COST
CZOCHRALSKI METHOD
EFFICIENCY
IMPURITIES
MANUFACTURING
PRODUCTION
QUARTZ
SMELTING
ADSORBENTS
CHALCOGENIDES
DIRECT ENERGY CONVERTERS
ELEMENTS
FURNACES
OXIDES
OXYGEN COMPOUNDS
PHOTOELECTRIC CELLS
PHOTOVOLTAIC CELLS
SEMIMETALS
SILICON COMPOUNDS
SILICON OXIDES
SOLAR CELLS
140501* - Solar Energy Conversion- Photovoltaic Conversion
360601 - Other Materials- Preparation & Manufacture