Back-side hydrogenation technique for defect passivation in silicon solar cells

Patent · Tue Apr 19 00:00:00 EDT 1994

OSTI ID:5131536

Sopori, B L

A two-step back-side hydrogenation process includes the steps of first bombarding the back side of the silicon substrate with hydrogen ions with intensities and for a time sufficient to implant enough hydrogen atoms into the silicon substrate to potentially passivate substantially all of the defects and impurities in the silicon substrate, and then illuminating the silicon substrate with electromagnetic radiation to activate the implanted hydrogen, so that it can passivate the defects and impurities in the substrate. The illumination step also annihilates the hydrogen-induced defects. The illumination step is carried out according to a two-stage illumination schedule, the first or low-power stage of which subjects the substrate to electromagnetic radiation that has sufficient intensity to activate the implanted hydrogen, yet not drive the hydrogen from the substrate. The second or high-power illumination stage subjects the substrate to higher intensity electromagnetic radiation, which is sufficient to annihilate the hydrogen-induced defects and sinter/alloy the metal contacts. 3 figures.

• DOE Contract Number: AC02-83CH10093
• Assignee: Midwest Research Inst., Kansas City, MO (United States)
• Patent Number(s): US 5304509; A
• Application Number: PPN: US 7-934025
• OSTI ID: 5131536
• Resource Relation: Patent File Date: 24 Aug 1992
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
36 MATERIALS SCIENCE
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
SILICON
ION IMPLANTATION
SILICON SOLAR CELLS
FABRICATION
CRYSTAL DEFECTS
ELECTROMAGNETIC INTERACTIONS
PHYSICAL RADIATION EFFECTS
REPAIR
BASIC INTERACTIONS
CRYSTAL STRUCTURE
DIRECT ENERGY CONVERTERS
ELEMENTS
EQUIPMENT
INTERACTIONS
PHOTOELECTRIC CELLS
PHOTOVOLTAIC CELLS
RADIATION EFFECTS
SEMIMETALS
SOLAR CELLS
SOLAR EQUIPMENT
140501* - Solar Energy Conversion- Photovoltaic Conversion
360605 - Materials- Radiation Effects
665300 - Interactions Between Beams & Condensed Matter- (1992-)