Chemistry: electrical and wave energy – Apparatus – Electrolytic
Reexamination Certificate
2005-11-15
2005-11-15
Pert, Evan (Department: 2826)
Chemistry: electrical and wave energy
Apparatus
Electrolytic
C216S099000, C438S508000
Reexamination Certificate
active
06964732
ABSTRACT:
A method and apparatus for slicing a semiconductor substrate. In one embodiment, the invention allows repetitive etching of a surface of the semiconductor substrate with a time dependent concentration of fluorine ions and a time dependent current I, such that multiple porous layers are obtained. The porous layer is released, and the released porous layer is removed from the surface of the substrate. The surface roughness of the porous layer is maintained within an acceptable or desired level of roughness value. The invention also provides an apparatus including a container having an etching solution. The semiconductor substrate may be protected by a tube covering at least a potion of said semiconductor substrate from said etching solution. The rate of insertion of said semiconductor substrate into the container is controlled to synchronize the lift-off with the insertion of the correct thickness of the semiconductor substrate. The anodising current is provided between two electrodes during operation.
REFERENCES:
patent: 5206523 (1993-04-01), Goesele et al.
patent: 6326280 (2001-12-01), Tayanaka
patent: 6331208 (2001-12-01), Nishida et al.
patent: 6350702 (2002-02-01), Sakaguchi et al.
patent: 6649485 (2003-11-01), Solanki et al.
patent: 0 226 091 (1987-06-01), None
patent: 0 797 258 (1987-09-01), None
patent: 0 975 012 (2000-01-01), None
Solanki et al., “Thin Monocrystalline Silicon Films for Solar Cells,” May 2003, 3rd World Conference on Photovoltaic Energy Conversion, pp. 1320-1323.
Bender, et al., “Morphological properties of porous-Si layers for n+-emitter applications”, Applied Surface Science, vol. 47, pp. 187-200), (1999).
Billat, et al., “Influence of etch stops on the microstructure of porous silicon layers”, Thin Solid Films, vol. 297, pp. 22-25, (1997).
Ookubo, et al., “Microscope observation of a self-standing film of porous silicon”, Materials Science and Engineering, vol. B20, pp. 324-327, (1993).
Rinke, et al., “Quasi-monocrystalline silicon for thin-film devices”, Applied Physics A, 68, pp. 705-707, (1999).
Tayanaka, et al., “Thin-film crystalline silicon solar cells obtained by separation of a porous silicon sacrificial layer”, 2ndWold Conference and Exhibition on Photovoltaic Solar Energy Conversion, Vienna, Austria, 1272 (Jul. 6-10, 1998).
European Search Reports for European Application No. EP 00 87 0040, dated Aug. 28, 2000.
Solanki, et al., Effect of the composition of electrolyte on separation of porous silicon film by electrochemical etching, Phys. Stat. Sol. (a) 197 (2), pp. 507-511, May 26, 2003, Wiley-VCH Verlag GmbH & Co., KGaA, Weinheim.
Bilyalov, et al., Role of hydrogen in the separation of a porous Si layer in a layer transfer process, Phys. Stat. Sol., (a) 197 (1), pp. 128-131, Apr. 29, 2003, Wiley-VCH Verlag GmbH & Co., KGaA, Weinheim.
Solanki, et al., Development of solar cell processes for free-standing thin silicon films, Physics of Semiconductor Devices, pp. 1145-1147, 2004 Narosa Publishing House, New Delhi, India.
Solanki, et al., Transfer of a thin silicon film on to a ceramic substrate, Thin Solid Films 403-404, pp. 34-38, 2002 Elsevier Science B.V.
Solanki, et al., Free-Standing Thin-Film Monocrystalline Silicon (FMS) Solar Cells, PV in Europe-From PV Technology to Energy Solutions, pp. 387-392, Oct. 7-11, 2002, Rome, Italy.
Interuniversitair Microelektronica Centrum (IMEC)
Knobbe Martens Olson & Bear LLP
Pert Evan
LandOfFree
Method and apparatus for continuous formation and lift-off... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method and apparatus for continuous formation and lift-off..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for continuous formation and lift-off... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3498846