Method and Apparatus For Reduction of Solar Cell LID

摘要

Reduction of solar wafer LID by exposure to continuous or intermittent High-Intensity full-spectrum Light Radiation, HILR, by an Enhanced Light Source, ELS, producing 3-10 Sols, optionally in the presence of forming gas or/and heating to within the range of from 100° C.-300° C. HILR is provided by ELS modules for stand-alone bulk/continuous processing, or integrated in wafer processing lines in a High-Intensity Light Zone, HILZ, downstream of a wafer firing furnace. A finger drive wafer transport provides continuous shadowless processing speeds of 200-400 inches/minute in the integrated furnace/HILZ. Wafer dwell time in the peak-firing zone is 1-2 seconds. Wafers are immediately cooled from peak firing temperature of 850° C.-1050° C. in a quench zone ahead of the HILZ-ELS modules. Dwell in the HILZ is from about 10 sec to 5 minutes, preferably 10-180 seconds. Intermittent HILR exposure is produced by electronic control, a mask, rotating slotted plate or moving belt.

主权项

1. Apparatus for treating Si wafers for solar cells to reduce the Light Induced Degradation (LID) resulting from in-use operation of said solar cell during exposure to sunlight, comprising in operative combination:
a. means for retaining an Si wafer in a treatment zone in a generally horizontal plane, said Si wafer having a top and a bottom surface oriented with said top surface facing upwardly while being retained in said horizontal plane of said treatment zone; b. at least one Extended Light Source (ELS) outputting high-intensity full-spectrum light radiation (HILR) disposed in said treatment zone above said top surface of said Si wafer to expose said Si wafer top surface to HILR in excess of 3 Sols for a time period sufficient to reduce the LID effect that would otherwise be exhibited by said wafer.