The diffusion length is referred to the typical distance an unattached electron or hole travels before joining up with another electron or hole. This typical distance a carrier travels, between generation and recombination, is known as the diffusion length. Heavily doped semiconductor materials have faster recombination rates and subsequently shorter diffusion lengths.
Higher diffusion lengths are a crucial factor to take into account with semiconductor materials because they are a sign of materials with extended lifetimes. The average distance a carrier can travel from its site of generation until it recombines is the minority carrier diffusion length, which is the second recombination rate-related parameter.
How is diffusion length affected by collection probability?
The diffusion length and the collection probability are closely linked. The nature and intensity of recombination processes in the semiconductor have a significant impact on the minority carrier’s lifetime. SRH recombination is the predominant recombination process for many varieties of silicon solar cells.
The number of defects in the material will determine the recombination rate, so as doping the semiconductor rises, so will the number of defects in the solar cell. SRH rearrangement will happen more frequently as a result of doping.
Additionally, as doping levels rise, the recombination process itself becomes more effective because Auger recombination occurs more frequently in highly doped and energized materials. It is significantly influenced by the fabrication procedure used to create the semiconductor wafer as well as the processing.
Also Read: What is Diffusion Furnace?
The average distance that an excited carrier will traverse before recombining is known as the diffusion length of a carrier type in a material. It can be calculated with the following formulae:
LD=√DT
where “D†is the diffusion factor and “T†is the excited carrier’s lifespan.
