Dry texturing of solar cells

Patent · Tue Oct 25 00:00:00 EDT 1994

OSTI ID:7193238

Sopori, B L

A textured backside of a semiconductor device for increasing light scattering and absorption in a semiconductor substrate is accomplished by applying infrared radiation to the front side of a semiconductor substrate that has a metal layer deposited on its backside in a time-energy profile that first produces pits in the backside surface and then produces a thin, highly reflective, low resistivity, epitaxial alloy layer over the entire area of the interface between the semiconductor substrate and a metal contact layer. The time-energy profile includes ramping up to a first energy level and holding for a period of time to create the desired pit size and density and then rapidly increasing the energy to a second level in which the entire interface area is melted and alloyed quickly. After holding the second energy level for a sufficient time to develop the thin alloy layer over the entire interface area, the energy is ramped down to allow epitaxial crystal growth in the alloy layer. The result is a textured backside on an optically reflective, low resistivity alloy interface between the semiconductor substrate and the metal electrical contact layer. 9 figs.

• DOE Contract Number: AC02-83CH10093
• Assignee: Midwest Research Inst., Kansas City, MO (United States)
• Patent Number(s): US 5358574; A
• Application Number: PPN: US 8-155385
• OSTI ID: 7193238
• Resource Relation: Patent File Date: 22 Nov 1993
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
REFLECTIVE COATINGS
TEXTURE
SOLAR CELLS
EPITAXY
FABRICATION
LAYERS
OPTIMIZATION
VISIBLE RADIATION
COATINGS
DIRECT ENERGY CONVERTERS
ELECTROMAGNETIC RADIATION
EQUIPMENT
PHOTOELECTRIC CELLS
PHOTOVOLTAIC CELLS
RADIATIONS
SOLAR EQUIPMENT
140501* - Solar Energy Conversion- Photovoltaic Conversion