Infrared Camera-based Imaging Techniques for Solar-grade Silicon

A major challenge for the rapidly growing
photovoltaic market is the reduction of production
costs. Fast and reliable characterisation techniques
for base materials are one possibility. This book is
focused on both developing and investigating the
capabilities of infrared (IR) camera-based
characterisation techniques feasable of measuring the
efficiency limiting parameters of crystalline silicon
solar cell material. Three techniques are
investigated, which measure the IR emission of either
photogenerated or bias-induced free excess carriers
using lock-in thermography. The ILM technique
measures the spatially resolved lifetime of charge
carriers in solar-grade silicon. Based on our
improved setup lifetimes as short as 1µs are
measurable in only 1s. The ITM technique allows the
investigation of spatially distributed
minority-carrier trapping centres in silicon wafers,
whereas the ICM technique measures the spatially
resolved capacitance, which can be used to generate
mappings of the base-doping concentration of solar
cells. This book is addressed to researchers as well
as companies in the field of photovoltaics and other
bussinesses willingly to apply camera-based imaging
techniques.