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Title: Mobil Solar Energy Corporation thin EFG octagons. Final subcontract report, 1 April 1992--31 January 1994

Technical Report ·
DOI:https://doi.org/10.2172/10161132· OSTI ID:10161132
 [1]
  1. Mobil Solar Energy Corp., Billerica, MA (US)

Mobil Solar Energy Corporation manufactures photovoltaic modules based on its unique Edge-defined Film-fed Growth (EFG) process for producing octagon-shaped hollow polycrystalline silicon tubes. The octagons are cut by lasers into 100 mm x 100 mm wafers which are suitable for solar cell processing. This process avoids slicing, grinding and polishing operations which are wasteful of material and are typical of most other wafer production methods. EFG wafers are fabricated into solar cells and modules using processes that have been specially developed to allow scaling up to high throughput rates. The goals of the Photovoltaic Manufacturing Technology Initiative (PVMaT) program at Mobil Solar were to improve the EFG manufacturing line through technology advances that accelerate cost reduction in production and stimulate market growth for its product. The program was structured into three main tasks: to decrease silicon utilization by lowering wafer thickness from 400 to 200 {mu}m; to enhance laser cutting yields and throughput while improving the wafer strength; and to raise crystal growth productivity and yield. The technical problems faced and the advances made in the Mobil Solar PVMaT program are described. The author concludes with a presentation of the results of a detailed cost model for EFT module production. This model describes the accelerated reductions in manufacturing costs which are already in place and the future benefits anticipated to result from the technical achievements of the PVMaT program.

Research Organization:
National Renewable Energy Lab. (NREL), Golden, CO (United States)
Sponsoring Organization:
USDOE, Washington, DC (US)
DOE Contract Number:
AC02-83CH10093
OSTI ID:
10161132
Report Number(s):
NREL/TP-411-6770; ON: DE94011829; BR: WM1020000; TRN: US200319%%234
Resource Relation:
Other Information: Supercedes report DE94011829; PBD: Jun 1994; PBD: 1 Jun 1994
Country of Publication:
United States
Language:
English